On 20/01/2020 12:12, Chris Hogg wrote:
On Mon, 20 Jan 2020 11:43:51 +0000, Andy Burns
wrote:

Chris Hogg wrote:

Do you know how much coal capacity we have, in total?

wiki says 7.3 GW, are any closed ones kept moth-balled for
balancing/reserve purposes? I suppose you can't leave a mountain of
coal out in the rain indefinitely ...

The company I used to work for had their own coal-fired power station
up until about 1970, to supplement the grid or to use when the grid
went down. The man who managed the coal stocks told me that the stock
decreased naturally every year, by about 10% IIRC (which seems a lot,
I may have mis-remembered), simply due to aerial oxidation of the
stockpile. In the extreme, they can suffer spontaneous combustion.
http://tinyurl.com/wcv5jay

That sounds like quite a lot to me too. However I imagine that the coal
containing more volatiles might well lose methane and perhaps other
hydrocarbons by evaporation. It might also dry out a bit in spite of
being left in a pile on the ground in the open: after all, underground
there is nowhere for the water to drain to.

Point noted about spontaneous combustion (see "Titanic").