The District will soon install solar panels on the roofs and parking lots of 34 government-owned facilities, bumping the city government’s total solar energy capacity by about 70 percent, according to an announcement from Mayor Muriel Bowser this week.

Bowser hailed the project as one of the largest municipal onsite solar projects in the United States. The D.C. Department of General Services struck the agreement last week to purchase the power — known as a Power Purchase Agreement — with Nextility Inc., a D.C.-based energy company.

Officials estimate that it will save taxpayers $25 million over the deal’s 20-year term.

DGS has been working on a Purchase Power Agreement for about two years, according to an agency spokesman, starting when Mayor Vincent C. Gray (D) was still in office. It took effect immediately.

“Beyond renewable energy and cost savings, this project will elevate the District’s local economy, spur small business development and spur jobs,” Bowser said in a statement.

In August, the city signed a deal with a Spanish-energy company that provided city facilities with 125,000 megawatt hours of electricity annually from a wind power farm in Pennsylvania. That deal meant the local government could meet about a third of its energy needs from wind power, saving the city government about $45 million on its energy bills over 20 years.

With this latest deal, the city says 40 percent of its energy needs will be fulfilled through solar or wind energy.  For city-owned buildings that have these solar energy systems installed on site, 20 percent of electricity consumption will be met by solar energy.

For commercial properties, the city signed a deal that would allow the city to help businesses finance energy upgrades through property tax bills.

“DGS will pay a contractually-established unit rate per kilowatt hour of electricity generated by the systems for 20 years,” said Mark Chambers, director of sustainability and energy at DGS.

DGS said the solar energy systems will be installed throughout 2016. The construction and design process will create 140 jobs, including five permanent jobs for ongoing operation and maintenance of the system.

This latest energy announcement comes two months after Bowser decided to reverse course and back the controversial Pepco-Exelon merger, which environmentalists have largely opposed. In November, environmentalists and good government groups called for an ethics investigation into why Bowser changed her mind, alleging that it may be connected to an agreement between Bowser’s administration and Pepco for $25 million to offset city costs to build a new stadium for the city’s Major League Soccer team, D.C. United.

Bowser has long insisted that her change of  heart had to do with the companies’ agreeing to make a greater investment into the city, including more money going toward conserving natural resources and sustainability.