Computer Simulation Appraisal of Low Energy Cooling System Configurations

Goal Statement:
To evaluate the applicability, potential energy savings, and demand reductions of different types of low-energy cooling systems in California.

Results:
A comprehensive parametric computer simulation, using DOE2.1E W110, was completed for the following systems:

• Indirect/Direct Evaporative Cooling
• Water-Side Free Cooling
• Chilled Beams
• Displacement Ventilation (approximate models)

The systems were simulated in a generic commercial building model using the following input variations to approximate a range of commercial building types:

• Minimum Outside Air & 12-hour occupancy
• 100% Outside Air & 12-hour occupancy
• Minimum Outside Air & 24-hour occupancy
• 100% Outside Air & 24-hour occupancy

For each of the four model inputs, the following parameters were then specified: system type, climate zone, envelope performance, and thermal mass exposure. The input combinations were simulated, and results were output to spreadsheet tables. The system performance was evaluated in terms of energy use, peak electricity demand, and the number of hours that the system is not able to maintain space temperatures within the thermostat throttling range.

The DOE2.1E results were published and presented in the 2002 American Council for an Energy-Efficient Economy (ACEEE) Summer Study Proceedings.

DOE2.1E Phase I Simulation details.

Downloads and Links:

• "A Computer Simulation Appraisal of Non-Residential Low Energy Cooling Systems in California", Bourassa, N., P. Haves and J. Huang, Lawrence Berkeley National Laboratory. Published in the 2002 ACEEE Summer Study Proceedings. (1.58 MB, 13 pp)

Contact: Philip Haves, Lawrence Berkeley National Laboratory (LBNL), (510) 486-6512