The London Underground wants to harness heat accumulated to help warm hundreds of homes. The project, which is the first of its kind in Europe, could even help reduce spiralling energy bills.
Dan Hewitt reports:
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Officers were given the touching letter at Brixton Station while they were on a reassurance patrol after yesterday's attack
The 52-year-old had previous convictions for violence but was not on the anti-terror watchlist.
In a statement Charlton Athletic said: Keith was a true hero who will be greatly missed by all the Charlton family and everyone at the club.