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Getting Started with EnergyPlus

1. JeatherData USA_CA 3 C EnergyPlus E xampleFiles 1ZoneUncontrolled idf C EnergyPlus WeatherD ata USA_FL_Tampa_TMY2 epw 4 C EnergyPlus E xampleFiles 3zvent idf C EnergyPlus WeatherD ata US4 _CA_San Francisco_TMY2 epw 5 C EnergyPlus E xampleFiles 3zvent idf C EnergyPlus WeatherD ata USA4_CO_BoulderTMY2 epw 6 C EnergyPlus ExampleFiles 3zvent idf C EnergyPlus WeatherData USA_FL_Tampa_TMY2 epw 7 C EnergyPlus E xampleFiles 3zvent4utoCalcO hw indPressureCoefts idf C EnergyPlus WeatherData USA_CA_San Francisco_TMY2 epw 8 C EnergyPlus ExampleFiles 3zvent4utoCalcO fwindPressureCoefts idf C EnergyPlus WeatherData USA_CO_BoulderTMY2 epw 9 C EnergyPlus E xampleFiles 3zvent4utoCalcO fw indPressureCoefts idf C EnergyPlus WeatherD ata USA_FL_Tampa_TMY2 epw Add More Simulations Delete Simulation Figure 7 Step 3 of New Group Wizard The next step of the wizard allows you to decide exactly where you want the output files located and what they should be named For most people just trying to group their simulations and wanting the output files in the same directory as the input files just select Original Input File Locations 4 22 05 16 RUNNING ENERGYPLUS EP LAUNCH PROGRAM 4 22 05 w New Group of Simulations i 7 Step 4 of 5 Output File Locations pi the same directory and use the same file name as each original file With this option either the Single Simulation tab or the Histo
2. are messages from the DOE2Translator program that may be helpful in understanding the limits of the translation The D2EP log file contains a detailed log of the translation process The D2E_TEMP txt file contains an intermediate version of the log file Both of these files are created in the same directory as the DOE2Translator program and can usually be deleted Since DOE 2 1e and EnergyPlus share a common macro language many macro features are passed to the EnergyPlus file unchanged including set1 if def and other macro commands References to macro variables i e var and expressions i e x 1 are usually passed through to the resulting EneryPlus IMF unless the DOE2Translator needs to understand that field during the translation process The DOE2Translator does not evaluate macro expressions and if it needs to understand a field value and a macro is present instead will use a default value for the field instead Most fields do not need to be understood by the translator and are directly passed through to the IMF file unchanged Files that are included with the include are not translated automatically and would each need to be run through the DOE2Translator If the included file does not have the INP extension it would need to be changed prior to the translation In addition the user would need to edit the include commands to use the IMF extension instead of the INP extension 43 CREATING INPUT FILES
3. EnergyPlus has its roots in both the BLAST and DOE 2 programs BLAST Building Loads Analysis and System Thermodynamics and DOE 2 were both developed and released in the late 1970s and early 1980s as energy and load simulation tools Their intended audience is a design engineer or architect that wishes to size appropriate HVAC equipment develop retrofit studies for life cycling cost analyses optimize energy performance etc Born out of concerns driven by the energy crisis of the early 1970s and recognition that building energy consumption is a major component of the American energy usage statistics the two programs attempted to solve the same problem from two slightly different perspectives Both programs had their merits and shortcomings their supporters and detractors and solid user bases both nationally and internationally Like its parent programs EnergyPlus is an energy analysis and thermal load simulation program Based on a user s description of a building from the perspective of the building s physical make up associated mechanical systems etc EnergyPlus will calculate the heating and cooling loads necessary to maintain thermal control setpoints conditions throughout an secondary HVAC system and coil loads and the energy consumption of primary plant equipment as well as many other simulation details that are necessary to verify that the simulation is performing as the actual building would Many of the simulation characteristics
4. you can hand edit a file using your knowledge of the IDD comments in the IDF file and a text editor such as NOTEPAD For creating HVAC simulations the HVAC templates are also available IDD Conventions 4 22 05 The following is a basic description of the structure of the IDD it s actually taken directly from the IDD file As noted within signifies a comment character as does the has also been adopted as a convention for including more specific comments about each field in an object These have been used with success in the IDFEditor and it is hoped the flexibility will provide other interface developers with useful information Not all fields are filled in as of yet in the existing IDD that will come over time 36 CREATING INPUT FILES IDD CONVENTIONS 4 22 05 l e Field level comments field note Xrequired field Nun us ip units minimum minimum gt maximum maximum lt default type key key object list xamples reference commented Name of field should be succinct and readable blanks are encouraged Note describing the field and its valid values To flag fields which may not be left blank this comment has no value Units must be from EnergyPlus standard units list EnergyPlus units are s
5. Table 11 Table of Metered Fuel Types Energy Fuel Type Electricity Coal The end use types are shown in the following table Table 12 End Use Category Types End Use Types GeneralLights TaskLights ExteriorLights Heating Cooling DHW Cogeneration ExteriorEquipment ZoneSource PurchasedHotWater PurchasedChilledWater 53 INDEX LIBRARY FILES Index B bugreprt txt 8 Building Simulation 24 Checklist 24 Model Construction 27 Compile Information Building 32 Subsurface 32 Surface 32 Zone 32 Compile Space Gain Data 34 Construction Elements 31 Equivalent Surfaces 30 Surface Types 27 Zone 24 C CSVProc 49 D Data Files 50 E Energy Meters 51 Energy idd 8 EnergyPlus exe 8 EP Launch 9 eplusout bnd 49 EP Macro exe 8 H HVAC Diagram 49 IDFEditor 8 Index 54 Input Files 21 Energy idd 21 Energy ini 21 in epw 21 in idf 21 Input Files Create 36 BLAST Translator 42 Compact HVAC Objects 45 DOEZTranslator 43 EnergyPlus Units 38 GroundTemperatures 45 HVAC Templates 45 IDD Conventions 36 IDFEditor 39 Caveats 42 4 22 05 Change Values 41 Class List Objects 40 Working with 41 Create Select IDF 40 Edit Menu 41 File Menu 41 Help Menu 42 Start 40 View Menu 41 IFCtolDF Utility 44 Library Data Sets 45 Macro Facility 44 Performance Curves 45 Text Editor 44 K Key Features 1 L
6. and other information This changes some of the information that is shown in the Interface Developer s guide The most current information is in the actual Energy idd delivered with the program In addition to the four methods for creating inputs described below several other items are described that may assist you in getting the results you want from EnergyPlus in a timely manner Four methods are available to create input files 1 IDFEditor this is a very simple intelligent editor that reads the IDD and IDFs and allows creation revision of IDF files It can be run from a shortcut in the main EnergyPlus directory created as part of the install or directly from EP Launch 2 BLAST Translator if you already have BLAST and or BLAST input files this program will produce the bulk of a translation to EnergyPlus for you lt generates a complete IDF file but does not include specifics for Systems or Plants It does include the System and Plant schedules that were in the BLAST deck Many of the sample files included with the install started out as BLAST input files 3 DOE 2 Translator if you already have DOE 2 1e input files this program will produce the bulk of a translation to EnergyPlus for you It generates a IMF input macro file that must be run through the EnergyPlus Macro EPMacro program before it can be used by EnergyPlus 4 Hand editing for simple changes to an existing file such as one of the sample files
7. documentation library No program is able to handle every simulation situation However it is the intent of EnergyPlus to handle as many building and HVAC design options either directly or indirectly through links to other programs in order to calculate thermal loads and or energy consumption on for a design day or an extended period of time up to including and beyond a year While the first version of the program contains mainly features that are directly linked to the thermal aspects of buildings future versions of the program will attempt to address other issues that are important to the built environment water electrical systems etc Although it is important to note what EnergyPlus is it is also important to remember what it is not gt EnergyPlus is not a user interface It is intended to be the simulation engine around which a third party interface can be wrapped Inputs and outputs are simple ASCII text that is decipherable but best left to a GUI graphical user interface This approach allows interface designers to do what they do best produce quality tools specifically targeted toward individual markets and concerns The availability of EnergyPlus frees up resources previously devoted to algorithm production and allows them to be redirected interface feature development in order to keep pace with the demands and expectations of building professionals gt EnergyPlus is currently not a life cycle cost analysis tool It produc
8. these selections viewers and text editors again 19 RUNNING ENERGYPLUS RUNEPLUS BATCH FILE RunEPlus batch file It is simple to run EnergyPlus open a DOS or COMMAND box in the EnergyPlus directory and use the RunEPlus bat procedure file The procedure file takes two arguments the input file name containing the building description and the weather file name RunEPlus lt input_file_name gt lt weather_file_name gt Though it s possible to supply arguments to the batch file with embedded blanks it s better practice not to More extensive information about the intricacies of EnergyPlus execution is given in the next two sections of this document As installed the RunEPlus is ready to run the sample files that are included If you wish to create and run other files you may wish to modify the batch file to your own preferences See Error Reference source not found later in this document for parts of the batch file that you will need to modify Running EnergyPlus by Hand 4 22 05 EnergyPlus is compiled as a 32 bit console application on Windows Windows 95 Windows 98 Windows NT Windows 2000 Windows ME operating systems commonly run on the Intel or compatible processing chips aka WinTel machines To run the program bring up the command prompt and cd to the directory containing the executable Assume that the executable is called EnergyPlus exe In the same directory EnergyPlus expects in idf t
9. Air Temperature C Hourly 34 2 LEF FORK Zone Total Latent Gain J Hourly 4 22 05 47 POSTPROCESSING READVARSESO 4 22 05 38 2 LEFT FORK Zone Total Electric Consumption J Hourly 39 2 MIDDLE FORK Mean Air Temperature C Hourly 40 2 MIDDLE FORK Zone Total Latent Gain J Hourly 44 2 MIDDLE FORK Zone Total Electric Consumption J Hourly 45 2 RIGHT FORK Mean Air Temperature C Hourly 46 2 RIGHT FORK Zone Total Latent Gain J Hourly 50 2 RIGHT FORK Zone Total Electric Consumption J Hourly 76 2 PSI FOYER Lights Return Air Heat Gain J Hourly 77 2 PSI FOYER Lights Radiant Heat Gain J Hourly 80 2 PSI FOYER Lights Total Heat Gain J Hourly 81 2 PSI FOYER Lights Electric Consumption J Hourly 82 2 DORM ROOMS AND COMMON AREAS Lights Return Air Heat Gain J Hourly 83 2 DORM ROOMS AND COMMON AREAS Lights Radiant Heat Gain J Hourly 86 2 DORM ROOMS AND COMMON AREAS Lights Total Heat Gain J Hourly 87 2 DORM ROOMS AND COMMON AREAS Lights Electric Consumption J Hourly 88 2 LEFT FORK Lights Return Air Heat Gain J Hourly 89 2 LEFT FORK Lights Radiant Heat Gain J Hourly 92 2 LEFT FORK Lights Total Heat Gain J Hourly 93 2 LEFT FORK Lights Electric Consumption J Hou
10. BLAST Input File usually called lt something gt bin For anyone that is unfamiliar BLAST stands for the Building Loads Analysis and Systems Thermodynamics computer program A special batch file RunXLate bat can be used to run the translation program Similar to running EnergyPlus see above you run this batch file RunXLate lt blastinputfile gt Where lt blastinputfile gt is the part of the file name without extension The program produces a idf file of the same name The BLASTTranslator uses an Energy ini file for some parameters For example program dir ver surf group weather dir The above BLASTTranslator ini file sets the version of EnergyPlus to the current version and has the surf parameter set to group This BLASTTranslator run will produce an 42 CREATING INPUT FILES DOE2TRANSLATOR EnergyPlus input file for the current release version format and will name surfaces by Zone and Class e g Z2N001 Wall001 The alternative Consecutive will number surfaces in sequence DOE2Translator 4 22 05 The DOE2Translator program creates an EnergyPlus input file from a DOE 2 1E input file The translation is not intended to be complete but simply an aid to help you move your library of DOE 2 1E input files into EnergyPlus You should look over the resulting EnergyPlus input file review the documentation of EnergyPlus and make any necessary edits to the translated fi
11. Figure 8 Simplifications Using Equivalent Surfaces ccceeee 31 Table 4 Building Elements vsircasiindia in 32 Figure 9 Schematic of One Zone Model with Surface Information 33 Table 5 Compilation of Surface Information for the One Zone Model 34 Step 4 Compile Internal Space Gain Data cccccccnnnnooocccccnnnoniccnanannnnnos 34 Table 6 Internal Gain Data sessions 35 Creating Input Files nr ed 36 IDD GONVENONS e dranie Seneca cate a E E a 36 Standard EnergyPlus Units essa ito alla 38 Table 7 Standard EnergyPlus Units ooooocccconnoccccnnnoncccnonannnncncnnanncnnnnns 38 DEE aia R S 39 Figure 10 IDF Editor Screen isis dere nilis 40 Start IDF ECO peene ae eaaa AE cacas ed 40 Creating or Selecting an Input Data File ooon occccnnnnnicccnnacccccccnocaccccnanonos 40 Glass List and ODO cis ieee Cob sect a aeae et aarian 40 Changing Values iia 41 Working with Objects coupe a hela eee 41 File MENU asarre k lso tocan 41 o A a hate et eee 41 4 22 05 TABLE OF CONTENTS MEW MEN il dd 41 Help MU ii a 42 GAN CALS aa 42 PUGS se la O O 42 BLAST Trans ri E E E R ER 42 DOE TANSIAUGE rse e dr iS 43 O A a E E 44 Text EMO cra KEEA A NENAU AAEE EKRE DREAS aa 44 EPM ena E 44 HVAC Templado cs beqcatdened exsutenetenentacdetecadacdtcas sores 45 Compact HVAC Ob 6CIS iii asd tania hi Mean eae 45 Data Sci dais 45 Slab and Basement Prograims oooocccccnononcccnonancncnonannnnnnnnnnnnnnnncnnnnnnannnnnnnnnnnnnns
12. If DEBUG OUTPUT 0 is entered you will get an empty eplusout dbg file eplusout dxf This is a file in AutoCad DXF format showing all the surfaces defined in the IDF file It provides a means of viewing the building geometry The DXF file from EnergyPlus highlights different building elements shading walls subsurfaces in differing colors A number of programs can read and display DXF files One that works well is Volo View Express available free from the Autodesk web site Output of this file is triggered by Report Surfaces DXF in the IDF eplusout sin A text file containing the coordinates of the vertices of the surfaces in the IDF Output of this file is triggered by Report Surfaces Lines in the IDF Postprocessing Program Files A postprocessing program ReadVarsESO exe is available that will read an ESO or MTR file and produce a file that can be read by Excel M It can use an input file or not In batch mode it is run by the little batch file RunReadESO bat Further information on this program is provided later in this document see PostProcessing and in the Input Output Reference as well as the Output Details and Examples documents 4 22 05 23 INFORMATION NECESSARY TO RUN ENERGYPLUS BUILDING SIMULATION Information necessary to Run EnergyPlus Building Simulation If you are already familiar with modeling buildings particularly modeling buildings for energy consumption you may wish to skip to Crea
