The Eden Project has taken delivery of a fleet of eco-friendly tractors after becoming the first place in the UK to trial the vehicles on 100 per cent EU-standard biodiesel.

Around half a million visitors a year make the trip from Eden's ticketing hall to the world-famous Biomes in land trains pulled by the tractors.

The newest additions to the project's vehicle line-up were unveiled today as part of the Sexy Green Car Show, the world's first eco-friendly motor show, which runs until April 15.

Two New Holland TSA115s will pull the land trains that transport visitors to the project from the top of the pit to the Biomes. Another TSA115 will be used by Eden's waste operations team and a smaller TC31 will be used by Eden's 40 gardeners.

The new machines will reduce carbon dioxide emissions by 70 per cent, carbon monoxide emissions by half, particulates (soot and aerosols emitted by diesel engines) by 70 per cent and hydrocarbons by 40 per cent compared with the tractors they replace.

Burning diesel produces greenhouse gases, such as carbon dioxide, which contribute to climate change. By using biodiesel, a fuel produced from crops such as rape seed and jatropha seed, a vehicle has a greatly reduced impact on the environment. This is because the plants the fuel is made from absorb amounts of carbon dioxide during their lives which greatly offset the emissions given when the diesel is burned. Also, conventional diesel is derived from limited supplies of crude oil while the plants biodiesel is produced from can be re-grown, making it a renewable energy source.

John Ryan, Eden's Transport Manager, said: "Since Eden opened six years ago we've had the ambition of running our tractor fleet on a clean, green fuel. We started trialling 20 per cent biodiesel in June last year and gradually upped the mix to 100 per cent. The land train and transport teams have worked really hard to make this happen and we're really proud of what we've achieved."

Eden's Gus Grand, the Producer of the Sexy Green Car Show, said: "The show has shown that loads of people are interested in green motoring and with these new tractors we're doing our best to drive that forward. If we can do it, so can others. The environmental benefits of the tractors are not solely due to the fuel either. The engines are more efficient than Eden's old tractors, contributing to the reduction in emissions, and they are significantly quieter too."

Eden's land trains cover roughly 12,000 miles each per year and the project used to run three, each with three carriages. Efficiency has now been improved by running two trains with four carriages each.