Meet 5 startups working to harness the Earth’s heat to save the planet • TechCrunch
A few “free” energy sources here on Earth, namely wind, solar, hydro, and geothermal. Humans have been harnessing hydroelectricity and wind for millennia, and we’re pretty good at harnessing the power of the sun. But with geothermal, we have yet to master the heat generated deep within the planet.
Most commercial-scale geothermal installations are in geological hotspots such as Northern California and Iceland. On a smaller scale, many homeowners have drilled shallow wells or buried rings in their yards for heating and cooling. But to truly unlock the potential of geothermal globally and do so profitably, we will need new ways to drill down and warm the Earth.
As the world reels in the energy transition, a lot of energy experts talk a lot about maneuverable base load power. That’s a lot of jargon. “Roleable” means that grid operators can order a plant to produce electricity at notice and the plant will supply it. And “baseload” means that the power can always be turned on, no matter the weather. Renewable energy, such as solar and wind, is not a base load energy. It would be a different story if they were combined with batteries to store energy for use when the wind is calm or the sun is not shining. The renewable energy plus battery combination is happening with increasing frequency, but batteries are still expensive and why aren’t there more options?
To truly unlock the potential of geothermal globally and do so profitably, we will need new ways to drill down and warm the Earth.
Geothermal is often touted as a carbon-free primary source of loadable energy, which is why energy is heating up with it. In a geothermal plant, a working fluid, usually water, is pumped into the ground, where it is heated before being pulled up again to run through a heat exchanger or run a turbine.
The heat source is almost limitless. The Earth is constantly creating about 44 terawatts of heat, about half of that comes from naturally occurring radioactivity. That’s about 385,000 terawatt-hours of energy released each year, far more than global energy use, which in 2019 is only 23,000 terawatt-hours. If we could harness some of the Earth’s heat, we’d have a lot of energy to use.
The potential of geothermal is coincident with the gradual decline of the fossil fuel industry, causing many engineers to rethink their careers. Incidentally, many of the drilling techniques developed for the oil and gas industry match well with what is needed to bring about geothermal flows.
There are a number of startups trying to convert geothermal from a niche energy source into one that can be widely deployed. Here are the years that I have been watching.
If there’s an award for the hottest geothermal technology, Quaise Energy will probably be the winner.