13. Library Files 50 M Meter End Use Categories 53 Fuel Types 53 Types 52 O Output Files 21 eplusout audit 22 eplusout dbg 23 eplusout dxf 23 eplusout eio 22 eplusout err 21 eplusout eso 22 eplusout rdd 23 eplusout sin 23 P Post Processing 47 Post Processing Programs CSVProc 49 HVAC Diagram 49 ReadVarsESO 47 Postprocessor Files 23 rvi 48 eplusout csv 48 eplusout eso 47 eplusout inp 47 R readme file s 8 ReadVarsESO 47 54 INDEX LIBRARY FILES RunEPlus 9 20 RunEPlus bat 8 W Weather Data 46 4 22 05 2
14. and Spreadsheets in the View Results area of the screen By pressing the Text Output Files button a text editor will open each of the text output files Up to 23 files will open if they exist Selecting Single File from the View menu displays a menu of all available output files from which any file can be opened individually Each file may also be opened with an associated function key The output files and function key shortcuts are listed below 1 Main Results File tabulated results in comma tab or space delimited format generated by the ReadVarsESO postprocessor F4 ESO raw report variable output F5 RDD list of output variables available from the run F6 ElO additional EnergyPlus results F7 ERR list of errors and warnings F8 BND HVAC system node and component connection details F9 MTR raw report meter output F11 MTD list of meter component variables F12 METER File tabulated meter report in comma tab or space delimited format generated by the ReadVarsESO posiprocessor Ctrl F4 10 ZSZ zone sizing details in comma tab or space delimited format Ctrl F5 11 SSZ system sizing details in comma tab or space delimited format Ctrl F6 12 AUDIT input file echo with input processor errors and warnings Ctrl F8 13 SLN output from report surfaces lines Ctrl F9 14 DBG output from the debug command Ctrl F1 1 15 CIF COMIS input fil
15. and input files simply push the Simulate button to start the EnergyPlus building energy simulation engine At this point a black DOS window should pop up on your screen and show the progress of your simulation The simulation is complete when the black DOS box closes The EnergyPlus program black DOS window will show scrolling text as the simulation procedure progresses If you would like to see these messages more slowly you have two options 1 Press the Control S key combination to try to stop the progress and any key to continue 4 22 05 10 RUNNING ENERGYPLUS EP LAUNCH PROGRAM 2 Under the View menu on the EP Launch program select Pause During Simulation and this will insert a pre programmed pause immediately after EnergyPlus executes To continue after the pause press any key Looking at the Results After you have run a simulation and the black DOS window closes EnergyPlus has completed and a status message is displayed Figure 2 EnergyPlus Run Status AN EnerayPlus Completed Successfully 7 Warning 1 Severe Errors Figure 4 EP Launch Finish Status After pressing OK from this box selecting ERR ElO BND Output Files Only from the View menu will display the ERR EIO and BND files useful when errors may have occurred Alternatively pressing the F2 function key will display the same three files You can view the results using one of the three buttons Text Output Files Drawing File
16. be a black box that is unintelligible to the users and developers around the world While there are many conflicting ideas on what is meant by open EnergyPlus is certainly not closed since this would be counter to the goals that have already been stated The hope is that this access to source code will improve the accuracy and usability of the program over the long term and allow many developers to work on the program simultaneously This developer friendly stance is critical to keeping EnergyPlus current and in step with technological advances In summary the goals of EnergyPlus are ambitious but achievable via the path described above EnergyPlus aims to be a program that is relatively simple to work with from the perspective of both the users and the developer The development team made tremendous efforts to keep simulation code and algorithms as separate as possible and as modular as possible to minimize the overall knowledge that someone would need to have to add models to the program This will minimize the resource investment and maximize the impact of current research in the field of building energy analysis and thermal load calculations Finally the full coupling of building envelopes systems and plants will provide a better understanding of how a building responds not only to the environmental factors that impact the building but also the HVAC system as it attempts to meet the thermal loads on the building It is also important
17. have been inherited from the legacy programs of BLAST and DOE 2 Below is list of some of the features of the first release of EnergyPlus While this list is not exhaustive it is intended to give the reader and idea of the rigor and applicability of EnergyPlus to various simulation situations gt Integrated simultaneous solution where the building response and the primary and secondary systems are tightly coupled iteration performed when necessary gt Sub hourly user definable time steps for the interaction between the thermal zones and the environment variable time steps for interactions between the thermal zones and the HVAC systems automatically varied to ensure solution stability gt ASCII text based weather input and output files that include hourly or sub hourly environmental conditions IFC driven object definitions and standard and user definable reports respectively gt Heat balance based solution technique for building thermal loads that allows for simultaneous calculation of radiant and convective effects at both in the interior and exterior surface during each time step gt Transient heat conduction through building elements such as walls roofs floors etc using conduction transfer functions gt Improved ground heat transfer modeling through links to three dimensional finite difference ground models and simplified analytical techniques gt Combined heat and mass transfer model that accounts for moisture adsorp
18. structured from a module tree inverted tree perspective One of the most important features of this document is a list of standard EnergyPlus service subroutines and modules that greatly simplify the developers task of integrating their work into the program Input and output issues are also addressed from the perspective of how modules actually obtain data from the input file and how each section of the code sends data to the output files The appendices of this document list code for two global data modules that are available to all parts of the code through the FORTRAN9O USE statement FAQ Document The Frequently Asked Question Commonly Asked Questions document contains questions and answers about EnergyPlus 4 22 05 7 GETTING STARTED WITH ENERGYPLUS FAQ DOCUMENT Getting Started with EnergyPlus The standard install procedure has put the following information on your computer in the directories shown You were allowed to select components so all of these may not be there EnergyPlus the main execution area contains Energy idd EnergyPlus exe RunEPlus bat shortcut to IDFEditor readme file s EP Macro exe bugreprt txt file This will also contain the translation exe for converting last release input files to the current release see Auxiliary Programs document for details and the WinEPDraw program again in Other Information document If chosen the EP Launch program will be in this directory as wel
19. surfaces and on the zone air For purposes of the heat transfer calculations a geometrically correct rendering of the zone surfaces is not required The surfaces do not even have to be connected As long as the program knows to which thermal zone mass of air each surface transfers heat it will calculate all heat balances correctly For example all heat storage surfaces of the same construction within a zone may be defined as a single rectangular surface The size of this equivalent surface will equal the sum of all the areas of all the heat storage surfaces in the zone A few simple rules will further explain what we mean by equivalent surfaces and how these surfaces may be used Remember that these are guidelines for optional simplification of input Each simplification must be evaluated to determine if it would significantly impact certain shading interior solar gains or daylighting features The goal is to seek an adequate level of detail to capture the key features of the building envelope without spending excess time describing and computing results for details that are insignificant 1 Define all roofs and floors as rectangles regardless of the shape of the zone Each zone may have one rectangular roof and one rectangular floor of a given construction 2 Define all heat storage surfaces of the same construction within a zone as a single surface The size of the single surface is obtained by summing the individual surface areas exposed to
20. to note that testing and verification are key issues in the development of any new program such as EnergyPlus While there are large sections of EnergyPlus that consist of brand new code the majority of the heat balance code can be traced back to the original parent programs It should be noted that while this code has been significantly reengineered the team used what has been termed an evolutionary reengineering ER process In ER program code is modified stepwise in an effort to restructure it modularize it replace old obsolete data structures etc The ultimate goal is to bring it up to current programming standards without starting over with new code At each step along the way the program is exercised over a variety of input files and parameters to insure that what were intended to be algorithm neutral changes in the program have not resulted in changes to the 5 ENERGYPLUS OVERVIEW ENERGYPLUS DOCUMENTATION LIBRARY output This process was very successful and bolstered confidence in the program In addition comparisons could be made back to legacy programs to show that the new program is at a minimum as accurate as its predecessors Beyond this EnergyPlus has also been subjected to a lengthy and rigorous testing plan by an outside agency as well as numerous beta testers This level of effort and collaboration is unprecedented in the history of energy analysis and thermal load calculation programs and has resulted in a much higher
21. 3 exterorwal const te 5535353 4 window ow S e 5 exterorwal const ns 3 6 www aw 7 exeriorwal consi 4333 window aw m lg exteriorwal consi 34 J 53535353 10 window aow e 11 exteriorwal const 6 12 window dpw tt 13 exterorwai consi 39 fJ i window ow we 15 extriorwall cons 6 6 wnow ow tc 17 exterorwall consti 2 window aw ana a A o exteriorwal const 20 2an waw ow Tt le exterorwall consu 733 23 window aow 24 exterior wall const _ ___ 25 window Epa eae 27 window aw ae roo coss texte 13450 29 tor conse wexw6 13450 30 inemalmass conste 1030 31 intemalmass consg__ 1890 Table 5 Compilation of Surface Information for the One Zone Model The column headings in the previous table have the following meanings Type A shortened notation for the surface type in EnergyPlus to differentiate between heat storage surfaces and various types of heat transfer surfaces Construction A name for the surface construction types Length The length of base surfaces An equivalent size of roofs and floors is also included Area The area of subsurfaces Step 4 Compile Internal Space Gain Data People lights equipment outside air infiltration and ventilation all constitute interna
22. 45 Coefficient Curve GeneratiON oooococconnnccccnnononcccncnannnnnnnonnnnnnnnnnnnnnnnnnnnnnnnnannnns 45 o O cans ce eetasetnestaretersanretnenearesend 46 Table 8 Formats of weather data on the web Site eee 46 Table 9 General Locations of Weather Sites on web pag 05 46 POSTAS AA 47 Res NAET SO st usais 47 PostProcessing Files details conocio 47 BPIUISOUE AP tn lt 47 A A A RS OENES HESA 47 OPIUSDULES Vida 48 AVAG Dia gra Maai oda 49 O 49 PVCU IOS ti NAO 50 4 22 05 TABLE OF CONTENTS A O Gat Wedesntacle 50 Energy Mi Ed 51 Figure 11 Illustration for Energy Meters oooooocccccccccononononcccncnnnononnnnnnnnnnos 51 Table 10 Overall Meter Typ8sS cooooocccncnncccccncnocccccnnnancccnnannnnnnnrannnnnnnnnns 52 Table 11 Table of Metered Fuel Types ccoooocoonicccccccccncnnnnnanccnnnnnnnnnn 53 Table 12 End Use Category Types cccooooccccnnnoncccnonancncncnnancnnnonanananannnns 53 NR 54 4 22 05 ENERGYPLUS OVERVIEW WHAT IS ENERGYPLUS EnergyPlus Overview Welcome to EnergyPlus This section offers a big picture view of what EnergyPlus is what it does why it exists and what its goals are AND provides an overview to the EnergyPlus documentation library While this document does not provide every detail on the program it does give the reader a macroscopic view of EnergyPlus and how it is intended to fit into the energy analysis and thermal load simulation software continuum What is EnergyPlus
23. ALS 4 22 05 difficult to maintain support and enhance Neither BLAST nor DOE 2 is able to correctly handle feedback from the HVAC system to the zone conditions Finally the speed with which new technology in the HVAC field is developed has far outpaced the ability of the support and development groups of both programs to keep the programs current and viable This is really the key issue in the existence of EnergyPlus there simply are not enough researchers worldwide who have enough experience with the complex code of the programs to keep pace with new technology In addition due to the years of experience necessary to make modifications to either BLAST or DOE 2 it is extremely expensive and time consuming to produce models or train someone to become proficient in either program s code The following paragraphs address how the goals of EnergyPlus have been carefully selected to solve the problems of the legacy programs and to make EnergyPlus an international repository for algorithms that can be made available to all interested parties Structure and Simulation Management The spaghetti code nature of the parent programs resulted in great confusion as to how information flowed within the program when data was modified or should be modified and what was happening when Thus one of the goals of EnergyPlus development was to eliminate the interconnections between various program sections and the need to understand all parts of the c
24. CO_Boulder_TMY2 epw 52one irCooled_1 2004 4u9 02 14 21 31 5Zone irCooled idf USA_CO_Boulder_TMY2 epw 52one irCooled_1 2004 4ug 02 14 21 49 52ZoneAirCooled idf US4_CO_Boulder_TMY2 epw 5ZoneAirCooled_1 2004 Aug 02 14 22 08 52ZoneAirCooled idf US4_CO Boulder TMY2 epw 5ZoneAirCooled_1 2004 4ug 02 14 22 26 52ZoneAirCooled idf US4_CO_Boulder_TMY2 epw 52one irCooled_1 2004 4ug 02 14 22 38 52ZoneAuto idf A52one uto_1 2004 4ug 02 15 38 38 LoD fA idf USA_IL_Chicago OHare_TMY2 epw LgOf Ay View File EnerayPlus 1 2 0 021 Exit H A 4 Figure 9 History Tab You can expand the level of detail by clicking on the plus signs or double clicking on the entry The detail shown includes the names of all the input and output files associated with that simulation along with the message summary of the warnings and errors generated It is possible that a file may be shown that no longer exists The View Files button will display the selected file using a spreadsheet text editor DXF file viewer SVG file viewer or HTML web browser When groups of simulations are performed using the Group of Simulations tab and User Defined Locations are used for the output files the history view is the only way to access those files using EP Launch The history tab displays the HISTORY CSV file that is located in the same directory as EP La
