He argued that for an aluminium smelter to leave the UK and go to another country would not make much difference to climate change.
But it would make a "huge difference" to those who lost their jobs as a result, he said.
Energy companies claim that green taxes are to blame for around 10% of the average household's energy bill.
Energy Minister Michael Fallon is understood to be looking at ways to reduce the impact of environmental measures have on household energy bills, The Times reported.
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There is nervousness, anxiety and on the streets of Edinburgh fuelled by an atmosphere unlike anything seen before in recent UK politics.
How will the vote go? What would a Yes victory do to England? Policital Editor Tom Bradby answers readers' questions on the referendum.