Frugal person saving the planet, not a skinflint (10)

I believe the answer is:

economiser

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'frugal person' is the definition.
'economiser' can be an answer for 'person' (economiser is a kind of person). I'm not sure about the 'frugal' bit.

'saving the planet not a skinflint' is the wordplay.
'saving the planet' becomes 'eco' (as in eco-friendly).
'not' becomes 'no' (negative).
'a skinflint' becomes 'miser' ('miser' can be a synonym of 'skinflint').
'eco'+'no'+'miser'='ECONOMISER'

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I've seen this clue in The Telegraph.

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