Tory campaigners on climate change are embarking on a fightback against sceptics on the right of the party who have tried to "smother" debate in recent months, according to party sources.

On the eve of a damning judgment by the Green Alliance on the Tories' record in government, Conservatives alarmed by the threat of climate change are pledging that they will not be "rolled over" by sceptics.

But the green Tories acknowledge that as they move on from the era when David Cameron rode with huskies on a visit to a Norwegian glacier in 2006, they need to recalibrate their message to respond to consumers struggling with rising energy bills. "People don't want the green economy to live in a bubble," one source said.

A first step in the fightback is being taken by Greg Barker, the climate change minister, who writes in a Guardian article that the government will help drive down energy costs by prising open the energy market to challenge the "big six" suppliers. "The big six need to become the big 60,000," Barker writes.

"This is a vision that happily unites the drive to get a better deal for hard-pressed consumers with ambitions for a greener, more local energy sector. To achieve this we need a new generation of energy entrepreneurs and disruptive, local new entrants."

But signalling new sensitivities among green Tories, Barker says alternative technologies such as offshore wind and new nuclear power stations are important but "not the entire recipe". The minister says environmentalists should stop seeing gas as the "bogeyman" and should instead focus on unabated coal.

"There is a lesson here for the environmental lobby. Gas is not a bogeyman. If used to the highest environmental standards, gas can be our ally," he writes. "If we are to scale up distributed energy and, crucially, at a time of a rising cost of living, ensure that energy bills are affordable, over the medium term in a way that is compatible with our climate targets, we will need more gas not less. Unabated coal should be the committed environmentalist's number one target, not the cleanest and most efficient of fossil fuels."

George Osborne raised questions about the Tories' commitment to the green agenda in his speech to the party's 2011 conference when he said the planet would not be saved by putting Britain "out of business". The chancellor announced that Britain would cut its carbon emissions "no slower but also no faster" than other EU countries.

The Tory green campaigners believe their plans should please Osborne because they fit with the party's traditions. They want to deregulate the energy market, in contrast to Labour which would, according to Barker, regulate the market even further.

Barker writes: "Conservatives are forging an agenda to encourage competition, innovation and greater consumer choice by attracting new entrants into the market, banking on more competition, diversity and choice to deliver a better deal for consumers."

But the campaigners are prepared to confront some figures in the party who used the Osborne speech to dismiss the need for action on climate change. They highlight an article by Tim Montgomerie, founding editor of the ConservativeHome website who is now comment editor of the Times, who called for the repeal of green energy laws.

Montgomerie wrote in July that he did not deny that the climate may be changing. But he added: "Britain's statute book is still creaking under the weight of yesteryear's laws and their commitments to invest in expensive green energies. Until those laws are repealed, British businesses and consumers will be paying a very high price for no earthly benefit."