Multifamily energy-efficiency retrofit programs: a Florida case study
Multifamily buildings are an important target for efficiency improvements because of their energy savings potential and housing market share. Yet few multifamily retrofit projects have been completed in hot-humid regions and even fewer studies have measured and verified savings from such projects. Addressing this gap, the purpose of our research is to assess the impacts of energy-efficiency upgrades to multifamily buildings in Orlando, FL. Specifically, we measure the first-year electricity savings from retrofits to 232 units in four apartment complexes. Annual savings per unit averaged 2094 kWh (22 %) and ranged from 1700 kWh (18 %) to 3811 kWh (29 %) across complexes. Monthly savings ranged from 48 kWh (9.4 %) in December to 340 kWh (31 %) in August. From these core findings, we estimate that tenants in treatment units saved an average of $272 on their electric bills. We also find evidence to support a strategy of targeting upgrades to improve overall savings and program cost-effectiveness. Results are being used to guide development of a utility demand-side management program for multifamily property owners. Progress in this market requires additional pilot projects, access to utility data, reliable measurement and verification of savings, and innovative financing structures.
KeywordsEnergy efficiency Demand-side management (DSM) Multifamily buildings Residential retrofits Impact assessment Electricity savings Measurement and verification (M&V) Project case study Hot-humid climate High-efficiency HVAC
The retrofit project described in this article was paid for, in part, by a grant from the Florida Energy and Climate Commission with funding from the United States Department of Energy (EE0000241), through the American Recovery and Reinvestment Act, and by the Orlando Utilities Commission. The research was sponsored, in part, by the Orlando Utilities Commission and by the John D. and Catherine T. MacArthur Foundation. The authors would like to acknowledge the work of Tom Gross and Cameron Saulsby, of the Orlando Utilities Commission, in collecting and providing detailed data from the apartment retrofits described in this article. We would also like to thank our colleagues Lynn Jarrett and Hal Knowles for their support in this work.
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