Impact evaluation of a major residential efficiency program: The importance of market transformation

In the Pacific Northwest, about 40% of new electrically heated homes are HUD-code manufactured homes (commonly called {open_quotes}mobile homes{close_quotes}). The U.S. Department of Housing and Urban Development (HUD) sets national energy-efficiency construction standards for manufactured homes that preempt them from local building codes. Until October 1994, a relatively low efficiency requirement established in 1976 by HUD was in place for manufactured homes. The Bonneville Power Administration (Bonneville) is required to acquire cost-effective energy efficiency to meet the electricity needs of the Pacific Northwest. Because electrically heated manufactured homes are so common and are relatively inefficient, Bonneville, utilities, state energy offices, and others have conducted a series of programs since 1982 to upgrade their efficiency (1). Because of the preemptive national code, these programs have all been voluntary for manufactured homes. Bonneville and the regional utilities and manufacturers created the Manufactured Housing Acquisition Program (MAP) in April 1992 after conducting projects for ten years to determine the cost of manufactured home energy-efficiency upgrades, predict and measure energy consumption, and establish a regional partnership. The program was phased in over several months; since October 1992, all electrically heated manufactured homes produced in the region have been built to MAP specifications.