25. ENERGYPLUS Getting Started with EnergyPlus Everything You Need to Know about Running EnergyPlus anda startat building simulation Date April 21 2005 COPYRIGHT 1996 2005 THE BOARD OF TRUSTEES OF THE UNIVERSITY OF ILLINOIS AND THE REGENTS OF THE UNIVERSITY OF CALIFORNIA THROUGH THE ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY ALL RIGHTS RESERVED NO PART OF THIS MATERIAL MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM OR BY ANY MEANS WITHOUT THE PRIOR WRITTEN PERMISSION OF THE UNIVERSITY OF ILLINOIS OR THE ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY ENERGYPLUS IS A TRADEMARK OF THE US DEPARTMENT OF ENERGY TABLE OF CONTENTS ENGI IUS OVAS 1 Whatis En roy Plus cuicos dial 1 Why does EnergyPlus exist and what were its original goals 2 Figure 1 EnergyPlus the big picture cccccecesseeeeeceeeeeseeeeeeeseeeeeee 4 Figure 2 EnergyPlus Internal elements 5 EnergyPlus Documentation Library ccccccsessesecccceeeeeeeeeeeeeeeeeeneeeeeeeeesees 6 User Information DOCUMENTS ecccceeeeeeeeeeeeeeeeeeeeeeeeseneeeeeeeeneneeeeneesees 6 Engineering Reference DoCUMent ccccceseeeeeeeeeceeeeeeeeeeeeeneeeeeeeeeeenenseees 6 Developer Information DOCUMENTS oooooccccccccnonanaconanancnccnnonnnnnonannrnnnnn nn nc nano 7 FAQ DOCUS Ea acordate 7 Getting Started with EnergyPIus cccescesceeseeeeeeseeeeeeeeeseeeaeeeeeeaeeeaeeenea
26. ENERGYPLUS ENERGYPLUS FILES EnergyPlus Files 4 22 05 Input Files The following files are input to the EnergyPlus program Energy idd The input data dictionary IDD is an ascii text file containing a list of all possible EnergyPlus objects and a specification of the data each object requires This file is analogous to the DOE 2 keyword file The Guide for Interface Developers contains a full description of the input data dictionary in idf The input data file IDF is an ascii file containing the data describing the building and HVAC system to be simulated The Guide for Interface Developers shows examples of IDF input Many example files are installed as part of the EnergyPlus installation Energy ini This is the EnergyPlus initialization file It is an optional ascii input file that allows the user to specify the path for the directory containing Energy idd This file using the actual directories of the install will be created during the install An example is program dir C EnergyPlus weather dir spark dir C EnergyPlus sparklink packages The weather portion of the initialization file is unused The spark item points to the root folder for SPARK packages in epw The EnergyPlus weather file is an ascii file containing the hourly or sub hourly weather data needed by the simulation program The data format is described in the Guide for Interface Developers and the Other Informat
27. Electricity J Zone Meter GeneralLights Electricity Zone RESISTIVE ZONE J Zone Meter GeneralLights Electricity Zone EAST ZONE J Zone Meter GeneralLights Electricity Zone NORTH ZONE J 4 22 05 The VarType Zone field designates that each meter will be available at the Zone Time Step resolution that is whatever is specified by the TimeSteps in Hour user input The Var Report Type Meter field shows that these are meters 51 ENERGY METERS LIBRARY FILES The Variable Name really the Meter Name shows the name as well as the units for reporting Units illustrate the units for these meters We are currently allowing two possibilities for water units both m for water that is consumed on the property as well as joules for water that might be purchased for energy use or other hot cold energy water usage Table 10 Overall Meter Types Meters Facility Building You can report on meters at the zone time step but you can also have the reporting at other frequencies e g hourly daily monthly overall simulation For the more general resolutions the values of the meter are shown along with minimum and maximum values For example 26 Electricity Facility J RunPeriod 301 Electricity Building J RunPeriod 306 Electricity Zone RESISTIVE ZONE J RunPeriod 311 Electricity Zone EAST ZONE J RunPeriod 316 Electricity Zone NORTH ZONE J RunPeriod 42 ExteriorEquipment Gas J RunP
28. IFCTOIDF In this version of the DOE2Translator program translation is limited to the following DOE 2 commands which represent the majority of the building envelope and internal gains SPACE except SHAPE BOX SPACE CONDITIONS DAY SCHEDULE except use of HOURS and VALUES keywords WEEK SCHEDULE except use of DAYS and DAY SCHEDULE keywords SCHEDULE except use of WEEK SCHEDULE keyword ATERIAL LAYERS CONSTRUCTION EXTERIOR WALL ROOF except polygon INTERIOR WALL FIXED SHADE WINDOW DOOR RUN PERIOD DESIGN DAY LIKE SET DEFAULT IF CtolDF The IFCtolDF utility extracts the geometric representation of building space and envelope surface and opening object instances contained within an Industry Foundation Classes IFC data file then creates an EnergyPlus Input Data File IDF containing these objects mapped to the EnergyPlus Input Data Dictionary IDD The IFCtoIDF utility deals only with the geometry of building spaces and surfaces without addressing the material characteristics of these building elements lt is anticipated that this utility will be enhanced over time to extract and map other information contained in an IFC data file that is relevant to performing an EnergyPlus simulation The utility has been developed as a Window dynamic link library DLL that reads an IFC data f
29. Update Modules Feedback 3 Calculation Results Figure 1 EnergyPlus the big picture Integration of Loads Systems and Plants One of the strong points of EnergyPlus is the integration of all aspects of the simulation loads systems and plants Based on a research version of the BLAST program called IBLAST system and plant output is allowed to directly impact the building thermal response rather than calculating all loads 4 ENERGYPLUS OVERVIEW WHY DOES ENERGYPLUS EXIST AND WHAT WERE ITS ORIGINAL GOALS first then simulating systems and plants The simulation is coupled allowing the designer to more accurately investigate the effect of undersizing fans and equipment and what impact that might have on the thermal comfort of occupants within the building The diagram below shows a basic overview of the integration of these important elements of a building energy simulation Sky Model EnergyPlus Air Loop Simulation Manager 9 Module Daylighting 1 Module Plant Loop Module Window Glass A Nw Condenser Module j ac my Loop Module CTF L Calculation COMIS PV Module Module 4 22 05 Module Shading T Zone Equip Module gt Yr Module Figure 2 EnergyPlus Internal elements Open Source Code Another advantage of EnergyPlus that it shares with both BLAST and DOE 2 is that the source code of the program will be available and open for public inspection revision etc The program is not intended to
30. Viewer then locating the executable file for your favorite drawing software capable of reading a DXF file AutoDesk s VoloView Express may be used as the DXF file viewer It is available for free from AutoDesk s web site A viewer for HVAC diagrams created by EnergyPlus using the SVG file extension may also be selected from the file menu Some output reports may be put into HTML format A viewer for these files a standard Internet web browser may also be selected from the file menu The selection of viewers is saved between times that you use the EP Launch application If one of the file types TXT CSV or DXF does not have an associated application you will be prompted to select a program exe when you try to view or edit that file type To reset the default applications select Autofind Programs from the File menu RUNNING ENERGYPLUS EP LAUNCH PROGRAM File Menu The File menu can be used for selecting input and weather files just like the Browse buttons see the Selecting Input and Weather Files section above In addition the File menu is used to select the appropriate file viewers editors see the Selecting Viewers and Editor section above and can be used to run a simulation Edit Menu No cutting or pasting is used in this program so the edit menu shows options that duplicate the functions of the Edit Text Editor and Edit IDF Editor buttons In addition the weather file and the postprocessor command file r
31. ace of a wall Consider the single zone model The following figure is a schematic representation of a one zone representation The figure shows the location of the zone origin the length of all 32 INFORMATION NECESSARY TO RUN ENERGYPLUS A METHODOLOGY FOR USING ENERGYPLUS base surfaces and the areas of all subsurfaces windows and doors The surfaces are numbered counter clockwise around the zone beginning at the zone origin as shown the table below the table of required zone information compiled by the user A few simple conventions should be followed to facilitate the construction of zone information tables 1 Number all surfaces in order counter clockwise around the zone 2 Keep the subsurfaces with the base surface on which they are located 3 Specify lengths for base surfaces and areas for subsurfaces and internal mass 4 Specify the roof and floor as rectangles of the correct size 0 Buildi m North Axis cds a 180 Surface Facing Angles 50 39 84 12 62 12 8l a H a Gl a D ii a IS E oe Bor o j p P a a 3 8 a Wt 34 t m o H 20 o 26 t2 82 2 40 2 Ja uw Si Fe Zone 363 12 ngm p Fr 113 t S a y 61 t2 q a 501 Figure 9 Schematic of One Zone Model with Surface Information Zone 1 length lv exteriorwall cons so 4 22 05 33 INFORMATION NECESSARY TO RUN ENERGYPLUS A METHODOLOGY FOR USING ENERGYPLUS window pw S e
32. allows the building geometry to be viewed without running a full simulation For more information about WinEPDraw see the Auxiliary EnergyPlus Programs document Editing the Input Files The input file called IDF file that is selected from the top pull down list can be edited by pressing one of two buttons in the Input File area The Edit Text Editor button will start a text editor and the Edit IDF Editor will start the separate program called the IDF Editor Remember to save any changes you make in either editor before returning to EP Launch to run the simulations again Selecting Viewers and Editors The default text editor that the EP Launch program will start is the application associated with txt files usually NOTEPAD EXE This can be changed to your favorite text editor by going to the File menu in EP Launch and clicking on Select Text Editor then locating the executable file for your favorite editor The default spreadsheet program is the application associated with CSV files such as Microsoft Excel This can be changed to your favorite spreadsheet program by going to the File menu in EP Launch and clicking on Select Spreadsheet Program then locating the executable file for your favorite spreadsheet software The default drawing viewer is the application associated with DXF files This can be changed to your favorite spreadsheet program by going to the File menu in EP Launch and clicking on Select Drawing
33. andard SI units for input and output ASCII with no spaces is used for abbreviations Note that exponents appear without any indication of exponentiation i e kg m3 not kg m 3 or kg m 3 Also note the use of dashes We have W m2 K not W m2 K or W m2 k At the end we note the problem variables the inputs that have non standard units Inputs using these units will have to be changed and the code checked to see how the quantities are used internally Table 7 Standard EnergyPlus Units Quantity angular degrees degree Length meter Area square meter Volume cubic meter Time seconds frequency Hertz temperature Celsius absolute temperature Kelvin temperature difference Kelvin Speed meters per second energy or work Joules MI 8B CREATING INPUT FILES IDFEDITOR Power Mass Force mass flow volume flow Pressure pressure difference specific enthalpy Density heat flux specific heat conductivity Diffusivity heat transfer coefficient R value heating or cooling capacity electric potential electric current illuminace luminous flux luminous intensity luminance vapor diffusivity Viscosity Porosity thermal gradient coeff for moisture capacity isothermal moisture capacity IDFEditor Watts kilograms Newton kilograms per second cubic meters per second Pascals Pascals Joules per kilogram kilograms per cubic meter watts per square meter Amperes lux lumen candelas candelas per square mete
34. ax errors in either file Note that both eplusout err and eplusout audit will show the error messages caused by input syntax errors however only ep usout err will show errors issued during the actual simulation eplusout audit can be used when you need to see the context of the error message to fully ascertain the cause eplusout eso The EnergyPlus Standard Output ESO is a text file containing the time varying simulation output The format of the file is discussed in the Guide for Interface Developers and the InputOutputReference The contents of the file are controlled by Report Variable commands in the IDF file Although the ESO is a text file it is not easily interpretable by a human Usually postprocessing will be done on this file in order to put it in a format that can be read by a spreadsheet however a quick visual inspection of the file does show whether the expected variables are output at the desired time step eplusout mtr The EnergyPlus Meter Output MTR is a text file containing the time varying simulation output The format of the file is similar to the ESO file As described in a later section of this document see Energy Meters meters are a powerful reporting tool in EnergyPlus Values are grouped onto logical meters and can be viewed the same way that the ESO variables are used The contents of the file are controlled by Report Meter commands in the IDF file Although the MTR is a text file it is not easily interpretable
35. because the designer expected higher solar loads on the South and West sides of the wing and wanted to examine the distribution as well as the magnitude of the load in the space Zoning concept number 2 above leads to an important final point concerning the zoning of a building for a simulation Complete estimates of the total building load magnitude only may be obtained with very simple models For example the total building load calculated using a one zone model of the Ft Monmouth Education Center Figure below will NOT be significantly different from the total building load calculated using a more detailed model The distribution of the load within the building cannot be estimated with the simplified building model but its magnitude such as would be used in sizing the central plant equipment can be quickly estimated using a very simple model 26 INFORMATION NECESSARY TO RUN ENERGYPLUS A METHODOLOGY FOR USING ENERGYPLUS 4 22 05 Figure 7 Single Zone Model of the Ft Monmouth Education Center Step 3 Prepare to Construct the Building Model Working from blueprints or sketches and following the guidelines in Step 2 the building zones were determined It is recommended that the engineer sketch the building with its zones Surface dimensions should be included in the sketch Additional geometric and surface information is required before an input file describing the building can be constructed Specifically
