German:

wood: 17-20 MJ/kg
Lignit: 20-25 MJ/kg
'soft' Braunkohle: 25.1-26.8 MJ/kg
'hard' Braunkohle: -28500 kJ/kg
'flame' Steinkohle ( = stone coal): -32.85 MJ/kg
'gas flame' Steinkohle: -33.9 MJ/kg
'gas' Steinkohle: -35.0 MJ/kg
'fat' Steinkohle: -35.4 MJ/kg
'eating' Steinkohle: -35.4 MJ/kg
'lean' Steinkohle: -35.6 MJ/kg
anthracite: -36.0 MJ/kg

English:

lignite/brown coal: 10-20 MJ/kg
sub-bituminous coal: 20-28 MJ/kg (with most sold in the US near the lower limit)
bituminous coal: 24-35 MJ/kg
anthracite: 26-33(?) MJ/kg

_{*Lunatic*, n.
One whose delusions are out of fashion.}