The brightest and the best gravitate towards where the power really lies in Whitehall. I’ve never subscribed to these views before, as I found those in the old Department for International Development to be the best, but I do wonder whether it is now true. Are the Treasury playing a canny game when it comes to net zero?

It is well documented that Treasury officials had been sceptical of insulation measures, especially the benefits of solid wall insulation compared to the risks and costs. They were right. Last year, the National Audit Office were damning over the solid wall insulation fitted under the ECO4 scheme. Following this, the Public Accounts Committee were scathing over the poor management shown by civil servants in DESNZ and they demanded criminal action is taken against some of the firms involved.

I suspect Treasury officials are quietly questioning other net zero policies championed by DESNZ. One policy in question is the Boiler Upgrade Scheme, which subsidises heat pump installations to the tune of £7500. The overall budget since the scheme started passed the half a billion £s barrier some time ago and you will have read my concerns over the societal fairness of the policy. What hasn’t been highlighted so far, is that any budget underspend by DESNZ goes straight back to the Treasury.

Now when the sums are in the tens of millions, it might not matter. But the Warm Homes Plan envisages nearly £3 billion more being spent by 2030, based on installation volumes increasing at rates of up to 50% year-on-year. Now that is beyond optimism. So why did the Treasury approve the spending levels?

Partly rhetorical question I admit. Do they know or at least suspect, that these volumes will not materialise and when they don’t the cash comes back to them for “better” ways of using resources – like defence, health, schools or pre-election tax cuts? They get the headline of being green, recoup some of the cash through prudence and then get to spend it again for more headlines. Maybe the smart ones do work in the Treasury.