NIPTON >>State and federal officials joined power industry executives for the grand opening Thursday of a massive solar power plant in eastern San Bernardino County, said to be the world’s largest solar-concentrating energy generator.

The 392-megawatt Ivanpah power plant, which delivers enough energy to supply the needs of more than 140,000 homes, is also the largest operating solar power plant in California, although larger ones are under construction.

Most of the output of the Ivanpah plant is being purchased by San Francisco-based Pacific Gas & Electric Co. and Rosemead-based Southern California Edison.

Power companies are motivated to buy renewable energy because California has mandated that renewable resources account for 33 percent of their generation by the end of 2020.

Solar thermal electric technology uses reflectors to magnify the sun’s rays, focus them on tower-mounted boilers to create steam for electrical generation.

“The Ivanpah project is a shining example of how America is becoming a world leader in solar energy,” U. S. Energy Secretary Ernest Moniz said during the dedication Thursday under warm skies in the Mojave Desert.

“As the president made clear in the State of the Union, we must continue to move toward a cleaner energy economy, and this project shows that building a clean energy economy creates jobs, curbs greenhouse gas emissions and fosters American innovation.”

In terms of carbon emission reductions, the Ivanpah project has the same effect as removing 72,000 automobiles from highways, say officials from NRG Energy Inc., one of the project’s owners.

Josie Gonzales, a San Bernardino County supervisor who could not attend the event due to a schedule conflict, said that she views the 3,500-acre facility “as a start” on solar power and hopes that it serves as a place to learn how future projects can generate the same power while taking up less land.

“Just because a project is green doesn’t mean there won’t be environmental impacts,” Gonzales said.

While this plant reduces the nation’s carbon footprint, it has significant effects on desert wildlife, she said.

Developers of the plant admitted that 44 birds had perished at the plant since all three 459-foot steam generating towers became operational in December, but said that biologists and other scientists were at work to develop strategies to reduce avian casualties.

More than 50,000 clusters of mirrors heat the water atop the each of three towers to 1,000 degrees, which results in heat bands — potentially hazardous to birds — radiating from them.

Moniz used the occasion to promote Obama’s ‘all-the-above’ energy strategy, which spreads DOE funding, through loan guarantees to all renewable energy sectors and to carbon footprint reducing technologies in traditional coal and petroleum-based power generating systems.

A $1.6 billion DOE loan guarantee was critical to the ability of the Ivanpah project to go forward due to the newness of the technology, said David Crane, CEO of NRG Energy.

The other two Ivanpah partners are BrightSource Energy and Google.

Bechtel, which engineered Hoover Dam, served as Ivanpah’s engineering, procurement and construction contractor.

Ivanpah “is this generation’s Hoover Dam,” said Toby Saey, president of Bechtel’s global power unit.

A recent report said that U.S. utility-scale solar power set a record 2.3 gigawatts installed in 2013, Department of Energy officials said.

PG&E is buying the electricity from Ivanpah units 1 and 3, while SCE is purchasing the output of unit 2, NRG officials said.

A total of about $650 million in salaries for construction and operations is expected to be paid over the next 30 years.