A SHED, some old chip fat and some mechanical know-how are all helping one man to stay on the road.

Paul Shotton, a father-of-one from Upper Heyford, has halved his car's fuel bill after building a small biodiesel plant in his garden.

The 28-year-old decided to look into making the environmentally-friendly and cheap fuel - using waste vegetable and animal oil - when fuel prices rocketed in the summer of last year.

He said: "I decided to do it when I saw an article in a paper saying 'Petrol heads for a pound a litre'."

Armed with a book on How to make Biodiesel, Mr Shotton started spending the majority of his spare time tinkering in his shed.

He said: "I read the book, muddled through and made my own system, which produced some biodiesel."

Following some more advice from the book's authors, who run a small plant called Golden Fuels in Kingston Bagpuize, Mr Shotton is now producing fuel which costs just 45p per litre - after tax, raw materials and electricity - rather than paying more than 90p at the pump.

Mr Shotton said: "I am more than pleased that I have done it, though I'm not sure my girlfriend would agree.

"It has been a lot of long and cold nights out in the shed, but now that it is done I barely spend any time in there at all.

"I did have some concerns from the neighbours who thought I was going to blow up their caravan, but they were OK once I'd explained it.

"There are hazards involved because of the methanol and caustic soda used in the process, which you don't want on your skin. I wear goggles and do it in a well ventilated space. It's all common sense.

"Provided it is done in a sensible fashion and with a little bit of knowledge, there are no risks.

"Anybody who is mechanically capable and has a mind for engineering is capable of doing this at home. I'm a testament to that. I managed to do it just from reading the book."

Biodiesel, which is carbon neutral, has grown in popularity as an environmentally friendly alternative to mineral diesel, which contributes to global warming by releasing carbon into the atmosphere.

The alternative fuel is used widely in France, where it is sold at the pumps in a mineral-bio mix, and its fans claim it can be used in an ordinary diesel engine.

Although some vehicle manufacturers don't recommend its use, companies such as Peugeot and Citroen say a mix with 30 per cent biodiesel is OK and lorry-maker Scania supports the use of 100 per cent biodiesel.

The fuel is also slightly cheaper because the Government charges 20p less tax on every litre and, in his pre-budget report, Gordon Brown said that policy would continue.

For more information on biodiesel, how to make it and where to buy it, visit www.goldenfuels.com and, for a list of sellers across the country, visit www.biodieselfillingstations.co.uk