The 32 megawatt AC Long Island Solar Farm (LISF), located in Upton, New York, was the largest photovoltaic array in the eastern U.S. in November 2011. The LISF is made up of 164,312 solar panels from BP Solar which provide enough electricity for roughly 4,500 households. The project will cause the abatement of more than 30,000 metric tons of carbon dioxide emissions per year. LISF is co-owned by BP Solar and MetLife through Long Island Solar Farm LLC. Municipal utility Long Island Power Authority (LIPA) buys the 37-megawatt (49,600 hp) power plant's output, which is estimated at 44 GWh annually, under a 20-year power purchase agreement (PPA). Payments over that time are expected to total $298 million (34¢/kWh, 60¢/LIPA customer/month). The project was engineered by Blue Oak Energy and construction subcontracted to Hawkeye LLC from Hauppauge, New York. The plant earned the Best Photovoltaic Project of Year Award from the New York Solar Energy Industries Association. The panels are mounted at a fixed tilt angle of 35°, with the rows spaced approximately 18 ft 4 in (5.59 m) apart.: p.12 The solar farm uses 25 of the 1.25 MVA inverters and a 34.5 kV collector system. Since the connection to the grid is at 69 kV, and acquiring a spare step-up transformer of that capacity has a long lead time, a spare transformer is maintained onsite. Each inverter has an associated meteorological station to help researchers correlate plant output with observed and predicted weather, to help learn how to integrate photovoltaics into the power grid.
A formal case study of the development of the Long Island Solar Farm was published by the U.S. Department of Energy in May 2013.