36. by a human Usually postprocessing will be done on this file in order to put it in a format that can be read by a spreadsheet however a quick visual inspection of the file does show whether the expected variables are output at the desired time step eplusout eio The EnergyPlus Invariant Output ElO is a text file containing output that does not vary with time For instance location information latitude longitude time zone altitude appears on this file 22 RUNNING ENERGYPLUS ENERGYPLUS FILES eplusout rdd The Report variable Data Dictionary RDD is a text file listing those variables available for reporting on the ESO or MTR for this particular simulation Which variables are available for output on the ESO or MTR depends on the actual simulation problem described in the IDF A simulation with no chiller would not permit the output of any chiller report variables The user may need to examine the RDD to find out which report variables are available in a particular simulation The RDD is written only if Report Variable Dictionary appears in the input IDF file eplusout dbg This is a text file containing debug output for use by EnergyPlus developers Generally developers will add debug print statements wherever in the code that that they wish There is a standard debug output that prints out conditions at all the HVAC nodes This output is triggered by placing DEBUG OUTPUT 1 in the IDF file
37. corded for the reporting period along with the timestamp information in the following 4 fields 7 21 1 01 10 July 21 hour 1 and 1 10 minute period in the hour when the minimum occurred Then follows the maximum value for this meter 1 0543500E 08 along with its timestamp information 7 21 18 51 60 July 21 18 hour minutes 51 60 Facility meters contain all the energy of a fuel type Building meters contain the sum of each zone s energy System meters contain the energy from the system components Plant meters contain the energy from the plant equipments Thus the following relationships should be observed Facility gt Building System Plant Exterior 4 22 05 52 ENERGY METERS LIBRARY FILES 4 22 05 NumberOfZones Building gt Zone 1 Meter names are of two forms lt FuelType gt lt name gt or lt EndUseType gt lt FuelType gt lt name gt The user requests reporting by either specifying the full name above without Units or a wildcard represntation of that name to obtain all meters of a type For example entering Electricity for the meter name will report on all the Electricity meters Electricity Facility Electricity Building Electricity Zone Resistive Zone Electricity Zone East Zone Electricity North Zone in the example above Both the fuel types and enduse types are set within the program by the developers Current Fuel types are shown in the table below
38. cture improvements in EnergyPlus solve the problems of not having enough experts to keep up with technology and the large start up time and expense previously needed to bring someone up to speed on program additions Established Links The modularity of EnergyPlus makes it easier for other developers to quickly add other component simulation modules This means that it will be significantly easier to establish links to other programming elements Since initially the EnergyPlus code will contain a significant number of existing modules there will be many places within the HVAC code where natural links to new programming elements can be established These are fully documented to assist other developers in a swift integration of their research into EnergyPlus In addition to these more natural links in the HVAC section of the code EnergyPlus will also have other more fluid links in areas such as the heat balance that will allow for interaction where the modules might be more complex or less component based Again the goal of this feature of EnergyPlus is maximize the number of developers who can quickly integrate their work into EnergyPlus for the minimum investment of resources The following diagram depicts how other programs have already been linked to EnergyPlus and a big picture view of how future work can impact the program Building Description Heat and ES Balance Simulation Building Systems TRNSYS Simulation Pollution Future
39. d prior to an actual simulation The programs are described in the Auxiliary Programs document Coefficient Curve Generation The CoeffConv and CoeffConv utility programs can be used to convert DOE 2 temperature dependent curves Fahrenheit to EnergyPlus temperature curves Centigrade Celsius These programs are described in the Auxiliary Programs document 4 22 05 45 WEATHERDATA COEFFICIENT CURVE GENERATION WeatherData 4 22 05 As mentioned in the Running EnergyPlus section EnergyPlus uses the new E E weather data The new E E format is very flexible as well as being ASCII and somewhat readable In addition to the usual weather data temperatures solar radiation data the format embodies other information from the location and weather data e g design conditions calculated ground temperatures typical and extreme weather periods The EPW weather data format is described in the Input Output Reference Document and Auxiliary Programs Document Other details including statistical reports backgrounds on data sources and formats use of the Weather Converter program used both for processing data and reporting are also provided in the Auxiliary Programs document The web site for EnergyPlus http www energyplus gov provides downloadable weather data for many sites throughout the world from several different formats In addition we are amenable to posting more weather data from users In summary the web site con
40. ditioned by the system Five systems were designed to serve the Ft Monmouth Education Center These systems with the thermal zones they serve are shown in the table below The location of each zone is shown in accompanying figure System System Name CFM Zone Served Number Four Pipe Fan Coil 3900 Zone 1 Four Pipe Fan Coil Zone 2 Single Zone Draw Through Zone 3 Single Zone Draw Through Zone 5 Single Zone Draw Through Zone 6 Unit Heater Zone 4 Unit Heater Zone 7 25 INFORMATION NECESSARY TO RUN ENERGYPLUS A METHODOLOGY FOR USING ENERGYPLUS 4 22 05 Table 2 Zoning the Building by System Type Figure 6 Thermal Zones in the Education Center Notice Zone 1 Zone 2 Zone 4 and Zone 7 The two important zoning concepts can be demonstrated with the zoning of the Ft Monmouth Education Center to reinforce the idea of a thermal zone and encourage the use of simplified models 1 Notice that Zones 4 and 7 include two rooms that are not adjacent to one another but are served by the same system Because the air temperature in the two spaces is maintained at the same uniform temperature the two spaces though separated spatially may be defined as a single zone For our purposes we will define them as separate zones 2 Notice that Zone 1 and Zone 2 are served by the same fan system and could be defined as a single zone with 7650 cfm of conditioned air supplied to the space The space was split into two zones
41. e Ctrl F12 16 SVG HVAC Diagram Shift F4 17 EPMIDF clean idf file after EP Macro processing Shift F5 18 EPMDET EP Macro detailed output with errors and warnings Shift F6 OMAN oarwh 4 22 05 11 RUNNING ENERGYPLUS EP LAUNCH PROGRAM 4 22 05 19 MAP daylighting illuminance map Shift F7 20 TABLE tabulated report of bin and monthly data in comma tab or space delimited or HTML format Shift F8 21 CFP Constrained free parameters for optimization not implemented in EnergyPlus v1 1 1 Shift F9 22 SCI cost information report not implemented in EnergyPlus v1 1 1 Shift F11 23 DXF drawing file in AutoCAD DXF format Shift F12 Clicking on the Drawing File button will open the generated DXF file if an appropriate viewer has been configured see Selecting Viewers and Editors below The DXF file is a CAD format that displays the physical shape of the building being modeled in three dimensions The Drawing File button also opens the HVAC diagram generated with the HVAC Diagram utility see Auxiliary Programs Clicking on the Spreadsheets buttons will open any generated CSV files if an appropriate viewer has been configured see Selecting Viewers and Editors below Viewing the Drawing File without Running a Simulation The Drawing button or the View menu Drawing File option will automatically run WinEPDraw if the DXF file does not exist or it is older than the input file This
42. e boxes next to each file to select the files to be simulated The path to files shown may be changed using the path button Once the files in a certain directory are selected the next button should be pressed If additional files are desired in different directories you will get a chance to add them to the EnergyPlus group file in a later step Select one or several weather files using the second step of the wizard shown below RUNNING ENERGYPLUS EP LAUNCH PROGRAM Step 2 of 5 Select Weather Files JC EnergyPlus wWeatherD ata Path USA_CA_ San Francisco_TMY2 epw USA_CO_Boulder_TMY2 epw USA_FL_Tampa_TMY2 epw USA_IL_Chicago DHare_TMY2 epw USA_WA_SterlingWW ashington Dulles_TMY2 epw Figure 6 Step 2 of New Group Wizard The next step is to review the simulations selected Each combination of weather file and input file is initially shown Each simulation is displayed as a single row You may select a row and delete the simulation at this point In addition if additional simulations are desired the Add more simulations button brings you back to the first step of the wizard to add more file ia New Group of Simulations xj Step 3 of 5 Review Simulations EX EC EnergpPlus E xampleFiles 1ZoneUncontrolled idf ic EnergyPlus San Francisco_TMY2 epw 2 C EnergyPlus E xampleFiles 1ZoneUncontrolled idf C EnergyPlus WeatherData USA_CO_ Boulder TMY2 epw
43. e of that air volume EnergyPlus calculates the energy required to maintain each zone at a specified 24 INFORMATION NECESSARY TO RUN ENERGYPLUS A METHODOLOGY FOR USING ENERGYPLUS 4 22 05 temperature for each hour of the day Since EnergyPlus performs a zone heat balance the first step in preparing a building description is to break the building into zones The objective of this exercise is to define as few zones as possible without significantly compromising the integrity of the simulation Although defining building zones is somewhat of an art a few general rules will keep the new simulation user out of trouble Consider the following figure which shows the floor plan of the Ft Monmouth Education Center Figure 5 Fort Monmouth Education Center The question is How many thermal zones should be used to model this building The inexperienced building modeler may be tempted to define each room in the building as a zone but the thermal zone is defined as a volume of air at a uniform temperature The general rule then is to use the number of fan systems and radiant systems not the number of rooms to determine the number of zones in the building The minimum number of zones in a general simulation model will usually be equal to the number of systems serving the building The collection of heat transfer and heat storage surfaces defined within each zone will include all surfaces bounding or inside of the space con
44. e tool bar Class List and Objects The classes that can be used to make up an IDF file have been organized into groups as shown in the Class List portion of the screen A class is made up of a group of objects Select a class from the list by clicking on and highlighting the class The field to the left of the selected class in the Class List will either contain to indicate that this class has no objects in the IDF file or it will contain a number like 003 to indicate the number of times the object currently appears in the IDF file For example for the SURFACE class selected in the screen above under the ZONE group there are 8 objects in the IDF file The details for these 8 objects or any new object that is defined are displayed in columns within the grid Each 40 CREATING INPUT FILES IDFEDITOR 4 22 05 object is made up of fields and can be used to further define the object Any units attached to each field are shown in the second column You may need to scroll down the field list or maximize the application to see all of the fields Likewise you may need to scroll to the right of the main grid to see other objects Changing Values By clicking and highlighting a value within an object several things happen 1 Any user comments from the IDF file will be displayed in the Comments from IDF portion of the screen 2 Any notes contained in the IDD for this input field will be displayed in the E
45. eriod 53 ExteriorEquipment Coal J RunPeriod 64 ExteriorEquipment FuelOil 1 J RunPeriod 75 ExteriorEquipment FuelOil 2 J RunPeriod 86 ExteriorEquipment Propane J RunPeriod 97 ExteriorEquipment Water M3 RunPeriod End of Data Dictionary 1 CHANUTE AFB ILLINOIS SUMMER 40 30 88 13 6004 229 251 57 A gt a 26 2 4441696E 10 0 0000000E 00 7 21 1 01 10 1 0543500E 08 7 21 18 51 60 42 8 6400000E 07 600000 0 7 21 1 01 10 600000 0 7 21 1 01 10 53 8 6400000E 07 600000 0 7 21 1 01 10 600000 0 7 21 1 01 10 64 8 6400000E 07 600000 0 7 21 1 01 10 600000 0 7 21 1 01 10 75 8 6400000E 07 600000 0 7 21 1 01 10 600000 0 7 21 1 01 10 86 8 6400000E 07 600000 0 7 21 1 01 10 600000 0 7 21 1 01 10 97 9 5040000E 08 600000 0 7 21 1 01 10 6000000 7 21 1 01 10 301 2 4355291E 10 0 0000000E 00 7 21 1 01 10 1 0543500E 08 7 21 18 51 60 306 7 0114299E 09 0 0000000E 00 7 21 1 01 10 1 0543500E 08 7 21 18 51 60 311 7 7724027E 09 0 0000000E 00 7 21 1 01 10 5 9570756E 07 7 21 24 51 60 316 9 5714509E 09 0 0000000E 00 7 21 1 01 10 1 0543500E 08 7 21 18 51 60 26 2 4441696E 10 0 0000000E 00 7 21 1 01 10 1 0543500E 08 7 21 18 51 60 The previous line shows the output for 26 the Electricity Facility meter for the entire run period which is just a summer design day The second value 2 4441696E 10 is the recorded usage for that run period The third value 0 0000000E 00 is the minimum value re
46. es results that can then be fed into an LCC program In general calculations of this nature are better left to smaller utility programs which can respond more quickly to changes in escalation rates and changes to methodologies as prescribed by state federal and defense agencies gt EnergyPlus is not an architect or design engineer replacement It does not check input verify the acceptability or range of various parameters expect for a limited number of very basic checks or attempt to interpret the results While many GUI programs assist the user in fine tuning and correcting input mistakes EnergyPlus still operates under the garbage in garbage out standard Engineers and architects will always be a vital part of the design and thermal engineering process Why does EnergyPlus exist and what were its original goals 4 22 05 The existence of EnergyPlus is directly related to some of the increasingly obvious shortcomings of its predecessor programs BLAST and DOE 2 Both programs though still valid tools that will continue to have utility in various environments have begun to show their age in a variety of ways Both BLAST and DOE 2 were written in older version of FORTRAN and used features that will eventually be obsolete in new compilers Both programs consisted of a significant amount of spaghetti code and outdated structures that made it 2 ENERGYPLUS OVERVIEW WHY DOES ENERGYPLUS EXIST AND WHAT WERE ITS ORIGINAL GO
