Not content with just banning porn and plastic straws, Theresa May has decided to add a £1 trillion – that’s £1,000,000,000,000 – economic black hole to her “legacy” with her new policy to force the UK to have ‘net zero’ emissions by 2050. Philip Hammond has already warned that the cost “is likely to be well in excess of a trillion pounds”. Blows the row over tax cuts into insignificance…

The problem is that no-one has any idea how much it is actually going to cost. The Climate Change Committee (CCC), chaired by scandal-ridden Lord Deben, has put out a figure of £50 billion every year. BEIS’ preliminary estimate puts the cost a full 40% higher at £70 billion per year – these are just back of the envelope calculations. The Treasury wants to do a formal review of the costs but this will take months, not days. The fact that an outgoing Prime Minister is trying to bind the country with a commitment this vast without even doing a proper costing first is the height of irresponsibility…

Worse, a huge proportion of the costs won’t fall on the Treasury itself but directly on ordinary people. The plan laid out by the CCC relies heavily on expensive changes in consumer behaviour. Energy bills will rise, drivers will be expected to switch to more expensive green cars. This is fine for people like John Gummer who’ve had their snouts in the trough for years. For a pensioner struggling to get through the winter or someone who depends on a van to run their small business, these changes will be very costly indeed…

Businesses will also bear a huge part of the cost – it will effectively spell the death knell for serious manufacturing in the UK. Businesses will simply move their factories, emissions – and jobs – overseas at an even greater rate. May’s Government has already done a great job helping to drive car manufacturing out of the country with their ban on new petrol cars from 2040. May’s latest genius idea should finish the job…

Whitehall insiders are laying the blame squarely at the door of May and her dour Business Secretary Greg Clark, who have been gripped with a desperate desire to rush through something to give them some semblance of a legacy in their last six weeks in office. If May wants to leave a responsible legacy behind for her successor, she won’t lumber them with one of the most costly and damaging policies in the history of the UK…