At a trio of spots in rural Georgia, the state’s largest utility is boring holes thousands of feet into the Earth’s crust.
The purpose isn’t to suck up water or to hunt for rare minerals. Instead, Georgia Power is testing to see if the rocks as much as 2 miles down might be a suitable place to store carbon dioxide produced by its oil- and gas-fired power plants, instead of allowing the heat-trapping gas to escape into the atmosphere.
In recent weeks, the company has drilled boreholes in rural Georgia to evaluate whether sites are suitable for geologic carbon sequestration. It’s a technique in which carbon dioxide — the main greenhouse gas emitted by burning fossil fuels — is captured, compressed into a liquid-like state and then injected into porous rock. If CO2 from a smokestack can be collected and pumped underground, the idea is stashing it in rocks will prevent worsening global warming.
Credit: ArLuther Lee
Credit: ArLuther Lee
While Georgia Power and its parent — Southern Company — say the testing is preliminary, the federal government is pumping millions into advancing carbon storage and new, more lucrative tax credits are available for companies that pursue it. At the same time Georgia Power and other utilities add more fossil fuels to their energy mix, new emissions limits for power plants could force many to capture and store the CO2 they produce to remain in operation.
Experts say carbon capture projects carry environmental risks, including to aquifers, and critics argue the unproven technologies will serve only to allow the company to continue burning oil and gas for years to come.
The planet, meanwhile, has endured 14-straight months of record-high global temperatures. And despite the major cost and environmental concerns about the technology, bodies like the United Nations say carbon capture and storage must play a role for humanity to successfully limit climate change.
‘Permeability and porosity’
Georgia Power says the goal of its testing is to explore what’s underground and begin to determine whether geologic carbon storage might be possible at each site.
Georgia Power has drilled test bores at two sites in recent weeks — one 60 miles northwest of downtown Atlanta in Bartow County and a second on the coastal plain in Wayne County outside Jesup. It plans to punch a third hole in the ground in neighboring Brantley County within the next month. The news of the Wayne County test was first reported by the Jesup Press Sentinel.
“We’re looking for formations that have permeability and porosity so you can pump fluid into it — the compressed CO2 — but you also need to have cap rocks or seals to contain it,” said Richard Esposito, a program manager at Southern Company who specializes in carbon storage.
To do that, Georgia Power is drilling boreholes between 6,000 and 10,000 feet below ground, with the hole partially encased in cement to protect groundwater, according to work plans shared with The Atlanta Journal-Constitution.
The company is collecting rock samples about every 30 feet to assess the underlying geology, before water is pumped into the formation and pressure readings are captured to measure the rock’s permeability — the ability of liquids or gases to pass through it. When the testing is done, the company says it plans to plug each hole with cement and restore the surrounding area.
Georgia Power said it isn’t yet eyeing specific power plants to install carbon capture equipment, but experts and the federal government say the areas the company is drilling in could potentially hold CO2.
Credit: ArLuther Lee
Credit: ArLuther Lee
According to the U.S. Geological Survey, the coastal plains — including Georgia’s — are where the bulk of the country’s carbon storage capacity lies.
Areas in Appalachia like the Bartow County site are unproven, but could store carbon, too, said Ryan Pollyea, an associate professor at Virginia Tech, who studies geologic CO2 sequestration. The collision of tectonic plates that formed the Appalachian Mountains thrust huge rocks on top of others, creating the kinds of bends and folds that might be able to lock greenhouse gases away, he said.
“The exploration is important, the science is important and really understanding the rocks is important,” Pollyea added.
A checkered history
The oil and gas sector and other industries have captured carbon and injected it underground for years, but the goals of those projects are often different from what Georgia Power is pondering.
Fossil fuel production facilities typically capture CO2 and inject it underground to force more oil and gas to the surface, not necessarily to lock the carbon away permanently.
Off the coast of Norway in the North Sea, the Sleipner Project has been separating CO2 from the oil and gas it produces and returning it to a massive sandstone formation beneath the waves. Sleipner has been in operation since 1996 and was the world’s first commercial carbon storage project. As of late last year, the U.S. had 15 carbon capture and storage projects in operation and another 121 planned across the country, according to a report from the nonpartisan Congressional Budget Office. Most active ones capture emissions from plants that produce natural gas, ethanol fuel or ammonia used in fertilizer, the report said.
But pulling CO2 from a power plant’s smokestack, transporting the gas by pipeline or truck and then pumping it into porous rocks is a different and more expensive proposition — one that has not yet succeeded on a large-scale in the U.S.