47. esneneaeenenaes 8 Running Energy PUS 02 A bedtes heer as dee beset eet eae veld 9 INTOdUCIO Nas aa o dt is AEAEE 9 EP Launch Program csi aledetetediete Madieaniaasbieleiandesenennaaslan 9 Figure 3 EP Launch SON qc ls 10 Starr LUN dd e 10 Selecting Input and Weather Files ooo occconnncccnnnnnccccnncnoncccnnnnanccnnnnnnnnos 10 Running a Single SIMI oda 10 Looking atihe ResullS coast ea akian aaka aE os kaanin E 11 Figure 4 EP Launch Finish Status secocvcociisimsansicadse agrario cecilia 11 Viewing the Drawing File without Running a Simulation 12 Editing the Input csi det 12 Selecting Viewers and Editors oooooccconnnnccccnnonccccncnoncnccnnnnncnnnnnnanrnnnnnnn nao 12 Pile Men cita 13 Edit Men sisp datada 13 A E 13 4 22 05 TABLE OF CONTENTS Figure 3 EP Launch View Menu ccccceeeeeeeseeeeeeneeeeeeeneeseeeeeeee 13 Help MU ion N nanea aE aaoi aSa 14 Recently Used FileSend a ea eaae i ani 14 Running Groups of Simulations ooooonoccccnnnocccicononccnncnonanancnnnna cnn nnnnncnnns 14 Figure 4 Group of Simulation Tab oococcconncccccnnoncccncnoncnancnnnnancnonananccnnos 15 Figure 5 Step 1 of New Group Wizard ccoooocccccnonocincconcocccnnanancccnnnnnncnnns 15 Figure 6 Step 2 of New Group Wizard ccoooocccccconoccccnonanaccncnnanccnnnanancnnns 16 Figure 7 Step 3 of New Group Wizard ccoooocccccconocccccoccoaccnnannccnnnnnnncnnn 16 Figure 8 Step 4 of New Group Wizard c ccoo
48. face temperatures on both sides of the surface are the same This means that even though heat may be stored in a partition ceiling or floor no heat flows through it Heat Storage Surfaces Use current Surface name for ExteriorEnvironment e g Surface HeatTransfer Zn005 Wal1006 Base Surface Name Wall INTERIOR Class and Construction Name MAINE WING Zone OtherZone Zn005 Wal1006 l Exterior Conditions and Target if applicable NoSun Solar Exposure NoWind Wind Exposure 0 5000000 VF to Ground 4 Rectangle 57 90000 j 57 79000 j 10 00000 57 90000 7 57 79000 0 0000000E 00 57 90000 j 47 79000 0 0000000E 00 57 90000 2 47 79000 j 10 00000 28 INFORMATION NECESSARY TO RUN ENERGYPLUS A METHODOLOGY FOR USING ENERGYPLUS 4 22 05 Some surfaces divide the temperature controlled space from the outside environment Surfaces that are both sun and wind exposed e g exterior walls exposed floors roofs feel the full effect of both solar radiation and outside temperature and the outside air film resistance for these surfaces changes with wind speed and wind direction Surfaces that are not sun or wind exposed a wall to an uncontrolled space are not affected by solar radiation wind speed or direction and have a constant outside convective air film resistance Heat Transfer Surfaces Exposed to the Outside Environment such as Exterior Walls Roofs Exp
49. faces For testing and development purposes however it can be run stand alone without such an interface This document describes how to run EnergyPlus in such a stand alone fashion If you are not familiar with building modeling and simulation programs please review the section Information necessary to Run EnergyPlus first and then come back to this section Like all simulation programs EnergyPlus consists of more than just an executable file EnergyPlus needs various input files which describe the building to be modeled and the environment surrounding it The program produces several output files which need to be described or further processed in order to make sense of the results of the simulation Finally even in stand alone mode EnergyPlus is usually not executed by hand but rather by running a procedure file which takes care of finding input files and storing or further processing the output files To assist those not familiar with the DOS Command Line or batch files we have included the EP Launch program Review the next section for instructions If you wish to learn about DOS Command Line use for EnergyPlus skip to section RunEPlus batch file EP Launch Program 4 22 05 EP Launch is an optional component of the EnergyPlus installation For users that want a simple way of selecting files and running EnergyPlus EP Launch provides this and more In addition EP Launch can help open a text editor for the input and ou
50. gyPlus versions 1 2 and later is the HVAC Diagram application It reads one of the EnergyPlus output files eplusout ond and produces a Scalable Vector Graphics SVG file More information on the HVAC Diagram program is found in the Auxiliary Programs document This simple post processing program uses csv files Such as created by ReadVarsESO and performs some simple statistics on the contents This program is described more fully in the Auxiliary Programs document 49 DATAFILES LIBRARY FILES DataFiles Some example files are installed during installation Sample Files option Each sample input file should contain comments about its purpose at the start of the file Other example files are made available from the website http www energyplus gov HVAC Templates are installed with the sample files option More information about the use of HVAC templates is contained in the Auxiliary Programs document Library Files Library files for EnergyPlus are embodied in the DataSets and MacroDataSets folders DataSets are IDF excerpts you must cut and paste from them in order to use them Items in MacroDataSets can be used in conjunction with the EPMacro preprocessor program All files are in the necessary form for processing with EnergyPlus The files in the DataSets and MacroDataSets folders are described in more detail in the Output Details and Examples document 4 22 05 50 ENERGY METERS LIBRARY FILES Energy Mete
51. he input data file Energy idd the data dictionary file n epw the weather file needed only if there is a RunPeriod in the input and optionally Energy ini the initialization file Typing EnergyPlus and hitting the Enter key will execute the program EnergyPlus will write messages to the command window as it runs A simulation with two design days and one run period looks like EnergyPlus Starting EnergyPlus Version 1 2 1 Initializing New Environment Parameters Warming up Initializing Response Factors Calculating CTFs for EXTWALL80 Construction 1 Calculating CTFs for PARTITIONO6 Construction 2 Calculating CTFs for FLOOR SLAB 8 IN Construction 3 Calculating CTFs for ROOF34 Construction 4 Initializing Window Optical Properties Initializing Solar Calculations Initializing HVAC Warming up Warming up Warming up Starting Simulation at 07 21 for CHANUTE AFB ILLINOIS SUMMER Initializing New Environment Parameters Warming up Warming up Warming up Warming up Starting Simulation at 01 21 for CHANUTE AFB ILLINOIS WINTER EnergyPlus Run Time 00hr 00min 9 87sec When execution is finished ep usout err and eplusout audit will always appear If the program terminated with an input error these may be the only output files If the program runs normally eplusout eio will appear Depending on what was requested in the input the other output files described above will also be written 20 RUNNING
52. ile maps the geometry of relevant object instances to EnergyPlus objects and writes an EnergyPlus IDF This is not an interactive process in which the user can intervene to make changes or additions to the resulting IDF A simple host graphical user interface GUI application has also been developed that allows an end user to specify the IFC data file to be read and the IDF to create The GUI and the DLL run on the Microsoft Windows 95 98 NT platforms The utility is built upon and requires the installation of the BSPro COM Server software package developed by Olof Granlund Oy of Finland see www bspro net and Section 5 2 in the IFCtolDF user manual The BSPro COM Server software would be necessary for you to extract the geometry information from an IFC compliant tool If you choose the IFCtolDF utility the BSPro COM Server is installed as well The IFCtolDF utility is primarily intended as an example of the capability of developing interoperability between commonly available software e g CAD tools and EnergyPlus using the IFC data model It is anticipated that as more software tools become IFC compliant the capabilities demonstrated in the IFCtolDF utility will be incorporated into a variety of other software including specialized user interfaces for EnergyPlus Text Editor Text editors such as NOTEPAD can also be used to edit an IDF file Do not use tabs or other special characters in the IDF file as EnergyPlus will not convert these
53. ion document both of these are under the Enhancing EnergyPlus Tab of the EnergyPlus Documentation Menu It is also described in the Encyclopedic Input Output Reference document Output Files More information and more up to date about output files is shown in the Output Details and Examples Document eplusout err A text file containing the error messages issued by EnergyPlus This is the first output that should be examined after a simulation Error messages may be issued by EnergyPlus during its input phase or during the simulation There are three levels of error severity fatal severe and warning as well as simple message lines A fatal error causes the program to terminate immediately The following table illustrates the necessary actions 21 RUNNING ENERGYPLUS ENERGYPLUS FILES 4 22 05 Table 1 Error Message Levels Required Actions Error Level Message Informative usually a follow on to one of the others No action required Warning Take note Fix as applicable Should Fix Program will abort An example of an error message due to an input syntax error is kk Severe Did not find DessignDay in list of Objects Fatal Errors occurred on processing IDF file probable incorrect IDD file View audit out for details RRA RRRARARAR EnergyPlus Terminated Error s Detected eplusout audit This is an text file which echoes the IDD and IDF files flagging synt
54. its of the structural improvements over the legacy programs is that the code can now be much more object oriented and modular in nature A result of the goal for improved structure in EnergyPlus was the definition of a well organized module concept that would facilitate adding features and links to other programs It was decided that FORTRAN9O would be used for the initial release of EnergyPlus due to the fact that it e sa modern modular language with good compilers on many platforms e allows C like data structures and mixed language modules e provides structure that begins to be object based e allows long variable names up to 32 characters e provides backward compatibility with legacy code during the development process The key benefit of modularity is that researchers can develop modules concurrently without interfering with other modules under development and with only a limited knowledge of the entire program structure This feature is critical to promoting both widespread use and broad development of program models EnergyPlus can only be successful if the pool of potential model developers increases significantly so that interest and economics drives what models are added to the program rather than have its extensions limited by a lack of intellectual 3 ENERGYPLUS OVERVIEW WHY DOES ENERGYPLUS EXIST AND WHAT WERE ITS ORIGINAL GOALS 4 22 05 Ground Ht Transfer e Models Condition resources Thus modularity and stru
55. j buttons see the Working with Objects section above In addition the Next Row after Enter option can be toggled When this option is on the selection moves down one row after pressing Enter The copy and paste object commands allow a single object to be copied within a file or between files The pasted object appears as the last object in the class This capability makes it easier to utilize the data in the DataSets directory View Menu The View menu offers options for units and column widths The Narrow Medium Wide Column options set the standard column width for items in the object grid Individual columns can also be resized by dragging the column separator The displayed value is rounded and or expressed in scientific notation to fit within the column width EnergyPlus input files must always be in SI units and the IDF Editor always opens in SI units mode Selecting Inch Pound IP units in the View menu displays and edits values in IP units IP units are only partially supported 1 Fields with no units specified are not converted This includes all schedules and fluid properties If a field has no units displayed in the units column of the object grid then no conversion will be made 41 CREATING INPUT FILES BLASTTRANSLATOR Note that thermostat setpoints people activity levels and other dimensioned schedules must always be entered in SI units even when the IDF Editor is in Inch Pound mode These objects which have n
56. l Documentation the PDF files of the documentation DataSets Reference Data Sets MacroDataSets Data sets that are macroized PreProcess IDFEditor Program files for the IDFEditor BLASTTranslator RunXLate batch file for executing the BLASTTranslator Sample file described in this section both BLAST versions and IDF versions Libraries the executables and libraries for the BLASTTranslator DOE2Translator IFCtoIDF Program to convert IFC compliant files CADD etc to EnergyPlus input format GrndTempCalc Special program to calculate ground temperatures WeatherConverter EnergyPlus weather conversion reporting program Can transform files into EnergyPlus EPW format as well as Comma delimited CSV and small statistical reports PostProcess ReadVarsEso The simple post processor exe ExampleFiles Sample input output results files shipped with the program WeatherFiles Sample weather files shipped with the program Templates Input templates to assist in HVAC file creation 4 22 05 8 RUNNING ENERGYPLUS INTRODUCTION Running EnergyPlus Introduction EnergyPlus is a simulation program designed for modeling buildings with all their associated heating ventilating and air conditioning equipment EnergyPlus is a simulation engine normally it would be used in conjunction with a graphical user interface When graphical interfaces become available input files will typically be created using these inter
57. l gains for the thermal zone These gains are described to EnergyPlus as a design or peak level with a schedule that specifies a fraction of the peak for each hour The peak level is 4 22 05 34 INFORMATION NECESSARY TO RUN ENERGYPLUS A METHODOLOGY FOR USING ENERGYPLUS 4 22 05 calculated by the user Table 6 Table 6 Internal Gain Data Gain Type Size Schedule 1 Office occupancy Office lighting Infiltration 1570 Constant The column headings in the table have the following meanings Gain Type The code used to differentiate between various types of internal gains Internal Gain Data shows the internal loads for a single zone model of Ft Monmouth and the schedule named to specify the hourly load Size The peak load This is the actual size of the load for every hour that the schedule specifies 100 Schedule The hourly schedule that specifies the percentage of peak load for each hour of the day 35 CREATING INPUT FILES IDD CONVENTIONS Creating Input Files EnergyPlus has several options for the user to create input files One of the goals of EnergyPlus was to make a simple readable input file for the program More of this background and explanation is contained in the Interface Developer s Guide Understanding the Input Data Dictionary IDD is the key to reading the input file We have set some conventions for commenting the IDD so that the units minimum maximum
58. le To use the DOE2Translator program at the DOS prompt or the command prompt for Windows NT 2000 systems go to the directory that the DOE2Translator is located That directory is likely to be c EnergyPlus PreProcess DOE2Translator In this directory there should be several files DOE2Translator exe the program D2E_macr txt a support file that contains the header of the translated file D2comkey dat a support file that contains a list of DOE 2 keywords Samp4n inp sample DOE 2 1E input file Samp4n imf the EnergyPlus macro input file resulting from the sample To use the DOE2Translator simply type DOE2Translator lt file gt Where you substitute the file you want to translate for lt file gt without a file extension The inp file extension is assumed For example if you want to translate one of the sample DOE 2 1E input files you would type DOE2Translator samp1b The lt file gt can also have a full path but it should not have an extension Several files get created when you run the DOE2Translator program In the same directory as the DOE 2 1E input file a new file with the same name and the file extension of imf contains the EnergyPlus translation This is an EnergyPlus macro file and the macro processor EPMacro needs to be used The DOE2Tranlator uses many macros so using EPMacro is essensial EP Launch automatically runs EP Macro when an imf file is selected In the translated file comments shown with a tilde
