DOE-2 Reference Manual Version 2.1 - DOE2.com

V. PLANT EQUIPMENT SIMULATION PROGRAMA. INTRODUCTION1. Program DescriptionThe PLANT program simulates the primary equipment that uses energy (e.g.,oil, gas, electricity, or sunshine) to provide heating and cooling. Plantequipment may include on-site electric generating and heat recovery capabilitiesthat meet the coincident electrical, heating, and cooling demands of thebuilding. Conventional central plant equipment (e.g., boilers, chillers) orselective energy plants (a hybrid configuration having utility electricity,steam, or chilled water and on-site electric generation capability) can besimulated using this program.The PLANT program receives, as input, a list of the hourly loads for thebuilding from the SYSTEMS program, and requires a sequence of user-defined POLinput instructions that specify the plant. Each instruction (or class of data)has its own POL command word for identification and a keyword for each item ofinformation.The program can be run with minimal specification of plant equipment,consisting only of the type and size of equipment, the total number ofinstalled units, and the maximum number of units simultaneously available.no other data are entered, the preprogrammed default value will be used foreach variable.The program uses the hourly demands and other hourly information, receivedfrom the SYSTEMS program, to calculate the energy consumption of the specifiedequipment on an hourly basis and summarize it by month and by year. The inputdata to the PLANT program from the SYSTEMS program consist of the following:Heating load, cooling load, electric load, process heat or domestic hotwater load, baseboard load, gas and oil consumption from SYSTEMS andLOADS, ambient air and wet-bulb temperatures (for simulation of chillers,cooling towers, generating equipment, etc.), heating and coolingequipment on-off flags in SYSTEMS.Preheat load, main coil load, zone-coil load; outside air cfm, main coilcfm, and system cfm; main coil or cooling coil discharge temperature andthe mixed air temperature (for solar simulation).Energy use is simulated on the basis of a full load input/output ratioand/or a representative quadratic curve fit of part-load performance for·eachclass of equipment. The default values for these parameters are shown inTables V.4 and V.6 in Sec. B of this chapter. Some typical curves are shownand discussed in the DOE-2 Engineers Manual. The user should examine thedefault values carefully before accepting them. If values can be obtainedthat more accurately represent the performance of a particular item of equipment,they should be entered, using the CURVE-FIT, EQUIPMENT-QUAD, and/orPART-LOAD-RATIO instructions.Additional information required for simulation of energy use is providedby the PLANT-PARAMETERS instruction. For example, keywords HCIRC-MOTOR-EFF,CCIRC-MOTOR-EFF, and TWR-MOTOR-EFF define, in that order, the motor efficiencyV.l (Revised 5/81)If