Officials from Carlsbad energy firm NRG Energy Inc. celebrated on Friday the opening of a 66-megawatt solar facility in Lancaster.

Alpine Solar Generating Facility, the largest operational solar plant in California, has been running since earlier this year, with the power sold to Pacific Gas & Electric Co. through a 20-year agreement.

During peak daytime capacity, the plant generates enough energy to power 53,000 homes.

“As the largest operating photovoltaic facility in the state, Alpine is not only providing PG&E with a renewable source of energy, but contributing to cleaner air and a smaller carbon footprint for the state, ultimately helping meet California’s renewable portfolio standards,” said Randy Hickok, senior vice president of NRG Solar, in a statement.

Lancaster has put a heavy emphasis on solar energy in recent years, partnering with San Mateo firm SolarCity Corp. on a number of projects. It recently passed an ordinance that requires solar energy production components for all new home developments.