59. les within the EnergyPlus structure and framework Programming Standards This document is the source of all major policies relating to the actual EnergyPlus source code It describes rules to which all program code should adhere notes how to structure and modularize code and provides a listing of approved input and output units As a result it is an important document for both interface and module developers Interface Developer s Guide This document is critically important to persons interested in developing an interface that provides input to and read output from EnergyPlus It is a comprehensive guide to the input data dictionary and the input data files that contain a user s building data Each piece of input syntax is described in detail In addition the mechanism for obtaining output and the format in which output will be produced are discussed This document also contains sections on weather files and units Numerous samples and examples are given throughout the document with a full file length example provided in the appendix Module Developer s Guide This document contains a wealth of information that is intended to provide as much assistance as possible to persons interested in adding modules to the EnergyPlus program It reviews the module concept as outlined in the programming standard and how they have been implemented in EnergyPlus It provides a description of how the various modules work together and how the program is
60. level of confidence in the results produced by EnergyPlus EnergyPlus Documentation Library Below are brief descriptions of the various components of the EnergyPlus Documentation Library User Information Documents The following documents relate to using EnergyPlus the engine These documents cover a full range of questions and should be the first place a beginning or even experienced user would go to find out how the program works what it expects as input what it produces as output etc In general the information in these documents is not highly technical but it is detailed enough to use the basic capabilities of the program Getting Started with EnergyPlus You are currently reading the Overview section of this document The overview contains a big picture description of the EnergyPlus program as well as background of its development and the goals to which it ascribes The remainder of the Getting Started document provides beginning users with an introduction into how to run EnergyPlus what files are needed for EnergyPlus to execute and what files are produced when EnergyPlus runs successfully It also provides some guidance as to how to determine what potential sources of errors are when EnergyPlus runs into problems and how serious those problems might be Input and Output Reference This document is a thorough description of the various input and output files related to EnergyPlus the format of these files and how the file
61. o units field will not be converted 2 The IP unit will be displayed in the units column of the object grid Some SI units convert to multiple IP units For example W becomes Btu hr for heating and cooling capacity but remains as W for lighting and electrical equipment 3 All conversion factors used in the IDF editor are documented in a block of comments near the top of the Energy IDD file Help Menu The Help menu offers options to open the EnergyPlus documentation files Caveats Remember to save any changes made before you create or edit another input file No Run EnergyPlus button is available Save your IDF file and use EP Launch to execute an EnergyPlus run You cannot edit comments in the Comments from IDF section of the screen All engineering units are in SI IP units have not been implemented yet The use of point or comma as the decimal symbol is controlled by the windows system settings This setting is found in the Control Panel Regional Options Number tab Decimal Symbol field IDF Editor will use the current decimal symbol to signify the start of the fractional portion of the number and will ignore other symbols The idf file is always written using point as the decimal symbol Bugs Please report any bugs to the energyplus support gard com address so that we can fix them prior to the next release BLASTTranslator 4 22 05 The BLAST Translator will produce an IDF file from an existing
62. ode just to make an addition to a very limited part of the program This goal was achieved through a program structure that implemented a manager philosophy In effect the program consists of many pieces i e modules see next paragraph which when viewed graphically resemble an inverted tree Instead of allowing lower level pieces of the program and calls to those sections of the code to infiltrate up to the highest level of the simulation each branch exercises control over when its sub branches are called Thus this is much like an organization chart where management over employees proceeds up a chain of command until it reaches the CEO of the simulation In EnergyPlus a subroutine called ManageSimulation serves the CEO role This single subroutine controls four of the five main simulation loops environment day hour sub hour time step the system time step is controlled by the HVAC manager In addition this subroutine also sets global flags that are used by other subroutines and modules to determine the state of the simulation so that each part of the program knows whether to read input initialize simulate report etc The manager philosophy makes the links between program modules simple and explicit Typically each module is accessible only through a call to its manager routine Developers no longer have to worry about hidden and unexpected connections between and among program subroutines Modularity One of the benef
63. ol strategy for each area of the building V Obtain sufficient HVAC operation information to allow specification and scheduling of the fan systems V Obtain sufficient central plant information to allow specification and scheduling of the boilers chillers and other plant equipment Step 2 Zone the Building A building surface is the fundamental element in the building model In the general sense there are two types of surfaces in EnergyPlus These are 1 heat transfer surfaces and 2 heat storage surfaces The first rule of building modeling is Always define a surface as a heat storage surface unless it must be defined as a heat transfer surface Any surface which is expected to separate spaces of significantly different temperatures must be defined as a heat transfer surface Thus exterior surfaces such as outside walls roofs and floors are heat transfer surfaces Interior surfaces partitions are heat storage surfaces if they separate spaces maintained at the same temperature and heat transfer surfaces if they separate spaces maintained at different temperatures A discussion of how to define heat transfer and heat storage surfaces will occur in later steps In order to correctly zone the building it is necessary only to distinguish between the two A zone is a thermal not a geometric concept A zone is an air volume at a uniform temperature plus all the heat transfer and heat storage surfaces bounding or insid
64. oocccccconociccconcncccnnanancncnanancncnos 17 History of Simulations PerforMed ooooooccccnnnocccccononcncncnonanancnnnnanccnnnnnnccnnns 17 Figure 9 History Tabo io 18 AW CLS 52 Akad ce hag Se aa a tare DON ee Oa ect ae cal ata 18 When things gO Wrong merda dans 19 Figure 10 EnergyPlus crash within EP Launch sss 19 A O 19 RUnEP IWS Dates a UE blade ate 20 Running EnergyPlus by Hand iria aainsde 20 Energy Plus Fleur ds 21 INPUE E TE E 21 OUTPUT Fils sii ree iea calentado ed 21 Table 1 Error Message Levels Required AcCtiONS oooocoonincnonccccniccos 22 Postprocessing Program Files ent ee wae eineds 23 Information necessary to Run EnergyPlus ccssccescececceseeeeeeeeeeeeseeeeeeeeeeeeeeneeees 24 Building SIMIO ss ns 24 A Methodology for Using Energyplus cccceeeeeeeeeeeeeeeceeeeeeeeeeeeeeeneee 24 Siep A eek Sa I ee Sires aes 24 4 22 05 TABLE OF CONTENTS Step 2 Zone the BUlAMi oda 24 Figure 5 Fort Monmouth Education Center ccccconnnococccccnnnnnnnninnannnnnos 25 Table 2 Zoning the Building by System TyPB oooocccnccccccnnoncccccccnanancccnnns 26 Figure 6 Thermal Zones in the Education Center ooooocccccccccccccnoconnnnnos 26 Figure 7 Single Zone Model of the Ft Monmouth Education Center 27 Step 3 Prepare to Construct the Building Model oooooooooccccccccccccnnccnccooo 27 Table 3 Surface types and categorization c sceccccceccessssseeeteeeeeeees 28
65. or 2 User supplies name for the element 3 Abbreviate as found in the BLAST Standard libraries 4 Material s full name is as found in the BLAST Standard libraries Step 3 4 Compile surface and subsurface information Building information 1 Building North Axis This syntax simplifies building geometry specification by designating one wall of the building as the building s north pointing axis The building model North axis is measured from true compass North Surface facing angles see surface information below are then specified relative to the building north axis The North Axis entry in the BLAST User Reference illustrates specification of the building north axis Zone information 1 Wall height This is entered once All walls are assumed to be the same height If the height for a given wall differs from the specified height the wall length should be adjusted by the user to give the correct equivalent area In certain conditions this may not be possible and you will need to resize each wall accordingly Surface information 1 Base Surface Type Heat Transfer Heat Storage Surfaces may be of the following types wall floor roof internal mass or subsurface 2 Construction The type of construction of the surface see previous table Subsurface information 1 Subsurfaces are Windows Doors or GlassDoors 2 Area Area of the subsurface 3 Reveal For windows only the distance it is inset from the outside surf
66. osed Floors Surface HeatTransfer Zn005 Wall002 Base Surface Name Wall EXTERIOR Class and Construction Name AINE WING l Zone ExteriorEnvironment Exterior Conditions and Target if applicable SunExposed Solar Exposure WindExposed Wind Exposure 0 5000000 gt VF to Ground 4 Rectangle 77 90000 A 47 79000 A 10 00000 A 77 90000 7 47 79000 0 0000000E 00 77 90000 67 79000 0 0000000E 00 77 90000 A 67 79000 A 10 00000 A Surfaces such as basement walls and slab floors separate the space from the earth surrounding the surfaces Therefore the outside surface temperatures become the ground temperatures Heat Transfer Surfaces in Contact with the Ground such as Basement Walls or Slab Floors Surface HeatTransfer Zn004 F1r001 Base Surface Name Floor SLAB FLOOR Class and Construction Name ARIZONA WING Zone Ground Exterior Conditions and Target if applicable NoSun Solar Exposure NoWind Wind Exposure 1 000000 P VF to Ground 4 Rectangle 38 01000 A 8 510000 0 0000000E 00 18 01000 7 8 510000 0 0000000E 00 18 01000 A 28 51000 0 0000000E 00 38 01000 A 28 51000 0 0000000E 00 Other surfaces separate zones that may be at different temperatures These surface types allow heat transfer by conduction through the walls from a zone at a higher temperature to a zone at a lower tem
67. perature The location of the heat storage surface in the zone is not important except in specialized solar studies The surface above wall to uncontrolled space would be more correctly modeled as an interzone surface Heat Transfer Surfaces Exposed to Another Zone such as Interzone walls ceilings or floors Surface HeatTransfer Zn005 Wall005 Base Surface Name Wall INTERIOR Class and Construction Name MAINE WING Zone OtherZone 2n001 Wa11009 Exterior Conditions and Target if applicable NoSun Solar Exposure NoWind Wind Exposure 0 5000000 P VF to Ground 4 Rectangle 57 90000 j 47 79000 7 10 00000 j 57 90000 47 79000 0 0000000E 00 67 90000 A 47 79000 0 0000000E 00 67 90000 2 47 79000 gt 10 00000 29 INFORMATION NECESSARY TO RUN ENERGYPLUS A METHODOLOGY FOR USING ENERGYPLUS 4 22 05 Step 3 2 Define equivalent surfaces as desired When the building was zoned our objective was to define as few zones as possible Now we would like to extend this objective to include defining as few surfaces as possible without significantly compromising the integrity of the simulation We reduce the number and complexity of surfaces in our input file by defining equivalent surfaces Before dealing with equivalent surfaces it is appropriate to take the concept of a thermal zone one step further EnergyPlus performs heat balances on individual zone
68. properly EPMacro The EPMacro auxiliary program described in the Auxiliary Programs document has an easily understood macro language You can use EPMacro to take pieces of commonly used 4 22 05 44 CREATING INPUT FILES HVAC TEMPLATES data such as location or design day information and merge this into the final input file Or you can use it to select this information from one of the supplied library data sets HVAC Templates The HVAC templates are described in detail in the Auxiliary Programs Document Compact HVAC Objects Beginning with the V1 2 2 release compact HVAC objects are available These are intended to allow for several usual HVAC types to be expanded into EnergyPlus HVAC inputs with minimal user entries These are described in the Input Output Reference document under the Group Compact HVAC and the expansion process is described in the Auxiliary Programs document under ExpandObjects Data Sets EnergyPlus uses snippets of IDF files to create the library of data that may be useful for you Two folders are created upon installation DataSets which contains IDF snippets and MacroDataSets which also contain IDF snippets but are in a form such that they can be easily used with the EPMacro program Slab and Basement Programs The Slab and Basement programs can be used to create accurate Ground Temperature profiles for your runs using minimal input about your building These are use
69. r IDF Editor is an optional component of the EnergyPlus installation For users who want a simple way of creating or editing EnergyPlus input data files IDF IDF Editor provides this service The IDF Editor does not check inputs for validity although some numeric fields are highlighted if out of range For instructions and rules that must be followed when creating an IDF file the user should refer to the Input Output Reference document 4 22 05 39 CREATING INPUT FILES IDFEDITOR fq IDF Editor C EnergyPlus 12ZoneUncontrolled idf l 0 xj File Edit view Help peale AES New Obi Dup Obi Del obi Class List a Surface HeatTransfer Sub Comments from IDF EnergyPlus 1 1 0 015 MATERIAL WINDOWSHADE a MATERIAL WINDOWBLIND MATERIALPROPERTY MOISTURE MTF MATERIALPROPERTY MOISTURE EMPD mi WindowGlassSpectralD ata 001 CONSTRUCTION CONSTRUCTION WITH INTERNAL SOURCE CONSTRUCTION FROM WINDOWS DATA FILE zi Thermal Zone Description Geometry Explanation of Keyword ID 42 Select from list of choices aa Surface Shading Detached Fixed eme Surface Shading Detached Building y zi Surface HeatT ranster InternalMass Obj2 Obj3 Obj4 2n001 Wall003 2n001 Wwall004 User Supplied Surface Name 2n001 Wall001 Z2n001 wall02 Surface Type Wall Wall Wall Construction Name of the Su
