From  By David Roberts – Oct 21, 2020

Geothermal power is the perpetual also-ran of renewable energy, chugging along in the background for decades, never quite breaking out of its little niche, forever causing energy experts to say, “Oh, yeah, geothermal … what’s up with that?”

Well, after approximately 15 years of reporting on energy, I finally took the time to do a deep dive into geothermal and I am here to report: This is a great time to start paying attention!

After many years of failure to launch, new companies and technologies have brought geothermal out of its doldrums, to the point that it may finally be ready to scale up and become a major player in clean energy. In fact, if its more enthusiastic backers are correct, geothermal may hold the key to making 100 percent clean electricity available to everyone in the world. And as a bonus, it’s an opportunity for the struggling oil and gas industry to put its capital and skills to work on something that won’t degrade the planet.

Vik Rao, former chief technology officer at Halliburton, the oil field service giant, recently told the geothermal blog Heat Beat, “geothermal is no longer a niche play. It’s scalable, potentially in a highly material way. Scalability gets the attention of the [oil services] industry.”

In this post, I’m going to cover technologies meant to mine heat deep from the Earth, which can then be used as direct heat for communities, to generate electricity, or to do both through “cogeneration” of heat and electricity. (Note that ground-source heat pumps, which take advantage of steady shallow-earth temperatures to heat buildings or groups of buildings, are sometimes included among geothermal technologies, but I’m going to leave them aside for a separate post.)

Before we get to the technologies, though, let’s take a quick look at geothermal energy itself.

Read more…