As of May 30, 2018, a supercritical carbon dioxide demonstration power plant began operation in Texas, USA. Operated by NET Power, LLC, the technology is powered by natural gas and generates electricity using CO2 itself to run the turbine. The technology–called the “Allam Cycle”–may eliminate “virtually all emissions from natural gas power generation without requiring expensive … carbon capture equipment.”
Traditional natural gas power plants burn gas using air and use water to crank the turbine. A by-product of the process is CO2 which often is released into the atmosphere or is attempted to be captured using expensive equipment.
The Allam Cycle replaces the water with supercritical carbon dioxide which operates as both a liquid and a gas. Oxygen, CO2, and natural gas are fed into a combustor; the gas ignites; the by-products “are hot water and a lot of supercritical CO2 which acts as an efficient working fluid for driving the adjacent turbine.” Using CO2 to run the turbine improves efficiency, avoids energy losses, and eliminates parts of the process needed by steam-electric power plants.
The end result could be the production of “low-cost electricity from natural gas while generating near-zero atmospheric emissions, including full CO2 capture.”
The plant fired on May 30 is a demonstration facility. If successful, NET Power predicts the building and deployment of commercial-scale power plants starting as soon as 2021.
“If it plays out as advertised, it could be an actual game changer.”