70. re using version About the Crash You may not see any error messages in the output files since EnergyPlus may have crashed before the messages were written This condition is often the result of an input value of zero when a non zero number was expected invalid geometry misconnected nodes an invalid component arrangement or missing components If you have run this input file previously and modified it you may want to examine the modifications carefully Experienced Users If you are an experienced EnergyPlus user you may want to activate Pause During Simulation under the View menu and see the name of the software routine in use when the crash occurred This is the first routine mentioned in the message after the crash The name of the routine may help you determine what may have caused the crash Figure 10 EnergyPlus crash within EP Launch Bugs The EP Launch program has been through several releases but there is still a chance you will find bugs Please report them to the energyplus support gard com address so that we can fix them prior to the release If the pull down lists ever are shown as blank the reset button may be used This unlabeled button is very small in the lower left hand corner of the main screen It removes the items shown in the recently used file list and causes the program to forget the selected viewers and text editors and exits the program When you start EP Launch again you will need to make
71. rface Developers to embody these kinds of databases within their user friendly programs In many cases the EnergyPlus team will be helping this development by supplying Reference Data Sets RDS such as equivalent IDF constructions and materials for all the BLAST or DOE 2 libraries Even then the EnergyPlus Input Data File will likely be a complete file all elements needed to run the simulation will be incorporated into the single Input Data File IDF The following table uses names of materials that are contained in the BLAST libraries Like BLAST EnergyPlus requires that materials are listed from the outside to the inside of the zone The following table shows the construction elements for the Education Center 1 2 3 4 4 IN DENSE FACE BRICK lo INHWOONCRETEBLOCK o op m3 MINERALFIBERFIBROUS6IN 2 Partition const2 Pla GYPSUMLWAS 8IN o po a 4INDENSEFACEBRICK lo po 8INHWCONCRETEBLOCK OOOO GYPSUMLWAS 8IN__ 31 INFORMATION NECESSARY TO RUN ENERGYPLUS A METHODOLOGY FOR USING ENERGYPLUS 4 22 05 A A O TA a orci pT B INHWOONGRETE BLOCK ee ne es se pT int EXPANDED EXT POLYSTYRENE R122 IN PT CT es CElINGAIMSPACE at leer acousricmies 4IN___ IN a E co17 CONCRETE DRIED SAND AND GRAVEL 4 IN FFS FINISH FLOORING TILE 1 16 IN Table 4 Building Elements Notes 1 The surface type is either a wall floor roof window or do
72. rface current i RISWALL RISWALL InsideFaceEnvironment reference ZONE ONE ZONE ONE DutsideFaceEnvironment reference mF ExteriorEnvironment ExteriorEnvironment DutsideFaceEnvironment Object reference Sun Exposure reference SunExposed SunExposed Wind Exposure WindE xposed WindE xposed WindExposed WindExposed View Factor to Ground 0 5 0 5 0 5 0 5 Number of Surface Vertex Groups Num 4 4 4 4 Vertex 1 X coordinate m 0 15 24 15 24 0 Vertex 1 Y coordinate m 0 0 15 24 15 24 Vertex 1 Z coordinate m 4 572 4 572 4 572 4 572 Vertex 2 X coordinate m 0 15 24 15 24 0 4 22 05 Figure 10 IDF Editor Screen Start IDF Editor IDF Editor should be located in the EnergyPlus PreProcessor IDFEditor directory where you installed EnergyPlus By double clicking on the IDF Editor icon you will get a screen similar to the one shown above This is the only screen that the IDF Editor uses IDF Editor works in conjunction with the current EnergyPlus Input Data Directory IDD file that resides in the directory where EnergyPlus is installed Another way to start the IDF Editor is from EP Launch Creating or Selecting an Input Data File Creating a new input data file or selecting an existing input data file can be accomplished either through use of the File menu on the menu bar at the top of the screen or through use of the New File icon button or Open File icon button on th
73. rly 94 2 MIDDLE FORK Lights Return Air Heat Gain J Hourly 95 2 MIDDLE FORK Lights Radiant Heat Gain J Hourly 98 2 MIDDLE FORK Lights Total Heat Gain J Hourly 99 2 MIDDLE FORK Lights Electric Consumption J Hourly 100 2 RIGHT FORK Lights Return Air Heat Gain J Hourly 101 2 RIGHT FORK Lights Radiant Heat Gain J Hourly 104 2 RIGHT FORK Lights Total Heat Gain J Hourly 105 2 RIGHT FORK Lights Electric Consumption J Hourly End of Data Dictionary Each variable is uniquely specified by a number 6 18 19 etc or by the combination of object name in this case a zone and variable name The eplusout inp file could alternatively been specified as eplusout eso eplusout csv 6 21 27 33 39 45 26 32 38 44 50 0 eplusout csv This is the comma delimited file output from the postprocessor It contains data for selected variables from an ESO file It is a comma separated text file suitable for input to a speadsheet such as Excel rvi Files with the rvi extension are just eplusout inp files for a specific simulation input For instance GeometryTest rvi is the eplusout inp file for the simulation described by 48 POSTPROCESSING HVAC DIAGRAM GeometryTest idf Since each rvi file makes sense only relative to a specific input the rvi files are generally stored in the same directory as the input IDF files HVAC Diagram CSVProc 4 22 05 Another post processing program Ener
74. roup C EnergyPlus1 2 021 new epg Browse Edit i Simulate Group EnerayPlus 1 1 1 008 Exit 4 22 05 14 RUNNING ENERGYPLUS EP LAUNCH PROGRAM 4 22 05 Figure 4 Group of Simulation Tab This tab lets you manage EPG EnergyPlus Group files which contain a list of simulations that need to be performed The EPG file is simply a text file that contains on each line the input file and weather file names to be used for a simulation along with how the output files should be named and a counter You do not need to manually create EPG files instead press the New Group button on the Group of Simulations Tab and a step by step wizard will help to create a new EPG EnergyPlus Group file The first step of the wizard is to selected the EnergyPlus input files that should be simulated as part of the group Fa ner Group or simueroas xi Step 1 of 5 Select Input Files ExEnerqyPlustExampleFiless Path E 1 ZoneUncontrolled idf 3zwent idf 3zventAutoCalcOfwindPressureCoefts idf 5Zone irCooled idf 5Zone uto idf EZone utoDXWAW idf 5ZoneBoilerDutsidedirReset idf 5ZoneDD idf EZoneDDCycOn ny idf 5ZoneDDCycOnOne idf 5ZoneE ngChill idf 5ZoneR etumPan idf EZoneSupRetPlen idf 5Zonewarmest idf 5ZonewaterCooled idf 5ZoneW aterCooled_HighRHControl idf OO OO OO Figure 5 Step 1 of New Group Wizard Use th
75. rs Meters will provide one way for EnergyPlus to report energy use in a form that is pallatable to the users The primary implemented method for output gives very fine detail down to the variable level for results from EnergyPlus However to get the required energy use there may be several variables that need to be polled and accumulated The meter implementation for EnergyPlus will accomplish this reporting Meters can be used to typify energy use by type and by component The following diagrams and tables will illustrate how the meters have been incorporated into EnergyPlus Elec Zone Elec HVAC Lights Zone O Building Sy tem Elec Plant Gas Plant Figure 11 Illustration for Energy Meters As shown in the figure above energy use for the facility is grouped according to fuel type see Table 11 Table of Metered Fuel Types by meter type see Table 10 Overall Meter Types and by end use category type see Table 12 End Use Category Types The developers place special calls which allow for the appropriate grouping and thence the accumulation of values For each simulation the meter names will be shown in the Report Variable Dictionary file Var Type Var Report Type Variable Name Units Zone Meter Electricity Facility J Zone Meter Electricity Building J Zone Meter Electricity Zone RESISTIVE ZONE J Zone Meter Electricity Zone EAST ZONE J Zone Meter Electricity Zone NORTH ZONE J Zone Meter GeneralLights
76. ry tab may be used to open files This option does not work when multiple weather files are selected C User Defined Location Place the output files in a custom user defined location Select this option if multiple weather files are chosen or if IMF files need to be simulated multiple times The Single Simulation tab will NOT open output files using this option instead use the History tab to open files The exact location that the output files will be written is defined below using the codes shown No extension should be included Location Zl input file name J input file path G group file name H group file path WN weather file name ZA weather file path Repeat IMF File Simulations 1 y ZN repeat number for IMF files Figure 8 Step 4 of New Group Wizard More advanced users may choose to define their locations for the output files using symbols that define the name of the directory and file name using l input file name G group file name W weather file name N repeat number for IMF files J input file path H group file path X weather file path Each of these symbols may be used in the location field and substitutions will be made for each when defining the output file location For macro files they have an extension IMF instead of IDF used in a parametric analysis the macro file may be run repeatedly up to 999 times Each time they are simulated a new COUNTER INC file is created which set
77. s a description of the loop based approach used by EnergyPlus to model the HVAC systems air loops water loops etc 6 ENERGYPLUS OVERVIEW DEVELOPER INFORMATION DOCUMENTS It includes a description of the higher level managers that control the simulation flow as well as some information on the various components that can be linked together to comprise an HVAC system HVAC Branch Based Input Description This section is a special extension of both the input document and the HVAC overview document It contains more detail on the various HVAC input objects and how these different object link together to form an HVAC description It contains vital information mainly for the interface developer but also provides users with an in depth look at the inner workings of the loop approach adopted by EnergyPlus Engineering Reference Appendix The appendix contains all other information that did not fit any of the previous categories listed above or was applicable across several major sections of code Readers should search the three documents listed above first before consulting the reference appendix Developer Information Documents The following documents will be most useful to potential developers of EnergyPlus both Interface Developers and Module Developers Interface Developers will be creating input and output wraps on EnergyPlus so that is it is usable to the architect design engineers and others Module developers will be creating new modu
78. s a macro parameter The COUNTER INC file should be included using the include statement in the macro file Finally you can save the EPG EnergyPlus Group file wherever you would like To run the simulations press the Simulate Group button on the Group of Simulations tab T prevent a specific simulation from being performed edit the file and use a comment character an exclamation point to comment out the line When the group of simulations is running the title bar of EP Launch will show the progress History of Simulations Performed The History tab allows you to see what files were associated with a particular simulation that was performed The list shows the date and time of the simulation along with the input and weather file names 17 RUNNING ENERGYPLUS EP LAUNCH PROGRAM lola File Edit View Help Single Simulation Group of Simulations History 2004 4u9 02 13 59 28 AZone irCooled idf 52one irCooled_1 2004 4u9 02 13 59 46 5Zone irCooled idf USA_CO_Boulder_TMY2 epw 52one irCooled_1 2004 4u9 02 13 59 56 5Zone uto idf 5Zone uto_1 2004 Aug 02 14 19 50 1ZoneUncontrolled idf 1Zonelincontrolled_1 2004 4ug 02 14 19 55 3zvent idf 3zvent_1 2004 4ug 02 14 20 17 3zwent idf USA_CA San Francisco_TMY2 epw USA_CA San 2004 4ug 02 14 20 43 3zwent idf USA _CO_ Boulder TMY2 epw 3zvent_1 2004 4u9 02 14 20 53 5Zone irCooled idf 52one irCooled_1 2004 4u9 02 14 21 12 5Zone irCooled idf USA_
79. s interact and interrelate Included here is the description of weather data used in EnergyPlus Output Details Examples and Data Sets while the Input and Output Reference document touch on some of the possible outputs from EnergyPlus this document has more details and specific examples It also addresses the example files that are distributed with EnergyPlus as well as the reference data sets that are included Auxiliary Programs This document contains information for some of the auxiliary programs that are part of the EnergyPlus package For example this document contains the user manual for the Weather Converter program descriptions on using Ground Heat Transfer auxiliary programs with EnergyPlus HVAC Templates and other assorted documents Engineering Reference Document 4 22 05 This document provides more in depth knowledge into the theoretical basis behind the various calculations contained in the program This reference includes more information on modeling equations limitations literature references etc The document contains the following information and is structured along the lines of the above illustration Figure 2 EnergyPlus Internal elements Heat Balance Overview and Reference This section describes the heat balance calculations that form the basis of the EnergyPlus building model It includes descriptions of shadowing calculations and other pieces of the model HVAC Overview and Reference This section contain
80. sfer InternalMass Areas internal to a zone Surface Shading Detached Shading devices external to the building face other buildings trees etc Surface Shading Attached Shading devices attached to the building overhang fin The pieces of the definition that designate Surface HeatTransfer surfaces as either heat transfer or heat storage surfaces are A5 A6 note type choice key Exterio key Ground field OutsideFace key OtherZone rEnvironment object 1list object 1list LALALA key OtherSideCoeff field OutsideFacel type object 1list ZoneNames OSCNames Xnote If OtherZone Xnote If OtherSideCoeff A7 A8 type choice key NoSun type choice LALALA key NoWind Environment Environment Object Used only if OutsideFaceEnvironment is OtherZone or OtherSideCoeff specify name of corresponding surface in adjacent zone key SunExposed field Sun Exposure ield Wind Exposure key WindExposed specify name of OtherSideCoefficients Note that subsurfaces windows doors on these base surfaces will inherit the base surface properties listed above The following examples will use a bit more of the Surface definition to give context Surfaces that specify themselves as the exterior environment are ceilings floors and partitions that divide temperature controlled spaces The program assumes that the sur
81. tains data sets of the following formats Table 8 Formats of weather data on the web site Data Number of Format Sites And by locations the following demographics are observed Table 9 General Locations of Weather Sites on web page Location Number of sites International 564 Canada 55 US 295 including 16 CTZ The US sites include the 16 sites for California Climates used in compliance for California Energy Codes CTZ A total of 914 weather files 100 countries represented 46 POSTPROCESSING READVARSESO PostProcessing ReadVarsESO The postprocessing program that is installed ReadVarESO is a simple program that reads the eplusout eso or eplusout mtr output files and produces a simple comma separated format that is easily accepted by a spreadsheet program such as Excel ReadVarsESO exe eplusout inp If you do not specify a file of input commands ReadVarsESO will produce its output file using all the variables available on the eplusout eso file PostProcessing Files details The following files are used or produced by this postprocessor eplusout inp This is an ascii text file read by RunReadESO bat The first line contains the name of the ESO file that the postprocessor will read The second line contains the name of the Excel compatible output file that it will write The subsequent lines specify which variables data will be extracted from the ESO file The variables may be specified b
