The Portland City Council voted unanimously Wednesday night to authorize an agreement to build one of the state’s largest municipal solar power arrays on the Ocean Avenue landfill.

The vote will allow City Manager Jon Jennings to negotiate an agreement with ReVision Energy LLC at a cost to the city of $150,000 over its first six years. The project would reduce the city’s reliance on fossil fuel-based electricity by 25 percent over the next decade, Mayor Ethan Strimling said.

“This is a great step in that direction,” he said.

Steve Hinchman, a spokesman for ReVision Energy, said the project will still require approval from the Maine Department of Environmental Protection once a contract has been finalized and ratified by the City Council. Hinchman said construction could begin in 60 days.

“All that’s left is the boilerplate language,” said Hinchman.

Several people in the audience who were wearing buttons supporting solar power applauded the council vote.

ReVision proposed the solar project in June 2015. Under ReVision’s proposal – the only one submitted to the city – the company agreed to install and own a 660 kilowatt array on the closed landfill, located near the Falmouth town line.

The project would require the city to invest about $25,000 per year for the first six years, after which the city would have the option of purchasing the array, according to Troy Moon, Portland’s Sustainability Coordinator.

Moon said the solar array would generate enough renewable energy to power City Hall and Merrill Auditorium, and is expected to save the city more than $3.2 million in energy costs over its lifetime.

In January 2016, the city of South Portland joined the venture and plans to have an identical solar array built on its closed landfill. Combining the two projects is expected to reduce overall project costs.

The Portland project would create one of the largest municipal solar arrays in Maine. The city’s Planning staff is currently revising zoning rules to allow stand-alone solar generation facilities in Portland. The Planning Board will hold a public hearing on the revisions later this year.

City officials expect the investment to be paid back in 10 years through energy savings.

“This proposal is a meaningful step in Portland’s commitment to a clean energy future,” Councilor Jon Hinck, chair of the council’s Energy and Sustainability Committee, said in a news release.

“The Ocean Avenue project will be a very visible demonstration of the city of Portland walking the walk and setting a powerful example when it comes to embracing solar technology,” Strimling said in the release.

“The Ocean Avenue solar project is a major step forward for the City of Portland’s commitment to clean renewable power. Sierra Club’s Portland Climate Action Team is proud to have played an important role in initiating and supporting this historic project, and we are looking forward to working with the City on a plan to dramatically scale up solar in Portland,” Sierra Club Maine Chapter Director Glen Brand said in a press release.