300-MW Natural Gas Allam Cycle Power Plant Targeted for 2022

Testing continues at NET Power for a much-watched project that is demonstrating production of low-carbon natural gas power. The project is using a supercritical carbon dioxide (sCO2) cycle, and its developer is confident that the technology will be commercially deployed in 2022.

Mike McGroddy, principal at 8 Rivers Capital, the venture capitalist firm that is developing the novel “Allam Cycle” in use at the 50-MWth (25-MWe) plant, told POWER on Nov. 19 at the NARUC Annual Meeting in San Antonio, Texas, that the project has entered a “longer-duration testing phase.” 

NET Power achieved first-fire of its commercial-scale 50-MWth (25-MWe) combustor engineered and manufactured by Toshiba Energy Systems & Solutions in cooperation with Parametric Solutions in May 2018, after two years of quiet development. The first-of-its-kind sCO2 combustor is critical to the unique cycle, and it is the same size as ones planned for commercial units. 

[For an in-depth look at the Allam Cycle and the La Porte test project, see, “Inside NET Power: Gas Power Goes Supercritical,” from POWER’s April 2019 issue.]

But since that pivotal milestone, little news has emerged from the company, for whom quiet development is apparently customary, even as the project garners substantial interest from international organizations and the regulatory world.

McGroddy said the project was last year connected to the ERCOT grid, but it is only producing power for internal use owing to “variable output” associated with the tests. He noted that the demonstration project will continue for an unspecified period. 

“Our plan is to keep it operating long term. We’re going to test different vendors, different equipment, [and use it as a] long-term test facility as we grow and expand our supply chain vendors,” he said. “If someone wants to design something especially for our cycle, we can test it and we can bring on other turbine suppliers to test at the facility. So the goal is to have it as a long-term test-bed for any future improvements to the system.”

Meanwhile, work continues to develop a full 300-MWe commercial plant, and NET Power is currently targeting 2022 for first power. “We’re looking at maybe four to five sites in the U.S. actively right now, potentially more if those conversations [progress]. We’re looking at some sites overseas—Europe, Middle Eastern countries. So it’ll be a question to see which one gets the first evolution, but we’re pretty confident that it’ll be in the U.S.,” McGroddy said, noting the 45Q carbon capture tax credit and growing needs for low-cost CO2 for industrial processes—such as for enhanced oil recovery (EOR), where injected CO2 can increase oil recovery by 10% to 25%—poses attractive incentives for first deployment. 

At one site, still unnamed, engineering work is ongoing, and NET Power and partners are conducting pre-FEED studies for other sites, he said.

In tandem, 8 Rivers is also developing a 300-MW Allam Cycle coal plant. The company this October garnered the Department of Energy’s (DOE’s) backing as part of its Coal FIRST initiative to perform a pre-FEED study for a project to integrate coal gasification and the Allam Cycle core technology currently being proven at the La Porte facility. 

According to the DOE, 8 Rivers’ design could boost the net efficiency percentage of a coal plant to the mid-to-high 40s. It also promises “higher heating value with carbon capture; ramping speeds in-line with natural gas combined cycle technology, with the potential to exceed that performance; significant water savings (50% to 60%) compared with integrated gasification combined cycle technology; fuel flexibility; and the ability to store electricity as chemicals when power is in low demand.”

Sonal Patel is a POWER senior associate editor (@sonalcpatel, @POWERmagazine)