Old-fashioned fuel was not good for cooking (4,3)

I believe the answer is:

town gas

'old-fashioned fuel' is the definition.
(historical type of fuel)

'was not good for cooking' is the wordplay.
'good' becomes 'g' (abbreviation).
'for cooking' indicates an anagram.
'was'+'not'+'g'='wasnotg'
'wasnotg' with letters rearranged gives 'TOWN GAS'.

I've seen this clue in The Times.

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