Both outlined the dangers of global warming, both said they were committed to reducing greenhouse gas emissions, both called for the U.S to join the Kyoto agreement, and both called for a diverse renewable energy sector. However, neither gave any specific targets or details of how and when this will happen.

Mr Blair said that climate change would top the agenda for the UK G8 presidency next year and that he would seek agreement on how to speed up the science, technology and other measures necessary to meet the threat.

Michael Howard gave his address at the environment forum hosted by Green Alliance and ERM consultants on Monday, saying he was “making the case for new leadership in the way we manage our environment.”

Both leaders also acknowledged that transport was a major contributor to emissions levels, with aviation emissions set to double by 2020, and that they would like to see aviation brought into the EU emissions trading scheme in the next phase of its development.

Mr Howard highlighted past Conservative achievements such as the Clean Air Acts, the ban on CFCs, landfill tax and home energy and conservation act, and pointed to the fact that the party is making its new headquarters, in Victoria Street, carbon neutral.

He said the Conservatives had shown how the market can be used to deliver environmental ends and said emissions trading was the next step: “It will give business the incentive to find the most cost effective route to reduced emissions and to make proper financial provision for the emissions it cannot yet reduce.”

“The promotion of carbon trading will be a major objective for the next Conservative government. But to be effective it must be rigorously policed and must be built on a level playing field, with a consistent carbon value across all participants so that no nation’s industry can claim to be at a competitive disadvantage,” he said.

He criticised the government’s reliance on wind energy as the major renewable source for the near future (see related story) and said Britain was losing out on the potential benefits of biomass, solar, wave and tidal power.

When it comes to energy, though, Mr Howard said that home energy efficiency is the area where we can make most progress. He suggested removing stamp duty at point of purchase from homes with certified energy efficiency measures already in place. For those where upgrades still need to be made, the new homeowner could make the improvements and then claim a rebate on the stamp duty they have paid.

In addition, Mr Howard suggested simplifying the current building regulations that relate specifically to energy efficiency standards and perhaps replacing them with one simple thermal target.

He also said the next Conservative government would give an extra boost to combined heat and power (CHP) and criticised the government for missing CHP production targets, as well as the new electricity trading arrangements that put CHP producers at a disadvantage.

Tony Blair also addressed these issues at a speech to the Prince of Wales’ Business and the Environment Programme the following evening. He largely made the same points as Mr Howard, but highlighted the fact that Britain is on track to meet its Kyoto target, and has seen the economy grow by 36% since 1990, while emissions fell by 15%.

Mr Howard had said the Conservatives should take credit for the drop in emissions through its “dash for gas” policies in the 1990s.

Mr Blair continued that he would like to see other renewable energy forms expanded but that wind would still form the primary source of renewable production in the short term.

Neither Blair nor Howard ruled out the possibility of nuclear power making a comeback in the future, but both said that there were currently no plans to expand its use at present.

Like the Conservative leader, the Prime Minister outlined energy efficiency in buildings as a major source of emissions reduction. To this end he said that all new schools and City Academies would be models for sustainable development and subject to new regulations for energy saving.

It was unclear, however, whether these regulations were in place for the school buildings currently under construction, or whether these rules would only apply to future projects.

Similarly, Mr Blair said that the energy performance for new buildings would be raised by 25% next year, and that government would work with the construction industry to encourage a new flexible code for sustainable buildings.

Both speeches were welcomed by environment groups. Referring to Mr Blair’s speech, Barbara Young, chief executive of the Environment Agency said: “This was a very positive speech. We are very glad he has given his personal backing to more renewables, to tackling emissions from aviation, and making our housing more environmentally friendly.”

Tony Juniper, Friends of the Earth director, said: “These are some of the most sensible comments on the environment from a Conservative leader for many years. Michael Howard must now stand up to powerful lobbying from industry and the motoring lobby and help persuade Tony Blair to take the tough decisions that are desperately needed, and support him if he makes them. Climate change is too important to be a political football.”

By David Hopkins

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