82. tandard SI units IP Units for use by input processors with IP units Minimum that includes the following value Minimum that must be gt than the following value Maximum that includes the following value Maximum that must be lt than the following value Default for the field if N A then omit entire line Type of data for the field integer real alpha arbitrary string choice alpha with specific list of choices see object list link to a list of objects defined elsewhere see object list and reference Possible value for type choice blanks are significant use multiple key lines to indicate all valid choices Name of a list of object names that are valid entries for this fiela used vith Vrererence see ZONE and Surface HeatTransfer objects below for Name of a list of object names to which this object belongs used with type object list and with object list see ZONE and Surface HeatTransfer objects below for ZONE Al field Zone Name type alpha Xreference ZoneNames Surface HeatTransfer A4 field InsideFaceEnvironment note Zone the surface is a part of type object list object list ZoneNames For each zone the field Zone Name may be referenced by other objects such as Surface HeatTransfer so it is with reference ZoneNames 37 CREATING INPUT FILES STANDARD ENERGYPLUS UNITS Standard EnergyPlus Units EnergyPlus has adopted the st
83. the building model must 1 Determine heat transfer and heat storage surfaces 2 Define equivalent surfaces 3 Specify surfaces and subsurfaces windows doors etc construction and materials 4 Compile surface and subsurface information At this point it is appropriate to begin to introduce the structure of the input file Using the existing BLAST model we have constructed the EnergyPlus input file by using the BLASTTranslator program The single zone model as described later in this section will be included in the ExampleFiles when you install EnergyPlus This file can be used as described in other parts of this document to perform the building analysis Step3 1 Determine heat transfer and heat storage surfaces The surfaces of the building can be described in any order grouping surfaces by zone may help you read the input file Specifics of the describing surfaces help categorize the surface s heat transfer storage as well as identify the surface construction information The details of inputting surfaces are described in the Input Output Reference document The allowable surface types are shown in the following table 27 INFORMATION NECESSARY TO RUN ENERGYPLUS A METHODOLOGY FOR USING ENERGYPLUS 4 22 05 Table 3 Surface types and categorization Surface Type Applicability Surface HeatTransfer Wall Roof Ceiling Floor Surface HeatTransfer Sub Window Door Glassdoor Surface HeatTran
84. the zone Thus if a partition is completely within a zone both sides of the partition are exposed to the zone the area of each side must be added to the area of the equivalent surface On the other hand if the partition separates two zones the area of only one side should be added to the equivalent surface 3 Combine all windows on a given exterior surface into a single window Usually each exterior surface should have only one window of each type Overhangs or other shading devices may require that more windows be specified or combined together By using the WindowGlass construction for your glass door they will be correctly modeled in EnergyPlus with sunlight transferring into the zone The following figure shows the surfaces and subsurfaces required for a one zone model i e the Fort Monmouth education center Since there were two types of partitions in the building two heat storage surfaces internal mass of different constructions were defined 30 INFORMATION NECESSARY TO RUN ENERGYPLUS A METHODOLOGY FOR USING ENERGYPLUS 4 22 05 Internal Mass Const 3 Internal Mass 7 Const 2 Figure 8 Simplifications Using Equivalent Surfaces Step3 3 Specify construction elements BLAST DOE 2 and other programs often have libraries of constructions schedules and other aspects of simulating the building Since EnergyPlus has been designed as an engine we are relying on EnergyPlus Inte
85. ting Input Files The following steps have been liberally lifted and changed from the BLAST Building Loads Analysis and System Thermodynamics User s Manual Please excuse any inaccuracies in the translation from BLAST these are meant as general guidelines A Methodology for Using Energyplus 4 22 05 This section provides a step by step outline that will help you streamline creating your building models for using EnergyPlus Step 1 Plan Ahead Some preliminary steps will facilitate the construction of your input file EnergyPlus requires some information in specified externally available formats other information may require some lead time to obtain The following checklist should be completed before you start to construct your input file V Obtain location and design climate information for the city in which your building is located If possible use one of the weather files available for your weather period run V Obtain sufficient building construction information to allow specification of overall building geometry and surface constructions including exterior walls interior walls partitions floors ceilings roofs windows and doors V Obtain sufficient building use information to allow specification of the lighting and other equipment e g electric gas etc and the number of people in each area of the building V Obtain sufficient building thermostatic control information to allow specification of the temperature contr
86. tion desorption either as a layer by layer integration into the conduction transfer functions or as an effective moisture penetration depth model EMPD gt Thermal comfort models based on activity inside dry bulb humidity etc ENERGYPLUS OVERVIEW WHY DOES ENERGYPLUS EXIST AND WHAT WERE ITS ORIGINAL GOALS gt Anisotropic sky model for improved calculation of diffuse solar on tilted surfaces gt Advanced fenestration calculations including controllable window blinds electrochromic glazings layer by layer heat balances that allow proper assignment of solar energy absorbed by window panes and a performance library for numerous commercially available windows gt Daylighting controls including interior illuminance calculations glare simulation and control luminaire controls and the effect of reduced artificial lighting on heating and cooling gt Loop based configurable HVAC systems conventional and radiant that allow users to model typical systems and slightly modified systems without recompiling the program source code gt Atmospheric pollution calculations that predict CO2 SO NO CO particulate matter and hydrocarbon production for both on site and remote energy conversion gt Links to other popular simulation environments such as WINDOW5 COMIS airflow model and SPARK to allow more detailed analysis of building components More details on each of these features can be found in the various parts of the EnergyPlus
87. tput files open a spreadsheet for the postprocessor results files a web browser for the tabular results file and start up a viewer for the selected drawing file RUNNING ENERGYPLUS EP LAUNCH PROGRAM lola File Edit View Help Single Simulation Group of Simulations History m Input File C EnergyPlus ExampleFiles 1ZoneU ncontrolled idf Browse Edit Text Editor Edit IDF Editor Weather File C EnergyPlus WeatherD ata USA_IL_Chicago OHare_TMY2 epw e Browse Wiew Results Text Output Files Drawing File i HTML Simulate EnerayPlus 1 1 1 008 Exit Figure 3 EP Launch Screen Start EP Launch EP Launch should be located in the directory that you installed EnergyPlus By double clicking on the EP Launch icon you get the screen shown above Figure 1 for running a single simulation The EP Launch program simply starts other programs and allows you to avoid having to use the DOS command line prompt to run EnergyPlus More help is provided for the program under the Help menu Selecting Input and Weather Files The input file and weather files can be selected on the Single Simulation tab from the two pull down lists which show recently used files or you can press the Browse buttons to locate an input or weather file that you have created yourself Running a Single Simulation On the Single Simulation tab after you select the weather
88. unch If EP Launch seems to be starting slowly it is possible that the history file has grown very large lt may be deleted or renamed and a new history file will be automatically created during the next simulation The HISTORY CSV file may also be opened in a spreadsheet program Caveats Remember to save changes made in the editor before you run another simulation The simulation cannot write new results to open files which are locked by another application You will need to close the spreadsheet program that views the resulting CSV files prior to another simulation and you may need to close the text editor windows also depending on your editor The EPL RUN BAT batch file is used to run EnergyPlus from the EP Launch program It can be edited with care if other postprocessors or preprocessors are to be used 4 22 05 18 RUNNING ENERGYPLUS EP LAUNCH PROGRAM 4 22 05 When things go wrong Though EnergyPlus has had several releases including beta releases prior to initial release there still may be problems when input files meet with EnergyPlus If you are using EP Launch when this happens you will see a window appear as in the figure below Figure 10 Follow the instructions listed on the screen Q EnergyPlus Crashed O Please Report Crash Send the active EnergyPlus input file named D Testing 52ZoneAirCooled idf with a description of any recent changes to energyplus support gard com Indicate in your e mail that you we
89. vi may be opened in the text editor View Menu The View menu Figure 3 duplicates the options in the View Results area of the main screen see the Looking at the Results section above and allows opening of selected output files In addition you can turn on and off the Pause During Simulation feature described in the Running a Single Simulation section above select a wide format useful for long path names or select an alternative interface with a different arrangement of buttons ala File Edit view Help e Text Output Files i Drawing File Spreadsheets HTML File Group File Bro Selected History File Edit Text Editor Edit a IDF Editor ERR EIO BND Output Files Only EE Weath Single File gt CAEn Pause During Simulation Tab Delimited Open With Spreadsheet Allow gt 250 Columns View R Wide Alternative Interface Simulate EnerayPlus 1 1 1 008 Figure 3 EP Launch View Menu Comma separated variable CSV is the default setting for viewing tabulated results set in the RVI file If the user changes the setting for viewing tabulated results to TAB or TXT format selecting Single File and then Main Results File from the View menu or pressing the F4 function key will open the files in the default text editor TAB files when selected will also 4 22 05 13 RUNNING ENERGYPLUS EP LAUNCH PROGRAM be opened by the text editor
90. when the Text Output Files button is pressed after a successful run Selecting HTML File from the View menu will open any user created files saved in the format lt filename gt table html see Report Table Style If the Tab Delimited Open With Spreadsheet is elected from the View menu selecting Single File and then Main Results File from the View menu or pressing the F4 function key will open TAB files with the default spreadsheet application rather than the text editor Tabulated data that exceeds 250 columns the MS Excel maximum will be truncated to that limit unless Allow gt 250 Columns is selected from the View menu Help Menu The Help menu can be used to open the EnergyPlus documentation files and the EP Launch help file Recently Used Files The recently used input weather and group file pull down lists can hold a maximum of twenty items These lists like the viewers selected are saved between times you use the EP Launch program Running Groups of Simulations If you are running EnergyPlus on one file or even just a few different files the easiest way to do this is on the Single Simulation tab If you are performing an analysis of a building which requires running EnergyPlus for a larger number of times you may want to consider the Group of Simulations tab shown below lx File Edit View Help Single Simulation i El History m Group File New G
91. xplanation of Keyword portion of the screen 3 The value can be edited Depending on the field a drop down list may display the default value maximum and minimum or other keywords that can be used with the field 4 Numeric fields that can be autosized will include autosize as a selection in the drop down list 5 Some numeric fields have a maximum and or minimum value specified in the IDD If the value entered is outside this range the cell will be highlighted in pale orange Working with Objects To delete an object first click on any value for the object and then click on the Del Obj button To add a new object click on the New Obj button and a new object column with fields set to blanks or zeros will be added to the far right of the grid The Dup Obj button is similar to New Obj but copies the values of the fields of the currently selected object Also see the Edit menu to perform these functions File Menu The File menu can be used for creating or selecting input files just like the buttons on the IDF Editor screen see the Creating or Selecting an Input File section above In addition the File menu is used to save a file or exit the IDF Editor More than one file can be opened at a time Edit Menu The Edit Menu offers options to create a new object duplicate an object and delete an object These same operations can also be accomplished by using the New Obj Dup Obj and Del Ob
92. y unique number or by name one variable per line You can also choose to not report a variable by putting a tilde in front of the report variable name The file is terminated with a line containing 0 An example of eplusout inp is eplusout eso eplusout csv Outdoor Dry Bulb PSI FOYER Mean Air Temperature DORM ROOMS AND COMMON AREAS Mean Air Temperature LEFT FORK Mean Air Temperature MIDDLE FORK Mean Air Temperature RIGHT FORK Mean Air Temperature PSI FOYER Zone Total Electric Consumption DORM ROOMS AND COMMON AREAS Zone Total Electric Consumption LEFT FORK Zone Total Electric Consumption MIDDLE FORK Zone Total Electric Consumption RIGHT FORK Zone Total Electric Consumption 0 eplusout eso This is the standard output file from EnergyPlus The above example is an illustration of use for the ESO from the GeometryTest example input file The data dictionary section of the GeometryTest ESO file looks like 6 2 Environment Outdoor Dry Bulb C Hourly 21 2 PSI FOYER Mean Air Temperature C Hourly 22 2 PSI FOYER Zone Total Latent Gain J Hourly 26 2 PSI FOYER Zone Total Electric Consumption J Hourly 27 2 DORM ROOMS AND COMMON AREAS Mean Air Temperature C Hourly 28 2 DORM ROOMS AND COMMON AREAS Zone Total Latent Gain J Hourly 32 2 DORM ROOMS AND COMMON AREAS Zone Total Electric Consumption J Hourly 33 2 LEF FORK Mean

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