Two Cummings Properties buildings, 18 Commerce Way in Woburn and 500 Cummings Center in Beverly, have earned the U.S. Environmental Protection Agency’s Energy Star certification.

Built in 2004, 500 Cummings Center’s original design included a number of green features, including high-efficiency lighting and water source heat pumps, as well as motion sensors and variable frequency drives, according to a statement.

Built in 1996, 18 Commerce Way underwent a comprehensive, three-year energy-efficiency upgrade in preparation for its Energy Star evaluation. The modifications included changing all 850 lights in the building to high-efficiency fixtures; installing variable-frequency drives on the loop pumps and cooling tower fan; upgrading the cooling tower fan to high efficiency; installing motion sensors in the hallways; and installing a vending miser on the vending machine.

"Cummings has a longstanding commitment to energy efficiency," said Gary Gresh, Cummings Properties’ sustainability manager. "In addition to being the right thing to do for the environment, our clients save on operating costs, which helps us attract more client firms. Everyone wins."

Cummings now has seven properties with Energy Star certifications, according to a statement.