“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. “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.”
Quickly patented discovery
The environmental technologists first experimented with electricity production from carbon dioxide in May 2013. When they discovered that it worked, they immediately patented the technology and wrote a scientific article. “When you do such a discovery, you better publish it as quickly as possible, before someone else comes up with the idea,” tells Buisman. As soon as the article was published, companies and researchers from around the globe started contacting the Dutch researchers. Collaboration with energy companies will help to quickly develop and up-scale the technology.
Wageningen University and Wetsus have a lot of experience in generating power from a mix of fresh and salt water, 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.
“Ions can be put in motion by differences in concentrations, but also by bacteria,” says Buisman. For example, 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.