DOE-2 Reference Manual Version 2.1 - DOE2.com

Only one configuration of building and equipment can be evaluated by thePLANT program in a single run. The costs calculated for this configurationare passed to the ECONOMICS program, where the user enters the additional costdata necessary to perform tradeoff studies. If a comparison between theproject and a baseline (i.e., the existing building or an alternative designconcept) is being made, cost data on the baseline must be entered. These costdata can be obtained from the PLANT economics output reports of a separate runsimulating the baseline conditions. They must be entered with the ECONOMICSprogram input for each alternative studied.3. Suggested Procedure for Use of the PLANT ProgramThe PLANT_ program can be used to obtain improved design configurationsfor total energy plants, conventional energy plants, and selective energyplants (hybrid combinations of the first two). The effective use of theprogram depends upon an understanding of the problem. Because the executiontime of PLANT is small, parametric studies to determine "optimal" or nearoptimal configuration are relatively inexpensive. The user can make a numberof PLANT runs, each simulating equipment type and/or size variations, and canuse the output reports to zero-in on the preferred arrangement. SYSTEMSprogram output files from the initial run should be saved to avoid the cost ofrerunning that program (and the LOADS program) for each PLANT run. See thelocal site manual for the method of saving these files.Users will undoubtedly develop their own methods of using PLANTeffectively. The following summarizes one method for using the PLANT program.a. Run the LOADS and SYSTEMS programs to produce the hourly energyextraction rates. As indicated above, save the SYSTEMS output filefor use in the PLANT program runs.b. Identify all physical and environmental constraints and list themto eliminate impractical configurations (for example, dieselengines may be unacceptable on the top floor of a hospital becauseof noise level).c. Identify types of equipment under consideration and their availablesizes. On the basis of the results of items a. and b., estimatemaximum loads as a guide to choosing equipment for the initial testrun.d. Identify all known applicable quantities for the proposedinstallation, and prepare input data to override default values.For example, if the boiler operates by schedule, running in astandby mode when the schedule is "on", even if there is no load,BOILER-CONTROL should be set to STANDBY in the PLANT-PARAMETERSinstruction. If no actual values for data items are known, noentry is necessary; default values will be supplied by the program.e. If a specific brand of equipment is under consideration, compareits performance coefficients with the model in the program. Ifthey differ significantly, use the PART-LOAD-RATIO andPLANT-PARAMETERS, and then, if necessary, the EQUIPMENT-QUAD andCURVE-FIT instructions to override built-in default values.V.3 (Revised 5/81)