Thermal sensitivity of the commercial sector

We examined the thermal sensitivity of building total loads and heating, ventilating, and air-conditioning (HVAC) loads in all nine commercial building types. In groceries and restaurants, refrigeration loads were also studied. The data indicated that the thermal sensitivity of building total and HVAC loads is small for all types of buildings. We found the thermal sensitivity of refrigeration loads also to be small for groceries and restaurants. These findings led us to conclude that, although corrections for weather might improve forecasted loads, the improvement is probably too small to justify the effort required to do so. We next examined the effects of building size, age, and primary heating fuel on thermal sensitivity. We compared our results with common expectations that small buildings are more thermally sensitive than larger buildings, old buildings are more thermally sensitive than new buildings, and electrically-heated buildings are more thermally sensitive than those heated by other fuels. As expected, small buildings were found to be more sensitive to the weather because of the higher ratios of envelope area to conditioned volume. However, neither vintage nor fuel type was found to affect HVAC loads. We investigated the use of hearing and cooling degree-days calculated to a basemore » temperature of 65{degree}F as the basis for a weather-adjustment procedure. We concluded that a simple degree-day correlation is a promising prospect because it would be easy to develop and implement.« less