James Murray

Well, that was unexpected. Ever since their husky-hugging, vote-blue-to-go-green period ended with the unforgettable sight of leader David Cameron cycling to work followed by a car to carry his bags, the Conservatives have been largely quiet on environmental issues.

There have been occasional policy proposals, but the general feeling within Westminster was that Cameron had decided green was not a vote winner and was happy to offer bipartisan support for the government's climate change bill and the UK's efforts ahead of Copenhagen while looking for more promising electoral battlegrounds.

Whispers from Whitehall and the green business community had even begun to suggest that Cameron had largely ditched his early green ideals, with senior civil servants and business leaders warning in private that Tory opposition to the Infrastructure Planning Commission and plans to cull the number of quangos would only serve to damage the low-carbon transition.

All that changed this week, with the unveiling of several environmental proposals that in many ways read like a green business wish list.

George Osborne's speech today at Imperial College was not far short of a master class in political positioning, responding to the legitimate complaints made by those within the environmental movement and proposing policies that, on the face of it, offer appealing solutions.

People don't like bin taxes and being ordered by councils to recycle. Osborne promises to roll out an incentive scheme that pays people to recycle and has already proved successful in trials.

Businesses get confused by the sheer number of low-carbon funds, accelerators and incentive schemes. Osborne promises to set up a single green infrastructure bank to provide them with simple access to finance.

People don't think the government is doing enough to tackle its own carbon emissions. Osborne promises to get every department to report on its energy use and sign up to the 10:10 campaign to cut emissions by 10 per cent within a year of taking office.

Low-carbon businesses can't raise capital in the current investment climate. Osborne pledges to launch green ISAs to help individuals save, while supporting green firms.

It is a classic outflanking manoeuvre and shameless play for traditional Labour voters and what's more, the government has no one but itself to blame. The strongest part of Osborne's speech – and the part that will resonate the most with frustrated green business leaders – was the section accusing the Treasury of undermining the UK's low-carbon plans. It is indeed a disgrace that in more than two years Alistair Darling has never given a speech on the environment, just as it is a disgrace that it is an open secret that the Treasury has put the kibosh on any number of innovative green policy proposals over the past 13 years – all it took was for Osborne to point out the uncomfortable truths.

Add in the commitment to scrap Heathrow's third runway, invest in high-speed rail and roll out a new programme for green home makeovers, and the Conservatives have a pretty strong environmental package for the election. And yet, as with the wider pre-electoral landscape, there is a sense that these Conservative policies will not quite seal the deal with green voters and green business voters in particular.

Each of the new policies are carefully structured to fit into Cameron's world view of small government letting the private sector do the heavy lifting. But while many of them are impressive and sensible reforms, there is also a sense that these policies alone will never deliver the deep emission cuts that are required.

Explicitly laying down the battle lines that will define next year's election, energy and climate change secretary Ed Miliband was quick to point out that the Conservatives' new proposals are largely uncosted, adding that it was the Tories who opposed the government's economic stimulus plan, including £400m for low-carbon industries.

The Conservatives' credibility on environmental issues rests squarely on the shadow cabinet's ability to square the circle of green initiatives and funding. Individual policies look good on paper, but can they really deliver deep cuts in emissions while proposing rapid cuts in public spending? Can the government slash emissions 10 per cent in one year when Cameron and Osborne openly admit the money for investing in energy-efficiency improvements is simply not available? Green ISAs are great, but will they and other financing ideas really raise the cash needed for the development of high-speed rail and the decarbonisation of our energy infrastructure?

Add to this rumours that the Environment Agency and others could get caught up in Cameron's pledge to slash the number of quangos, the shadow business secretary Ken Clarke's stated opposition to onshore wind farms, and the fact the Tory backbenches are home to Parliament's only climate sceptics, and it becomes clear why doubts over the Conservatives' green strategy refuse to go away.

As with the wider political landscape at the moment, the Conservatives' environmental policies are well thought out and have the air of a party preparing for power, but they again fail to create the impression that David Cameron is home and hosed ahead of next year's election.