Google is harvesting electricity directly from the Earth

A first-of-its-kind geothermal energy project has begun pumping emission-free electricity onto the Nevada grid to power local Google data centers, the tech giant announced this week.

• Geothermal energy is defined as using heat energy from the Earth for electricity generation. It represents an emission-free, always-on source of energy, since heat is continuously produced inside the Earth.

How it works: The overall idea for the Nevada project is to do for geothermal what fracking did for oil and gas – open up resources that would otherwise be inaccessible. Fervo, a startup partnering with Google on the project, does this by drilling horizontally into deep rock, then injecting pressurized fluid to create the kind of fractured, permeable rock needed to harvest geothermal energy.

Once the right kind of rock is created, Fervo gives it the ol’ sauna treatment and sends a large dose of water through fractures in the rock, which then heats the water up and generates steam back at the surface. It’s a closed-loop system, so the water gets reused after its heat energy is extracted and turned into electricity via turbines.

• Since Fervo is testing out a novel process, its Nevada plant is a relatively small project, with the capacity to generate 3.5 megawatts of electricity (for context: 1 megawatt is enough to power ~750 homes).

👀 Looking ahead… Fervo’s next geothermal energy project is scheduled to begin delivering 400 megawatts of clean, round-the-clock power to Utah’s electrical grid by 2028 as part of a state government contract. And that’s only scratching the surface (unlike the process to create geothermal energy). Overall, the Department of Energy recently said the US has potential for 90 gigawatts of geothermal electricity by 2050, equivalent to powering 65+ million homes.