Every few weeks Gordon Elliott drives 22 miles to the Hare and Hounds pub in Marple, Cheshire, collects a barrel of waste cooking oil from his stepdaughter and takes it back to his personal oil refinery in his garage in Leigh, near Bolton. The retired construction site manager then decants the liquid into a machine and adds a few chemicals.

Twenty-four hours later the waste oil has been purified, filtered and refined and is ready to be used in one of his family's two diesel cars. Instead of paying £1.25p a litre at the local supermarket, he has paid 15p to make his own biodiesel. He says he is saving nearly £100 a month - as well as 90% of the greenhouse gases he would normally emit from driving. The cars perform perfectly, the equipment will be paid for within a year and the pleasure of making his own fuel is intense. "It's the principle. I do it for the environment and to spite the exchequer," he said.

Elliott, 79, is part of a cottage industry of people who have turned to making their own recycled "biodiesel" in response to the doubling of fuel prices in just over a year. Companies making biodiesel "reactors" report booming sales and demand for cheaper diesel is outstripping anything they can produce.