"Enough is enough", energy minister John Hayes proclaimed last week as he propelled himself into the headlines and a full-blown war of words over the future of British wind power. But unhelpful as his intervention was, his very public tussle with the Energy Secretary, Ed Davey, was a mere sideshow compared to murky dealings over energy policy going on behind closed doors in Whitehall, with the ministerial "quad" – David Cameron, Nick Clegg, George Osborne and Danny Alexander – expected to meet again soon.

This anti-wind rhetoric obscures another government agenda: a new dash for gas that will keep Britain hooked on expensive foreign imports and do nothing to tackle high fuel bills. This week, Friends of the Earth revealed that the coalition is preparing to write a blank cheque for the gas industry to build new gas plants. Outrageously, it’s exempting back-up gas power stations from the Levy Control Framework, a set of Treasury rules which restrict public spending on energy. The result is likely to be a huge rash of investment in gas, funded by taxpayers, which could see more gas power stations being built than are needed.

Friends of the Earth accepts that we need some gas as a back up while the UK makes the shift from fossil fuels to renewable energy, and this includes a small amount of unabated gas – without Carbon Capture and Storage – to be maintained as back-up capacity. But pledging unlimited sums of public cash for this end is madness. In effect, you and I could end up paying for gas power plants that, if run at full whack, risk busting our targets to tackle climate change. In fact, we could end up paying for them not to run at all, when the penny finally drops that too many have been consented, and all we’re left with is stranded assets.

So why are they doing it? The Treasury has pressed hard for these gas power stations to be exempt from the rules, and the Department of Energy and Climate Change (DECC) appears to have conceded without a fight. Nervous ministers may be listening to scare-mongering about renewable energy making the lights go out. But I suspect it has a lot more to do with the Chancellor, hell-bent on moving the government away from its green commitments at any cost to the economy, against the wishes of senior politicians and business including the CBI.

Let’s not forget the long string of free lunches that Osborne has handed to the gas industry over the past year. First came the announcement from the Energy Secretary in March that made green groups despair: "we can’t take our foot off the gas for some time yet". Davey was allowing new gas plants to pump out carbon at 450gCO₂/kWh until 2045, which, given most modern gas plants emit just under 400g, was effectively a free permit to pollute for the next three decades.

I strongly suspect the decision was made by a novice minister under pressure from Osborne, without enough briefing from civil servants. It was accompanied by a pledge to develop a Gas Strategy, the rationale for which officials have privately conceded to be ‘because the gas industry felt left out’.

Then, in July, came news of a leaked letter to from the Chancellor to Davey, demanding the government issue "a statement which gives a clear, strong signal that we regard unabated gas as able to play a core part of our electricity generation to at least 2030". Cue a dutifully trotted out press release from DECC, the wording of which appeared to be practically lifted from Osborne’s letter. A few days later, the Chancellor’s father-in-law Lord Howell was exposed as an influential oil and gas lobbyist. The pieces of the jigsaw were slowly falling into place.

September saw more tax breaks for North Sea oil and gas, and an announcement that Osborne would consult over a new tax regime for shale. Then came Davey’s assurances to the gas industry in October that he expects 20GW of new gas to be built between now and 2030 – completely at odds with the Committee on Climate Change, which sees just 6.5GW of new gas by the same date.

It’s not hard to see who’s pulling the Energy Secretary’s strings. Taken together, these concessions add up to a covert strategy of support for gas by a Chancellor who appears in hock to the fossil fuel industry, whose economic calculations are frighteningly short-termist, and who sees green policies as a burden instead of an opportunity for growth.

The Treasury is lobbying hard to restrict future investment in clean energy through the upcoming Energy Bill, expected in Parliament this month. This is a once-in-a-generation opportunity to change the way we source our power for the next 20 years – and our booming green economy is at stake, which now accounts for almost a million jobs.

Enough is enough. It’s time for Cameron to stop the dash for gas in its tracks and urgently lay down a clear pathway for clean British energy.

Guy Shrubsole is energy campaigner at Friends of the Earth