How Sologen’s plan to turn abandoned oil and gas wells into geothermal power producers could replace coal power in Texas.

Two weeks ago, San Antonio resident Frank Smith signed a letter of intent to purchase an abandoned oil well in Brazoria County. But it’s not the oil he’s interested in; it’s the super-heated water at the bottom of the pipe that he hopes to run through a turbine on the surface, turning it into a reliable source of electricity to feed into Texas’ straining power grid. The well would take only a few months to set up, requires no toxic chemicals, and gives off no air pollution. Best of all, a researcher at one of the most prominent geothermal labs in the country thinks the technology Smith and a handful of others in Texas are investing in today could be rapidly duplicated at abandoned and closed oil wells across much of the state — ultimately providing enough energy to displace dozens of coal plants by 2050.

“I could never leave Texas and retire a billionaire,” boasts a confident Smith, owner of the SA-based clean-energy outfit Sologen. “But that’s not the goal. The goal is to seed an industry.”

The need for power in Texas was prominently on display last week, as triple-digit August temperatures and corresponding record-setting energy use hit the state hard day after sweat-soaked day. The operator of the bulk of the state’s power grid — the Electric Reliability Council of Texas — called for voluntary energy reductions between the peak-use hours of 3 p.m. and 7 p.m., and still we broke new state records three days in a row, topping out at more than 2,500 megawatts above last summer’s previous high of 65,776 megawatts. We would have broken the record again last Thursday if ERCOT hadn’t declared a Stage 2 emergency and called on industrial partners to shut down up to 1,000 megawatts of power to avoid rolling blackouts.

San Antonio-owned CPS Energy also encouraged conservation, tweeting last Thursday: “Here we go again... Heat continues to put strain on state electric grid. Conserve any way you can…”

While much of the electricity provided during the hottest times of the day is made by quick-firing natural gas, the bulk of power consumed in Texas is provided by coal. And even as state utilities struggle to meet the unprecedented demands of record-breaking temps and rising populations, coal power — indicted in everything from increased heart attacks, asthma cases, and weather-weirding climate change — is increasingly under assault. As the U.S. EPA continues to fight Texas over greenhouse gas emissions the state’s leadership refuses to regulate, new rules rolled out last month require fast reductions of soot and lung-damaging nitrogen oxides and sulfur dioxide — reductions that will inevitably lead to many older coal plants shuttering.

CPS Energy, already committed to closing down its oldest and dirtiest coal plant, JT Deely, years early, doesn’t expect to be able to meet the EPA’s deadline for bringing its next oldest coal plant, the Spruce 1, into compliance. In a letter to the EPA last fall, Angela Donaubauer Rodriguez, environmental and sustainability manager at CPS Energy, wrote the EPA that the lower limits for nitrogen oxides could not be met by Spruce 1. In a second letter, dated February 7, 2011, she wrote the new lower limits could be met, but not without “significant modifications,” and not by the EPA’s deadline of January 2012. And if coal is not a sure bet for future baseload power needs, neither is nuclear.

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