Harvesting energy from CO2 emissions

Published on
August 6, 2013

The emissions from power plants and factories are a source of energy. When combustion gases mix with the outside air, energy is released. This was discovered by environmental technologists of Wageningen UR (University & Research center) and Water Technology Institute Wetsus. They also devised a method to capture that energy and turn it into electricity.

Discovery makes climate goals attainable

"Coal-fired and gas-fired power plants can generate at least six percent more energy with this technology, without increasing their CO2 emissions," says Cees Buisman, Professor of Biological Recovery and Reuse Technology at Wageningen University and director of Wetsus. "If this technology is used worldwide, we will easily meet the objective of the Kyoto climate change conference." And it is affordable, Buisman adds. "When applied on a large scale it costs about 4 cents per kilowatt-hour to generate power from flue-gas emissions."

Immediately patented and published

The environmental technologists first experimented with electricity production from carbon dioxide in May and June 2013. When they discovered that it worked they immediately patented the technology and wrote a scientific article about it. "When you do such a discovery, you better publish it as quickly as possible, before someone else comes up with the idea," tells Buisman. The article was submitted to the prestigious scientific journal Environmental Science & Technology on July 5. In no time the editors of that magazine contacted the researchers to inform them that this would be their opening article in the Environmental Science & Technology Letters of July 23. As soon as the article was published, companies and researchers from around the world started contacting the Dutch researchers. Collaboration with energy companies will help to quickly develop and up-scale the technology.

Blue Energy

The Sub-department Environmental Technology of Wageningen University and Wetsus have many years of experience  in generating power from a mix of fresh and salt water, using the so-called Blue Energy Technology. "The difference in salt concentration sets the ions in motion, which generates energy", explains Buisman. When the mixture is then passed through two electrodes - the one covered by a membrane that reacts with positively charged ions and the other coated with a membrane that lets the negatively charged ions through - that energy can be converted into power. There are no membranes that can split the negatively and positively charged particles in gases. However, those gases can be added to deionized water, which can then be pumped through a spacer channel between the two ion-exchange membranes.

Ion Current Technology

There are more than ten PhD students at the sub-department Environmental Technology that are working on Ion Current Technologies. "Ions can be put in motion by differences in concentrations, but also by bacteria," says Buisman. For example, the Environmental Technology of Wageningen University has also developed a method to capture the energy that is released during interactions between soil bacteria and plant roots. This technique is now being applied in practice by Plant-e, an Environmental Technology spin-off.