HyperSciences, a startup that uses rockets to drill for geothermal energy, has raised $690,000 of a $1 million funding round.

The fresh cash comes from Washington Research Foundation, Kick-Start II, Cowles Company and The Toolbox, HyperSciences CEO Mark Russell confirmed on Friday.

The Spokane, Wash. startup is designing new drilling methods to make it more cost-effective to access geothermal energy. It will use the funding to continue development of its HyperDrill and HyperBreaker tunneling machine prototypes, in addition to testing its ThermoElectric Generator (TEG) technology.

Having worked for NASA, Boeing and Blue Origin, Russell is bringing space technology to drilling. After using projectiles to drill nearly three miles to access geothermal heat, HyperSciences uses TEG technology to bring the thermal power to the surface. Russell said similar technology has been used to power spacecraft such as the Voyager or the Curiosity rover on Mars.

The company has been testing its HyperBreaker and HyperDrill at Russell’s family’s mine in Spokane for two years and demonstrated the system to Shell this past November. The machines shoot rocket-like projectiles into the earth to dig faster and more efficiently than current systems.

“Remember when the very expensive ‘Big Bertha’ got stuck in Seattle? That just wouldn’t happen with our Hyper Tunneling Machine,” Russell said. “We shoot through our problems.”

Russell, who previously launched a rideshare startup called Zebiggo in Seattle, compared the benefits of geothermal energy to those of solar and wind power. The difference, he said, is that geothermal energy is always working. “It’s like have solar or wind ‘on’ all the time,” he noted.

Since launching in 2015, HyperSciences has raised $2.6 million in angel investments and received an undisclosed amount of funding under a non-equity contract with Shell GameChanger for its HyperDrill system.