This week: Clean energy
There was news this week of an innovative power plant created in Spremberg, eastern Germany, by the Swedish electricity provider Vattenfall. It is a pilot plant described as the world's first 'clean' coal-fired power station. The idea of a 'clean' coal power plant is certainly not new, with US President George W. Bush announcing in 2003 a similar initiative to build a zero-emissions coal-fuelled power plant. The project was called FutureGen, but due to unexpected cost escalations the project funding was cut this year.
The new power plant is designed to extract the carbon dioxide waste product from coal burning. This is done by burning lignite in oxygen-rich air from which the nitrogen has been extracted. This produces a stream of carbon dioxide and water vapour that is recycled back into the boiler. This process is repeated and the plant is able to concentrate the carbon dioxide. Particulate matter and sulfur is removed and the water vapour is condensed out so that up to 98 per cent of the carbon dioxide is removed.
This carbon dioxide is cooled to minus 28 degrees Celsius and liquefied. For now it is stored, with plans next year to transport and pump it into a depleted natural gas reservoir. In the future the company hopes to pipe this waste carbon dioxide directly underground. This is still a pilot project and produces a relatively small amount of energy, but with some tweaking they hope to improve the efficiency of the plant in the near future. Vattenfall is hoping that this three-year experiment in 'clean' coal will yield enough data to build a larger production plant.
It is an interesting idea and seems on the surface to be cleaner than traditional coal power plants but I doubt that it will solve any of our global energy, greenhouse gas emission and environmental problems. The process of enriching the oxygen but extracting the nitrogen is an energy costly process and will drastically decrease the efficiency of the power plant. It is said the use of such a power plant will erase the energy production efficiency gains of the past 50 years and increase the rate of consumption of fossil fuels by 33 per cent. The power plant cost will double and this will push up prices paid by the consumer by 20 to 90 per cent. The process of carbon dioxide storage is still unreliable and a small leak will undermine the whole process.
The system doesn't solve our dependence on fossil fuels and the depredation of strip mining, which is very destructive. In the United States alone, about 400,000 hectares of forest is destroyed by strip mining. In the Appalachia mountain range more than 450 mountains have been levelled, with their surrounding forests and streams annihilated, in the past 20 years. The use of explosives is extensive in coal mining, their destructive power equivalent to several atomic bombs. The process of mining is very dangerous. Hence my use of quotation marks around the word 'clean' before the word 'coal', because it is a misleading use of the word. Coal use and mining is never clean and 'clean coal power' is an oxymoron.