Underground Coal Gassification (UGC) and Coal Mine Methane (CMM)

An alternative way of getting at the coal is Underground Coal Gassification (UCG) - a technique where the coal is burnt below ground and the energy extracted. Oxygen and steam are forced into the coal seam and ignited, which breaks down the coal to form syngas containing hydrogen (H2) and carbon monoxide (CO) which can burnt on the surface to drive a turbine to release energy, water, and CO2. The big issue is that CO2 and other pollutants need to be scrubbed from exhaust, or it just becomes another polluting energy source. The solid waste stays underground, so no pit tips, and the pit head gear would look more like an oil drilling platform crossed with an electricity power station than a colliery. THe UK has the necessary precision drilling expertiese from the North Sea gas and oil field operations. The technology has been demonstrated in Russia and the US, and in operation elsewhere, but isn’t proven. If you want to know more there’s also a website dedicated to UCG. UGC may be a way of burning the thinner seams listed in the geology page.

One of the world's first experimental UGC was started between Killamarsh and Barlborough, next to what is now the M1 at Newman Spinney (visible from Woodall Services): Horizontal Direct drilling which is now widely used in oil and gas drilling.... "

Fox Earth seam

1950s image of Newman Spinney

The UGC trial ran from about 1950 to 1958 and burnt the Fox Earth seam which was almost 3m thick (although described as 'coal and dirt' and at a mere 30m depth there. In fact, some of the contemporary diagrams suggest that the Fox Earth seam was first open cast, and therefore accessible from within the open cast mine. It generated about 5MW, roughly the same as the nearby wind farm at Loscar between Harthill and Thorpe.

Note: It's probably the Fox earth (aka Wathwood) seam that was open casted at Fence between Swallownest and Woodhouse in 2010/11 where it's less than 10m deep. It's outlined in red in the photo:

Fox Earth seam

Fox Earth seam exposed at Fence near to Swallownest.

Another way to exploit the coalfieds is to capture the methane mine gas that seeps from the old mine workings - Coal Mine Methane or CMM. This is a photo of the Alkane generator on the site of the od Whitwell colliery. The methane is burnt on site and the electricity fed straight into the grid. They are good for about 10 years before the methane starts to run out.

mine methane burner

Coal Mine Methane power generator.