Walgreens, the nation’s drugstore chain, together with Chicago-based solar developer SoCore Energy, said they will build more than 200 new solar installations at Walgreens drugstores throughout California, Connecticut, Delaware, Massachusetts, New Jersey and New York. This latest expansion will bring the number of completed solar installations at Walgreens stores to more than 350, making the company the leading retailer in number of solar powered stores.

The upcoming rollout will produce an estimated 13.5 million kilowatt hours annually, the equivalent of offsetting the CO2 emissions from the electricity use of more than 1,400 homes for one year. Included in the rollout is the Walgreens net-zero energy, LEED Platinum store in Evanston, Ill., which will feature more than 850 roof-top solar panels.

Walgreens will host the solar arrays, and SoCore Energy will own, operate, and maintain them. This model has proven to be successful for the two Illinois-based companies since 2011, when the two collaborated on a 53-store rollout across the state of Ohio.

This unprecedented rollout is the latest of many green initiatives for Walgreens. The company currently operates three stores that have achieved a LEED certification level of gold, silver and certified; a store in Oak Park, Ill., using geothermal energy; a distribution center in Waxahachie, Texas, that generates energy though the use of wind; and 400 locations with electric vehicle charging stations. Walgreens drugstores use 25 watt fluorescent lamps (lowest wattage in the industry), LED cooler and freezer lighting and energy management systems in more than 5,000 locations. In addition, 15 Walgreens distribution centers have achieved net zero waste, which means revenues from recycling exceed waste expense.

Through the U.S. Department of Energy’s Better Buildings Challenge, Walgreens has committed to a chainwide 20 percent energy reduction by 2020.