One with backbone investing billions in green energy tax (10)
I believe the answer is:
vertebrate
'one with backbone' is the definition.
(I've seen this before)
'investing billions in green energy tax' is the wordplay.
I cannot really understand how this works, but
'billions' could be 'b' (abbreviation) and 'b' is found within the answer.
'green' could be 'vert' (heraldic term for green) and 'vert' is located in the answer.
'energy' could be 'e' (physics symbol as in E=mc2) and 'e' is located in the answer.
'tax' could be 'rate' (rate is a kind of tax) and 'rate' is present in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Another definition for vertebrate that I've seen is " One with backbone".)