Credit: undefined
Credit: undefined
Among the notable failures is the FutureGen “clean coal” project, which tried to retrofit a coal-fired power plant in Illinois with a type of carbon capture technology. The plan was to pipe collected CO2 to a site 30 miles away and then pump it into a deep, saline aquifer. But the project — which had been projected to cost $1.65 billion — was abandoned in 2015 after it failed to progress and lost funding from the U.S. Department of Energy.
With backing from the DOE, Southern Company has operated the National Carbon Capture Center since 2009 in Wilsonville, Alabama, to research and develop carbon capture and conversion strategies.
Still, Southern, too, has a fraught history with the technology.
The Mississippi-based Kemper project, which aimed to generate electricity by burning a natural gas-like substance made from low-grade coal and capture CO2 in the process, saw its price tag balloon from $2.4 billion to $7.5 billion. Southern pulled the plug on Kemper in 2017, but the company still faces a whistleblower lawsuit over claims it misused federal funds for the project.
Mark Berry, Southern Company’s senior vice president for research and development, said the exploratory drilling is “not related” to Kemper, calling it “just a totally different situation.”
Water and earthquake concerns
Beyond the cost worries, underground carbon storage could present environmental hazards that need to be considered, said Pollyea, the Virginia Tech professor.
Though the formations where carbon could be injected sit thousands of feet below Georgia’s groundwater deposits — including the massive Floridan aquifer, which underlies much of the Southeast — boring through an aquifer could threaten groundwater supplies if the drilling is not done properly, Pollyea said.
“If your wells aren’t cased properly, if seals are broken or breached, you have the potential to contaminate an aquifer,” he said.
Credit: undefined
Credit: undefined
Earthquakes are another potential concern and Pollyea pointed to Oklahoma as a prime example, which has experienced a rash of earthquakes since 2009.
Research has linked the seismic activity to the injection of water into the ground to break loose fossil fuel deposits, a process known as “fracking,” as well as the oil and gas industry’s practice of pumping spent wastewater underground.
“This is an area that is being very carefully looked at for its potential to cause problems,” Pollyea said.
Asked about those worries, Georgia Power spokesman John Kraft said, “Many experts have noted safety concerns related to CO2 storage in geologic formations can be effectively addressed.”
Other critics say carbon capture simply distracts from more proven climate change solutions.
“To truly reduce carbon pollution, Georgia Power needs to stop experimenting and move forward with clean, reliable, renewable energy,” said Mark Woodall, the conservation chair for the Sierra Club’s Georgia chapter.
Kraft said the company welcomes input, but “has an obligation to serve customers with reliable, affordable energy 24 hours a day, every day,” and will continue to explore new technologies, including carbon capture and storage.
Next steps
Carbon storage’s steep cost has been one of the chief impediments to widespread use by the power sector, Pollyea said.
But sweetened federal incentives — plus tightened emissions limits — could change the calculus for utilities.
Long-standing tax credits for capture and sequestration were recently enhanced and extended until the end of 2032 by President Joe Biden’s signature climate and health care law, the Inflation Reduction Act.
The federal Environmental Protection Agency, meanwhile, earlier this year finalized stricter emissions regulations for existing coal-fired power plants and new gas ones. The new rules would force many facilities to slash their CO2 emissions by 90% as soon as the early 2030s, or shut down. The limits face legal challenges, but could mean many facilities will need to begin capturing carbon to stay in operation.
Georgia Power has said it plans to shutter all of its coal power plants by 2035, but recently hinted it could leave some units running longer than previously planned.
So far, Georgia Power has not submitted any formal filings with state regulators at the Georgia Public Service Commission about its exploratory drilling. A PSC spokesman said the commission was unaware of the company’s test borings until contacted by the AJC.
Kraft, the Georgia Power spokesman, would not disclose what the company has spent so far investigating storage sites, saying it would submit costs to the PSC “as appropriate and required.”
But more information about the utility’s carbon storage vision may come to light soon.
Georgia Power is scheduled to file its next long-range energy plan with the PSC in late January next year. Kraft said the company expects to discuss the project with regulators, along with other research and development initiatives.
Still, any carbon storage in Georgia is likely years from becoming reality.
CO2 injection wells are regulated by the EPA and Georgia Power has not sought permits yet. Any approvals are expected to take about two years after an application is received.
A note of disclosure
This coverage is supported by a partnership with Green South Foundation and Journalism Funding Partners. You can learn more and support our climate reporting by donating at ajc.com/donate/climate.
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