Oxford City Council is launching a campaign to cut its carbon emissions by a quarter.

In the year 2005-6, which is being used as a benchmark for the scheme, the authority emitted about 10,000 tonnes of carbon dioxide — enough to fill 350 million party balloons.

The council plans to cut emissions to 7,500 tonnes by 2010-11 — and then by a further three per cent every year after that, as part of its Getting Our House in Order scheme.

Assistant sustainable energy officer Charlie Morris-Marsham said: "The council, and Oxford as a whole, is only a small contributor to global climate change. But initiatives such as Getting Our House in Order have a big role to play in increasing awareness about energy and climate change both inside and outside of the council."

The Town Hall has used things such as fuel consumption for vehicles, utility costs and waste generated in council offices to work out its carbon emissions. As part of the scheme the council is planning a number of projects, including several to reduce emissions at leisure centres.

John Tanner, the council's executive member for a cleaner, greener city, said: "The projects highlighted in Getting our House in Order are a great way to help the environment and save taxpayers money.

"Leisure centres have already set up an energy champion network, where staff monitor and reduce their own energy use.

"Energy-saving pool covers were installed earlier this year and the council is already reaping the benefits."

Last week, the council was presented with an award by the Carbon Trust for reducing its emissions and Mr Tanner said the initiative would build on this success.

Bob Timbs, the executive member for leisure and sport, said: "Keeping an eye on the energy we use in our leisure centres not only saves money, it makes our facilities more sustainable and it helps to protect the climate for future generations."