It produces a flame and clean yet unnatural energy (9)

I believe the answer is:

acetylene

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'it produces a flame' is the definition.
The definition suggests a singular noun which matches the answer.

'clean yet unnatural energy' is the wordplay.
'unnatural' is an anagram indicator.
'energy' becomes 'e' (physics symbol as in E=mc2).
'clean'+'yet'='cleanyet'
'cleanyet' is an anagram of 'acetylen'.
'acetylen'+'e'='ACETYLENE'

'and' acts as a link.

Can you help me to learn more?

(Other definitions for acetylene that I've seen before include "cutting gas emission?" , "Gas used chiefly in welding" , "Flammable gas" , "powers industrial torch" , "Illuminating stuff also used for joining" .)

I've seen this clue in The Daily Express.

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