NET Power demonstration plant

NET Power’s plant in Texas, USA, utilises a new process to generate electricity without generating greenhouse gas emissions. Called the Allam Cycle, after its inventor Rodney Allam, the process combusts natural gas with pure oxygen to produce supercritical CO2 as a working fluid. This then drives a first-of-its-kind CO2 turbine. Using pure oxygen, rather than air, eliminates any chance of producing nitrogen oxide, one of the world’s worst air pollutants.

Whilst some of the CO2 produced through the Allam Cycle is reheated and used again in the combustor to improve efficiency of the Allam Cycle, the remaining CO2 is removed. Because this is a high-pressure, high-purity by-product, it can be sequestered underground without further compression for Enhanced Oil Recovery (EOR). The only other by-product is a small amount of water.

This approach contrasts with the traditional process where gas is burned with air to create heat. This, in turn, converts water to steam to power the generating turbine, producing a lot of CO2 (and nitrogen oxide) that is released into the atmosphere.

WSP has been working with NET Power since 2013, helping to take the technology from conceptual design to a demonstration of the combustor and testing of the process.

Our Manchester office was commissioned in 2016 to provide detailed engineering services for modifications that enabled the demonstration plant to also function as a combustor test facility. This combustor test rig design required close collaboration between NET Power and 13 of WSP’s offices – across four countries.

Now that the process has been proven to work, the next step for NET Power is to build a full-size 300MWe plant.

A zero-emission fossil fuel

With urgent action needed to cut the world’s carbon emissions, this technology has the potential to be used with coal and natural gas. We hope it can contribute to reducing emissions from fossil-fuel power production.

In the UK, where the last coal-fired power plants are set to close by 2025, the technology could help the country meet its renewable energy target. It offers a sustainable alternative that would also be cheaper to build and run than a traditional gas-fired power plant.

_{*Banner image courtesy of NET Power and McDermott}