RENEWABLE fuels company D1 Oils is putting its product to the ultimate test by entering a "green" car into the 24-hour Le Mans race in France.

Yesterday, the Stockton company unveiled its D1 Lola B2K car, which runs on a blend of vegetable oil and diesel.

It will compete against high-performance sports cars in June if it passes tests and qualifies over the next five months.

The car is believed to be the first biodiesel-powered race car.

D1 Oils has developed its blend of biodiesel with seeds from the jatropha shrub - a South American weed traditionally used as a laxative.

D1 is growing jatropha, which can grow in dry conditions on wasteland, on its plantations across Africa, India and East Asia.

Jatropha oil will fuel a modified Volkswagen Touareg engine, which is undergoing safety tests in Maldon, Essex.

A D1 spokesman said: ''We think our fuel has a lot of advantages. Ordinary diesel tanks can go 25 per cent further than petrol ones and ours is pretty much the same.

"We have to get through the tests, but we hope to be the first biodiesel-powered car to race in Le Mans."

The first track test will take place at Snetterton race track, in Norfolk, in the next two weeks, before team groupBio faces the first Le Mans trial in Sebring, Florida, next March.

The blue and yellow car will be raced by Norfolk groupBio, led by Ian Dawson, an experienced Le Mans competitor.

It has a top speed of 200mph, compared to most petrol competitors' 215mph, but the team hopes that, being a diesel, it will travel further before needing a refill.

D1 chief executive Philip Wood said apart from winning the coveted Le Mans gold trophy, the team's other objective was to test the performance, fuel efficiency and emissions produced by different biodiesel blends during the trials.

''This is about demonstrating that low emissions don't mean low performance," he said.

''It is going to be of immense value to motorists who want to know that biodiesel will get them the mileage and performance they need while contributing less to global warming.''