Multifamily Retrofit Data Show Real Savings
An analysis of pre- and post-retrofit data on energy costs for multifamily properties demonstrates substantial savings. The study, conducted by Bright Power and Stewards of Affordable Housing for the Future, analyzed data from 179 properties in HUD’s Green Retrofit Program (GRP) and 57 properties in Illinois’s Energy Savers program. The initial data set included more than 13,000 separate utility accounts and more than 3,000 energy and water retrofits. Due to substantial differences in the properties and programs, each data set was analyzed separately.
- Through energy and water retrofits, properties in HUD’s Green Retrofit Program reduced energy consumption by 18% and water consumption by 26% for a total portfolio savings of approximately $4.3 million per year.
- GRP properties achieved an average savings per unit of $213/year for energy and $95/year for water.
- Properties in Illinois’s Energy Savers program reduced gas consumption by 26% (or $195 per unit per year) for an annual portfolio savings of $381,000.
- The post-retrofit savings were higher for properties with more energy or water use per square foot, also known as energy or water “use intensity.” Savings vary greatly across properties.
- Water saving retrofits had a one-year payback period and a savings-to-investment ratio of 9, based on marginal costs. Savings far surpassed costs.
- Energy saving retrofits in GRP properties had an estimated 15-year payback period and a savings-to-investment ratio of 1.2, based on marginal costs. Lifetime savings exceeded costs by 20%.
- Gas savings for Energy Savers properties had a 7.3-year payback period and a savings-to-investment ratio of 2.8, using full rather than marginal costs.