Modular HVAC Simulation and the Future Integration of Alternative Cooling Systems in a New Building Energy Simulation Program

The interest in both modular simulation and alternative cooling systems continues to rise both in the United States and in other countries, particularly those nations where concerns for climate and the global environment are high. Modular simulations allow program users to test out configurations that are different from the standard systems and may sometimes lead to innovative design solutions. At the same time, the U.S. Department of Energy has released its new building energy simulation program, EnergyPlus. Its integration of a modular HVAC simulation within the framework of a comprehensive building thermal simulation has resulted in a program with significant initial capabilities and flexibility. This relative flexibility in comparison with its parent programs and the feedback from the integrated building, system, and plant simulation modules allows users to investigate the use of nonstandard systems and will eventually allow the analysis of more complex alternative systems. This paper first provides an overview of the HVAC simulation method of the new program as background and then discusses some of the alternative cooling system models that are made possible by the simulation environment and will hopefully be implemented in a more integral way within the program in the near future.