Renewable energy company Alkane revealed this week that it has completed the connection of two methane-powered generation plants to the electricity supply grid.
Fuelled by methane captured from abandoned coal mines, the two sites, at Bevercotes and Markham, have a combined generating capacity of 5.4MW.
The Nottingham-based company said two further coal mine methane (CMM) sites, at Mansfield and Whitwell, Derbyshire, are making ‘excellent progress’. When fully functioning they will contribute another 2.7MW of generating capacity, and are expected to be operational by this autumn.
CMM is formed when methane trapped inside layers of coal is released during mining. The gas is regarded as a hazardous byproduct, disposed of by mining companies during their operational life. After a mine is closed a large quantity of CMM remains in disused shafts and continues to escape into the atmosphere. Methane is considered to be a significant contributor to global warming, with an environmental impact 20 times that of carbon.
Alkane maps gas reserves in abandoned pits and applies a vacuum to the former workings. As the pressure decreases inside the mine, methane is desorbed from the coal and channelled to the surface, where an extraction plant processes the gas. Alkane’s CMM plants in the UK are expected to capture approximately 22,000 tonnes of methane in 2005, which equates to CO2 savings of around 500,000 tonnes. An equivalent saving of CO2 would be produced by building 285 1MW wind turbines, the energy company claims.
When Alkane unveiled its first international CMM plant in Germany in 2003 it accused the UK government of not doing enough to aid the fledgling CMM industry, contrasting it with the support given by the German authorities. Alkane chief executive Dr Cameron Davies said that the situation had improved, however. ‘Climate Change Levy exemption benefits, coupled with high electricity prices in the UK, have significantly improved the economics of our coal mine methane operations. The successful completion of our plants at Bevercotes and Markham represents a major step forward in our electricity generation business,’ said Davies.