Walmart announce to install up to 400 new solar projects at facilities across the nation over the next four years. This represents the company’s commitment to drive the production or procurement of seven billion kWh of renewable energy by the end of 2020 and its goal to be supplied by 100% renewable energy. To facilitate these installations, Walmart selected proposals from SolarCity and SunEdison following an RFP process.

Working with numerous solar providers, Walmart has installed approximately 260 solar projects, totaling 105MW, to date in the United States. This has saved more than US$5 million in energy expenses.

“This is the beginning of the next wave in renewable energy for Walmart, an effort we announced in May when we welcomed President Obama to our Mountain View California store,” said Kim Saylors-Laster, vice president of energy at Walmart. “These projects bring us closer to fulfilling our commitment to double the number of on-site solar energy projects in U.S. stores, Sam’s Clubs and distribution centers—thereby reducing our energy expenses and generating clean energy in local communities.”

The installations will vary in size, commensurate with the respective store or facility. It is expected that smaller systems will provide 10 to 20% of the facility’s electricity requirements and larger systems will provide 20 to 30% of the power needed by the facility.

“SunEdison is one of Walmart’s earliest solar providers with projects dating back to 2007,” said Katherine Jennrich, senior manager of energy services at Walmart. “And, SolarCity has been Walmart’s largest solar provider, installing more than 200 projects together since 2010. We are excited to expand our work with both providers.”

According to the contract signed by SolarCity and Walmart, SolarCity will not only install solar systems for Walmart in up to 36 states in the following four years, but also provide additional battery storage projects. Since 2013, Walmart has tested 13 battery storage projects with solar installations across California. The next 10 solar energy storage projects will each use a larger 200kW (400 kWh) battery to expand storage capabilities.