As energy efficiency plays a growing role in real estate and mortgage credit, Freddie Mac decided to up the ante in its multifamily business and offer a $5,000 green rebate to borrowers. Qualified borrowers with at least 20 units who voluntarily provide an Energy Star score when submitting their loan documents, are eligible. Freddie said it hopes to encourage energy efficiency and affordability in apartment properties and strengthen the market for green investments. Freddie also said rental housing is home to many of the country’s lower-income households who are struggling with housing costs such as rent and utilities. The Environmental Protection Agency estimates that the average commercial building wastes 30 percent of the energy it consumes, often resulting in higher operating costs.