NET Power says that it achieved first fire of its supercritical carbon dioxide (CO₂) demonstration power plant and test facility in La Porte, Texas, including the firing of a 50-megawatt Toshiba combustor.

Following testing, the company says that the combustor will be integrated with the turbine and power will be generated.

The company says that first fire is a critical milestone for the demonstration plant, and says that it validates the fundamental operability and technical foundation of NET Power's power system. The achievement also confirms the operation of Toshiba's combustor at commercial scale.

NET Power is a collaboration between Exelon Generation, McDermott and 8 Rivers Capital.

The plant is designed to demonstrate NET Power's Allam Cycle technology. Using carbon dioxide as a working fluid to drive a combustion turbine, the Allam Cycle eliminates virtually all emissions from natural gas power generation without requiring carbon capture equipment.

Workers with Toshiba make adjustments to equipment in February 2018, prior to the start of testing. Credit: David WagmanIn parallel with the demonstration plant tests, NET Power is working to develop commercial-scale 300 MW natural gas plants.

Existing natural gas plants burn natural gas with air, which is a mix of oxygen and nitrogen. These technologies emit CO₂, which can be difficult to separate from the nitrogen and residual oxygen. This often makes carbon capture uneconomic for traditional power plants. NET Power uses what it says is an oxy-fuel, supercritical CO₂ power cycle that produces electricity efficiently while eliminating most air emissions.

The NET Power system burns natural gas with oxygen, as opposed to air. Additionally, instead of using steam, the cycle uses high-pressure CO₂ to turn a turbine. NET Power produces only electricity, liquid water and pipeline-ready CO₂, as well as argon and nitrogen, which may be resold. The company sees a potential market in using a stream of CO₂ for enhanced oil recovery.