SolarCity rose to prominence leasing solar panels, not making them.

Now the San Mateo company does both. At an event Friday morning in New York, SolarCity will lay claim to one of the solar manufacturing world’s top titles — Most Efficient Rooftop Panel on Earth.

And in a shift for an industry that relies on imported hardware, those panels will be made in the United States.

SolarCity CEO Lyndon Rive and board chairman Elon Musk will report that the company’s new panels can convert into electricity 22 percent of the energy that falls on them in the form of sunlight. That tops the 21.5 percent efficiency of panels made by San Jose’s SunPower Corp., whose panels are considered to be the most efficient for rooftop arrays. The efficiency of SolarCity’s panels was deteremined by the Renewable Energy Test Center, a third-party testing firm.

SolarCity’s new gear comes from the company’s 2014 purchase of Silevo, a startup with a streamlined process for making high-efficiency cells.

Starting this month, small quantities of the new panels will be built at a pilot factory in Fremont, inside a building once leased by the ill-fated Solyndra. But sometime in the next two years, production will shift to a massive factory SolarCity is building in Buffalo, N.Y. The factory will be capable of producing enough solar panels in one year to generate a gigawatt of electricity, roughly the output of a nuclear reactor.

China has largely unseated the United States as the center of solar manufacturing. The rise of inexpensive Asian panels is, after all, one of the main factors that doomed Solyndra, whose tube-shaped solar panels were too pricey to compete.

But New York state officials offered SolarCity a tempting deal to place its factory in Buffalo.

Construction is being funded by the Research Foundation for the State University of New York, which is developing a technology park on the site of an old steel mill. The state expects to invest $750 million in the factory, while SolarCity will spend about $5 billion on the plant’s capital costs and operational expenses over the next 10 years.

In addition, Silevo’s manufacturing process requires the kind of highly skilled labor available in the Buffalo area, said SolarCity spokesman Jonathan Bass. And since SolarCity will install its panels in the United States, making them here lowers shipping costs.

“You put all these things together, and we believe it’s more cost-effective to build them here than overseas,” Bass said. “We’re building the world’s most efficient panel, and we’re doing it in America.”

David R. Baker is a San Francisco Chronicle staff writer. E-mail: dbaker@sfchronicle.com Twitter: @DavidBakerSF