Ralph Waldo Emerson was probably thinking of politicians when he said that a foolish consistency is the hobgoblin of small minds. Ministers have to tack with the changing wind to reach their objectives – but there is a difference between inconsistency over time, and holding contradictory views now.

The current row between the coalition partners about energy bills and onshore wind is a case in point. George Osborne and the Conservatives have made a great play of trying to cut energy bills by axing the green levies that fund exactly the measures – energy-saving and cheap renewables – that will do most to protect households long term.

In theory, the cuts will save about £50 this year if fully passed on by the big six energy companies. That may or may not happen. Wholesale gas prices for delivery next winter have fallen nearly 15% in a year without obvious effect, and Ofgem has referred the big six to a full Competition and Markets Authority inquiry, precisely because of worries about the retail market. Meanwhile, the levy cuts have emasculated support for the green deal (loft lagging, cavity-wall insulation, better boilers and so on), and will mean we consume more energy in future than we would otherwise have done. That will make us more vulnerable to higher global gas prices.

Add to this bizarrely short-termist decision the desire of the Conservatives to put every possible obstacle – planning controls and subsidy cuts – in the way of onshore windfarms, which is being blocked thankfully by my successor, Ed Davey. David Cameron is now being urged to declare an onshore wind moratorium in the Tories' 2015 manifesto.

Of course wind turbines have opponents. I think I am the only participant on BBC Radio 4's Any Questions to have been booed by the normally courteous audience. But in a edition broadcast from Wotton-under-Edge in the Cotswolds, then in the fevered grip of a planning controversy over wind turbines, I said I thought they were beautiful.

All hell broke loose, and Jonathan Dimbleby attempted, in good journalistic fashion, to stoke up the furore by calling for a show of hands that he confidently assumed would lead to the minister's further embarrassment. In fact, the audience split about half in half. The protesters against onshore wind appear to be more noisy than numerous.

Everybody wants the convenience of electricity without the inconvenience of industrial kit anywhere near them. There is no energy source without venomous nimbies, but they are a minority. Onshore wind enjoys more than 60% support in polls, and offshore wind is even more popular (presumably because fish do not yet have the vote). But I even had a delegation of Conservative MPs complain about offshore wind turbines spoiling the sea vista from Bournemouth guest houses.

I stick to my view. Turbines are an elegant and minimalist solution to a pressing problem. Any design that combines such simplicity of form with such praiseworthy function is beautiful. They are a natural development of the largely man-made British landscape, once forested but now agricultural. When John Constable painted windmills, they were the turbines of their day, powering irrigation and milling grain. That, of course, is an aesthetic judgment, but what is not open to debate is the cheapness of the technology. Onshore wind is one of the two great renewable successes – the other being solar panels – where the EU's support has caused dramatic falls in cost. It is a triumphant example of successful industrial strategy creating cheap alternatives to fossil fuels.

The government is now slated to pay £95 per megawatt hour (MWh) to onshore wind producers, and it believes this will be the only renewable technology that may be cheaper than natural gas in 2020. It is already cheaper than gas in the right (windy) conditions: wind has beaten gas in more than half of all Brazilian energy auctions since 2011.

Given that we have an EU legal commitment, which the last Labour government agreed in 2009, to meet 15% of all our energy consumption from renewable sources by 2020, we should be installing as much onshore wind as we can. Every obstacle that boosts more expensive solutions will add to consumer costs: going offshore costs £155 per MWh or 63% more than onshore.

All turbines fail, and trip. Sorting them is cheap when you can drive up in a Land Rover, and expensive when you work from a rocking boat on a stormy night. In an attempt to cut these costs, offshore turbines are more expensive to engineer and protect against the elements. Moreover, the costs are not tumbling like solar and onshore wind.

To highlight the impact on consumer bills, imagine that the projected increase in offshore wind was in fact met by cheaper renewables. The British consumer could save up to £100 on their 2020 energy bills (which will already be higher because we will be consuming more energy thanks to efficiency cuts).

Conservative policy – cheaper bills by axing energy saving and pushing for luxury renewables – does not add up. It reminds me of the slogan for Stella Artois, the humdrum Belgian beer that positioned itself as a premium lager in the British market. It was "Reassuringly expensive". That at least was an honest description of the price, which we have not yet had from the Conservatives.