Apartment building residents and owners in the U.S. could save nearly $3.4 billion annually by implementing energy efficiency upgrades, according to a new report from CNT Energy and the American Council for an Energy-Efficient Economy.

The report, Engaging as Partners in Energy Efficiency: Multifamily Housing and Utilities, indicates that upgrades can generate energy cost savings of 15% to 30% in buildings with five or more residential units. The report also found that energy utilities play a critical role in unlocking these savings through the use of rebate programs and other financial incentives. Utilities’ contributions to energy efficiency programs are expected to increase from $4.3 billion in 2009 to as much as $12 billion annually by 2020. (more…)