A Case Study in Reconciling Modeling Projections with Actual Usage

摘要

A subdivision, built near Sacramento, CA was designed to incorporate advancedresidential energy efficiency strategies as part of Department of Energy’s (DOE) BuildingAmerica (BA) program. Energy efficiency measures included attic radiant barrier, condensingfurnace, high efficiency air conditioning, tankless gas water heater, efficient lighting, and thirdparty building inspections. Detailed DOE-2 building simulation was used to project energyperformance and utility bills. Analyzing one year of billing data obtained from these homes aswell as 100 surrounding reference homes suggest that even when detailed data is known, energysimulation is not effective in characterizing energy by end use. Results show natural gas use onaverage was 36% lower than simulated projections and supports a study done on Californiacompliance software model projections (KEMA et al. 2010). Electrical use patterns on the otherhand varied from model projections inconsistently, due in part to anomalies not accounted for inthe model. Results indicate that household variations in energy usage patterns and appliancepenetration rates have a very strong effect on total energy use. This issue seems especiallypronounced in mild climate regions of the country where miscellaneous plug loads, lighting, andlarge appliances can exceed 80% of the total electric use. Understanding and influencinghomeowner behavioral patterns is important in delivering high performing homes to the market.Additional research into the effectiveness of energy control mechanisms, such as motiondetecting lighting, phantom load controls, home energy displays, and educational programs arerequired in order to incorporate these savings into building simulations.