GREELEY — The city of Greeley said Wednesday it will work with three companies to build a 500-kilowatt solar farm that will generate 15 percent of its wastewater treatment facility's electricity needs.

The city will join Oak Leaf Energy Partners of Denver, Enfinity America Corp. of San Francisco and Intermountain Electric of Denver in the project. Construction on the solar farm, Weld County's largest, will begin this month and is scheduled to be finished in late December, the city said.

The photovoltaic array of more than 2,100 panels occupying three acres will generate an average 726,000 kilowatt-hours of electricity annually. The facility will emit 745 fewer tons of carbon dioxide.

Enfinity, the project's financier, owns and operates the photovoltaic arrays and will sell the solar electricity it generates to the city.

Oak Leaf Energy Partners, the project's developer, is providing site-planning, tax and financial structuring and negotiating.