GW will start deriving more than half its electricity from solar energy this winter after the creation of a renewable energy project in North Carolina.

GW Hospital and American University will also buy energy from the solar power farms, officials announced Tuesday. Those farms will power the largest photovoltaic project – in which light creates an energy current – east of the Mississippi River.

The three institutions announced a 20-year contract with the energy company Duke Energy Renewables on Tuesday, which University President Steven Knapp said will help GW reach its long-term energy goals without piling on costs.

The three partners will start building the solar panel farms this summer, and will receive energy from the locations by the end of the year. The farms, which will include 243,000 solar panels, will be fully functional by the end of 2015.

“We’re not just buying certificates for renewable energy. We’re actually directly sourcing from renewable energy. The impact of that is pretty huge,” Knapp told the Associated Press. He added that building the farms will not require any start-up capital costs.

The partners selected the North Carolina-based company through a bidding process with 28 wind and solar companies.

When the project is complete, GW will receive about 86.6 million kilowatt hours from the farms, and GW Hospital will derive more than one-third of its energy from them. The solar power generated from the panels will move from a North Carolina power grid to a D.C. regional grid for both universities.

The partners expect the project to produce the same effects as taking 12,500 cars off the road.

“Joining this partnership to embrace alternative power reflects our daily work as health advocates — caring, healing, teaching and birthing new generations,” said Barry Wolfman, chief executive officer and acting managing director of GW Hospital, in a release.

Over the next 20 years, GW, American University and GW Hospital will pay a fixed rate for the solar energy – an agreement their leaders say will save money as electricity prices are expected to rise in that time.

GW’s Office of Sustainability has planned out ways for the University to shrink its ecological footprint by 2020, such as aiming to become a zero-waste college and setting up gardens across campus. The University also recently built a solar-powered walkway on the Virginia Science and Technology Campus.

This post was updated to reflect the following correction:
The Hatchet incorrectly reported that the solar walkway on the Virginia Science and Technology Campus connects two buildings. Exploration and Innovation Halls are connected by a sidewalk that has a solar trellis. We regret this error.