Demand Response with Pre-Cooling Study of a Small Commercial Building with Thermal Mass in California

Previous field studies demonstrated the effectiveness of demand response (DR) control strategies to reduce the peak demand in large commercial buildings by utilizing the building thermal mass. Meanwhile, the occupancy surveys were conducted to evaluate the impact of various control strategies on the occupancy comfort. However, these field tests were conducted mostly in large commercial buildings with consistent occupancy behavior. This project provided an opportunity to evaluate the effect of pre-cooling with zone temperature reset strategies to reduce peak demand in a small retail building in warm California climate. The customer comfort surveys were conducted to demonstrate the impact of DR strategies and unique occupancy behavior (short staying time, active state…) on occupancy comfort. Even though the 1-degree F granularity zone temperature setpoints limited the implementation of the exponential temperature setup, the “pre-cooling with step temperature reset” strategy worked well in the field tests. The test results show that the electricity demand during the peak period can be reduced, on average, as much as 44% of whole building power. However, the demand ramp at the beginning of the peak period weakens the effect of DR strategies for reducing the peak demand through the whole peak period. On the occupancy comfort side, based on the results from the comfort survey, the store is normally maintained between 70-72.5°F (21-22.5ºC), and 78% of its patrons feel comfortable