Conservative estimates put North Dakota’s recoverable coal reserves at around 25 billion tons, enough to last some 800 years at current usage rates. Pair that with the state’s rare underground geology, and you have a recipe for demonstrating a high-profile—but still aspirational—clean power technology.

Minnkota Power Cooperative has committed to leverage the resources beneath its feet with Project Tundra, an ambitious carbon capture and storage (CCS) initiative conceived in 2015. Engineering and design, in the works since 2018, were helped this year by federal government incentives and a new law that allows cooperatives to receive direct payments for clean energy initiatives.

“We understand that we’re incredibly fortunate to have the geology we have right beneath our generation site,” says Mac McLennan, Minnkota’s president and CEO. “Most co-ops don’t have that as a readily available resource.

“And now, with programs in the Inflation Reduction Act and other federal initiatives including grant and loan opportunities for CCS, we see a real opportunity for Project Tundra to be successful.”

The Grand Forks-based generation and transmission cooperative is the wholesale power provider for 11 distribution co-ops in eastern North Dakota and northwestern Minnesota.

Project Tundra is estimated to cost around $1.45 billion to construct and will become part of Minnkota’s Milton R. Young Power Plant near Center, North Dakota. Once built, it will collect up to 4 million metric tons of CO2 per year from the exhaust streams of the 700-megawatt plant’s two units.

The CO2 will then be injected into seams of porous rock located at least a mile beneath the surface, where it will remain permanently sequestered. 

“We recognize that we’re going to live in a carbon-managed world, whether it be through public policy changes, regulation or societal expectations,” McLennan says. “At the same time, the Milton R. Young Station provides critical baseload reliability and resiliency to our system. If we can capture and permanently store the carbon emissions, it will allow us to retain a dependable generation source while meeting environmental targets.”

The Minnkota project is expected to draw significant attention in the wake of the Environmental Protection Agency’s recently proposed rule to regulate emissions from coal and natural gas-fired power plants. EPA’s proposal claims that carbon capture and storage is commercially viable today.

“EPA suggests that carbon capture is viable today, but Project Tundra is a first-of-its-kind demonstration,” says NRECA CEO Jim Matheson. “These are early steps in a long process to develop CCS technology and to demonstrate its usefulness in a dynamic energy sector.

“The U.S. economy will only require more electricity as our country grows. Project Tundra is one of several important pieces of the puzzle to ensure we can continue to meet our overall objective: reliable, affordable electricity for every American served by a co-op.”

Minnkota officials also see potential for an emerging carbon credit market adding to Project Tundra’s future value, says Craig Bleth, the G&T’s vice president of project development.

“There are entities purchasing carbon removal credits today,” he says. “It’s something we’ll certainly be keeping our eye on.”

Young Station has been online since 1970, operating through the height of coal-based generation in the U.S. Now, amid widespread coal-plant closures, Project Tundra offers an opportunity for the plant to serve as a blueprint for coal’s role as a global energy resource with significantly less CO2 emissions.

Bleth’s team is hoping to have a construction-ready design for Project Tundra completed in early 2024, with a final decision on whether to proceed with construction expected in spring of next year.

'Years of research'

Minnkota began considering Young Station for carbon capture and storage in 2015, in part because of its operating performance as a mine-mouth generation site. Geological strata beneath the site is well suited for indefinite storage of CO2 without presenting known threats to soil, water or the environment, says McLennan.

“Years of research — from test wells to seismic surveys — have all shown that carbon can be safely and permanently stored in these geologic formations,” he says.

But, he adds, advancing technology at the proposed size and scale isn’t possible without strong state and federal support. The G&T has received a $100 million low-interest loan from the state of North Dakota and is also pursuing additional project investors. Co-op supported changes in federal law now permit electric co-ops and other tax-exempt utilities to claim tax credits for clean energy initiatives as direct payments from the U.S. Treasury, a major benefit sought by co-ops for decades.

“The direct pay option for these [tax] credits can help bring an entirely new pool of investors to the table. This is proving to be critical as inflation and supply chain challenges have put pressure on the project costs,” says McLennan.

Several test wells at the Young Station site have been drilled to a depth of 10,000 feet. Besides sampling and data collection, seismic geophysical survey work is also being conducted, says Shannon Mikula, the G&T’s environmental manager and geologic storage lead for the project.

“The state has the capacity to store about 252 billion tons of CO2 in formations. That’s equivalent to 50 years of national carbon production from energy generation,” says Mikula.

North Dakota, she adds, also offers an ideal regulatory structure to advance CCS technology. Currently, it’s one of only two states with authority to permit its own Class VI injection wells for CO2 storage.

Minnkota Power anticipates that Project Tundra could be fully operational by 2028.

“At that time, we’ll be on track to capture and store up to 4 million metric tons annually,” says Bleth.

While final engineering and design work is in progress, completing the actual buildout within four years remains challenging, he says. Skilled construction workers will have to be recruited, and some work may have to be scheduled only during warm seasons to avoid harsh weather conditions.

“Constructing a facility of this size in a rural area will require a significant amount of coordination,” says Bleth. “Our winter season in North Dakota presents additional construction challenges that will need to be planned for.”

Fully operational, Project Tundra is expected to be the world’s largest carbon capture and storage facility, and the experience gleaned from its operation could advance carbon mitigation options for other suitable sites.

“Our hope is that as this technology develops, each successive project will continue to improve efficiencies and lower costs to a point that carbon capture becomes a well-demonstrated and applied technology worldwide,” says Bleth.

Co-op leaders point to the challenges of extreme weather events, inadequate reliability of renewable generation and volatility in power supply markets as reasons to preserve and continue modernization of fossil fuel generation while meeting environmental challenges.

“Time and time again, we find that our coal-based resources are the most reliable and resilient in our power supply mix,” says McLennan. “While we have robust wind and access to hydro power, coal remains the backbone of our system. With Project Tundra, we don’t have to choose between environmental goals and the reliability of our grid.

“We support moving toward a more sustainable energy future, but it’s not something that can happen with the flip of a switch,” McLennan says. “It will take decades of planning and unprecedented technology development to achieve significant carbon reduction. Our goal is for Project Tundra to help drive some of that change.”