RWE's algae project

The CO₂ that emerges during the combustion of fossil fuels can be turned to good account, and with little environmental impact at that. With this objective, RWE Power researched the binding of CO₂ by micro-algae in a pilot plant at Niederaussem.

Micro-algae need carbon dioxide to grow. Like all plants, micro-algae absorb CO₂ via photosynthesis, i.e. with the aid of light, but in doing so grow significantly faster than land-based plants. An increased growth rate is achieved by the controlled addition of CO₂ using CO₂ sources that have a higher CO₂ content than air. Hence, flue gases, e.g. from lignite-fired power plants, are ideal for producing algae. No separation of the CO₂ from the flue gas is necessary, since the flue gas can be used directly.

For the purpose of testing the micro-algae technology in depth and developing it further, RWE Power, in cooperation with experienced partners, erected at the Niederaussem power plant location a facility for binding carbon dioxide from the power station's flue gases, and operated it for a period of three years until the end of 2011. The CO₂ contained in the flue gas was dissolved in an algae slurry and taken up by the algae for growth.

RWE's algae project was able to show that micro-algae grow just as well with flue gases from the lignite-fired power plant as with pure CO₂. Furthermore, recent developments of our project partner Phytolutions made it possible to increase the efficiency of the entire process. Operating the plant over a three-year period under real conditions has aided in advancing the technical development and highlighting essential aspects for the planning of future large-scale facilities.

The project was completed as scheduled at the end of 2011.