Zero-emissions gas-fired power plants are under development

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The sun rises over a mountain in the Southern Ute Indian Reservation.[/caption]

8 Rivers Capital, a North Carolina-based venture capital firm, whose engineers invented the Allam- Fetvedt Cycle, are planning to begin operating a zero-carbon-emission 280 MW Net Power gas-fired power plant in southwest Colorado by 2025. The project is called the Coyote Clean Power Project and will be located within the Southern Ute Indian Reservation. The Southern Ute Indian Tribe Growth Fund has partnered with 8 Rivers Capital on the project. The company plans to open another plant in Illinois with agricultural and processing firm Archer-Daniels-Midlands Co.

Net Power is jointly owned by 8 Rivers Capital and other industry backers. The plants will use the Allam-Fetyedt Cycle, a specialized power cycle that combines natural gas with oxygen, instead of air.

To drive the turbine, it uses supercritical carbon dioxide as a working fluid instead of steam. Most interesting about the cycle is that it recycles it does not emit emissions because it recycles the exhaust heat. The CO2 byproduct is then sequestered underground. In addition to the turbine exhaust, the cycle can use a heat source and uses a turbine inlet temperature above 800C (optimally 1,000C to 1,200C) and inlet pressure above 80 bar (optimally 200 bar to 400 bar). These qualities can make plants that use the cycle more efficient than traditional gas power plants.

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The Illinois power plant would store its carbon emissions into an existing CO₂ well, currently used to store emissions from an ethanol production plant. Where to bury the Colorado plant’s emissions is yet to be determined, but 8 Rivers notes a nearby CO2 pipeline.

US tax credits, in the amount of about $50 for each ton of sequestered CO2, would apply to both plants. The credits are intended to subsidize early-stage technologies until those technologies can be competitive with the existing fossil-fuel companies. Each of the power plants is expected to cost more than $500 million.

Design and development for both projects is due year. A final decision to build the plants is due in 2022.

Watch this video on the technology behind the new power plants.