SAN DIEGO - A San Diego State University engineering professor working to make large-scale solar energy generation more efficient was awarded a $3.9 million federal grant, the school announced Tuesday.

The grant from the U.S. Department of Energy's SunShot Initiative will enable Fletcher Miller to build a full-scale model of his design at a testing site in New Mexico.

Miller is working on a design to superheat air to turn a turbine.

Other non-photovoltaic solar power plants use the focused heat of the sun to make steam to drive generating turbines, but water is typically scarce in spots that are best for strong, reliable sunshine.

"These (water-reliant) solar plants today are competing with cities and farmers and other users for water," Miller said. "We're trying to prove there's a better way to do this."

Partners in Miller's project include Rocketdyne, Solar Thermal Technologies and Solar Turbines.

"The hope is we prove the concept on a scale actually used to generate electricity," Miller said. "Five megawatts is a good scale to prove the component works as expected."

Miller said he expected to spend three years designing and building a larger-scale model, which would be tested in the fourth and final year of the federal grant.