Next week, German officials will flip the switch and turn on the world's first coal-fired power plant to use carbon capture and storage technology, in which carbon dioxide is stripped out the plant's emissions and pumped deep underground. This "clean coal" technology has been hailed as a possible way to get cheap energy without further contributing to global warming. The 30 megawatt
Schwarze Pumpe power station, built and operated by Swedish power company Vattenfall, will produce power along with 10 tons of highly concentrated CO2 an hour. The CO2 will be loaded onto tankers and taken to a nearby gas field for sequestration [Earth2Tech].
The new Vattenfall plant is a relatively small pilot project intended to test the viability of carbon capture and storage; these
technologies have yet to be deployed in full-scale commercial plants, which typically generate hundreds of megawatts of power. The technologies are currently expensive, partly because capturing and compressing carbon dioxide into liquid requires a good amount of energy. Critics also have questioned their effectiveness in keeping emissions sealed underground [GreenTech Media].
For all these reasons, some experts have wondered whether clean coal plants are a realistic option for large-scale energy production. In the $100 million Vattenfall plant, the coal is burned in an oxyfuel boiler in the presence of pure oxygen, which results in very pure form of carbon dioxide that can easily be compressed and stored. In the United States, companies are pursuing a different approach to clean coal, using a system called integrated gasification combined cycle (IGCC) that converts coal into a cleaner-burning gas before combustion.
There are currently four IGCC plants in operation in the U.S. and Europe that could produce concentrated CO2 streams suitable for capture and storage, but these plants currently vent the emissions into the atmosphere [Earth2Tech].
There are several other demonstration plants on the drawing boards in Europe, and Vattenfall has pledged to work up to full-scale commercial power plant that uses carbon sequestration technology within 12 years.
“As a user of fossil fuels, Vattenfall is one of the owners of the climate change issue,” said Lars Josefsson, the president and CEO in a statement. “Our ambition is that this technique should become fully commercialized by 2020" [Scientific American].
Image: Los Alamos National Laboratory