The simulation process fits into the energy calculation sequence as shown in Fig 1. The heating-and cooling-load section of the energy calculation determines the sensible and latent gains or losses for each space hour-by-hour. The simulation process receives this information and translates the instantaneous heating and cooling loads of all spaces in the building into the energy requirement of the heating and cooling plant(s). The simulation section feeds its information to the economic section where the energy quantities and costs are totaled. The calculation sequence then returns to the weather data for the next hour and repeats the cycle.

The work of the ASHRAE Task Group on Energy Requirements for Buildings was subdivided into several sections, and it was the responsibility of the Subcommittee on Systems and Equipment to develop a booklet that provided guidelines for the simulation of components and systems for energy calculations. The final version of this booklet is the third edition of the document and represents expansion and refinement of the preceding editions. The purposes of the simulation booklet are (1) to provide a guide to those preparing energy calculation programs and (2) to aid in standardizing procedures and equations representing component and systems performance.

The function of this symposium paper is topresent an overview of the simulation booklet so that the reader could better decide whether to dig deeper into the details included in the booklet. The two main sections of the booklet are (1) Component Simulation and (2) System Simulation. These sections will be reviewed in Parts I and II. respectively, of this symposium paper.