Hot rocks: A geothermal future?

Bill Sims Contributing columnist

Bill Sims Contributing columnist

About a year ago my wife and I took a great leap forward into the future. With the help of Hillsboro’s Shafer Heating and Cooling, we decided to install a geothermal heating and air-conditioning system at our new farmhouse. Fluid-filled coils buried deep (about 9 feet), used the year-round underground temperature of about 50 degrees to jump start the heating and cooling of our house. The result? Pretty amazing.

What convinced us to go geothermal? It was a multi-factored decision. No getting around it, the cost was steep. The 26 percent tax rebate was a offsetting and soothing balm. The proffered promise was that over some expanse of time, the efficiencies would mean significantly reduced energy costs which would help to pay for the investment. We took the leap.

So, I got to thinking. If this emergent technology was worth the investment for us, what might geothermal mean for the rest of Highland County, the state, the USA, and a world fighting to get control of climate change?

What if we had access, virtually anywhere, to the benefits of geothermal at a scale that could power the planet? A pipe dream? Maybe, and maybe very doable in central Ohio. I’ll get to that in a moment. Part of the motivation for looking into this further was a PBS program about a Berkshire Hathaway Geothermal Energy Project near the Salton Sea in the Imperial Valley of California that produces 350 megawatts of electricity, carbon free, renewable and infinitely sustainable. The fuel for this power supply emanates from the liquid magma core of the earth.

The concept is relatively simple. The molten core of the earth is about the same temperature as the surface of the sun, 10,000 degrees. But if you drill a relatively shallow 2,000 foot well or further up to two miles deep you quickly hit thermal temperatures of hundreds of degrees Fahrenheit. Fracture that hot permeable rock and send down a saline solution of water in a second well and hot water and steam in the fractured rock surges up well number one to drive the turbines that create the electricity. That’s exactly what is happening at the Salton Sea power plant. It’s 350-megawatt system is robust enough to supply about 300,000 homes. To put that into perspective, as of 2019 there were 19,333 housing units in Highland County and 16,747 households.

Amanda Kolker, project manager of the National Renewable Energy Laboratory (USDE) in Golden, Colorado, calls this “emerging dark-horse” energy solution a much more workable way by using the planet’s heat to produce electrical energy because the necessary well drilling, and rock fracturing on this scale have been done for years now. We Ohioans know that our state has a great deal of expertise in such geological work given the oil and gas industries fracking work over the last decade. In fact, according to the Ohio Department of Natural Resources, since 2010, more than 2,600 oil and gas wells have been drilled in the Utica and Marcellus shale in Ohio. That’s likely to increase given Europe’s inclination to reduce consumption of Russian natural gas and increase the import of liquefied natural gas from the U.S. Can these same companies drill for steam? My bet is that they can “walk and chew gum” at the same time. And it’s worth noting that these Utica and Marcellus Ohio wells range from 3,000 to 7,000 feet deep.

Here’s a hidden bonus. According to an Australian engineer working with the Salton Sea geothermal plant, the returning brine solution from deep in the earth contains most all the elements on the periodic table including lithium. How much? This one 350-megawatt power plant produces over 20,000 metric tons of lithium per year. That’s 71 percent of all lithium that was produced in the world in 2010, or 20 percent of what the world produced in 2021. As electric cars take off, the demand for lithium will grow exponentially.

According to a 2019 U.S. Department of Energy report the, “enormous untapped potential for generating geothermal electricity through geothermal methods could increase 26 fold by 2050. That same report indicates that “increasing the use of geothermal energy for U.S. heating and cooling can significantly contribute to national decarbonization goals to cut U.S. emissions in half by 2030 and achieve a carbon-free electric sector by 2035.

Solar and wind are great renewable energy sources. In a sense, like geothermal, they are free resources given to us by nature. But both have a serious downside. They are intermittent, not infinitely sustainable. There are times when “the sun don’t shine,” and the wind stops. Geothermally speaking, the earth’s hot rocks are a hot box that keeps on giving, rain or shine, carbon free, radiation free, and forever sustainable.

My undergraduate degree is in geography, not geology, but I’d still say it’s a good bet that geothermal is in our future, and the state of Ohio and Highland County need to get in the game. It’s all about steam heat from the bowels of Mother Earth… with a little lift from lithium.

Bill Sims is a Hillsboro resident, retired president of the Denver Council on Foreign Relations, an author and runs a small farm in Berrysville with his wife. He is a former educator, executive and foundation president.

Bill Sims Contributing columnist Sims Contributing columnist