Wed Aug 27, 11:47 AM ET

ATHENS (AFP) - A group of Britons on Wednesday completed a 3,750-kilometre (2,330-mile) 'Grease to Greece' expedition in cars powered by vegetable oil in a bid to raise awareness about conserving fuel, organisers said.

Some of the nine cars were converted to run on purified vegetable oil while others had standard engines using biodiesel that was brewed overnight in a 'fuel pod' stored in a lorry accompanying the expedition.

Instead of filling up at petrol stations, the expedition's 'frybrid' cars ran on used frying oil donated by restaurants and cafes along the route.

"A lot of people don't realise that biodiesel, when made properly, will run in any diesel engine," noted expedition leader Andy Pag, 34, a webcasting specialist and trained engineer, who says he got the idea in a road trip from London to Capetown with his wife three years ago.

"We wanted to see if it's possible to do something with biofuels," he said.

"We had a lot of breakdowns (en route) but we managed to fix everything."

Setting off from London on August 16, the expedition crossed France, Belgium, Germany, Austria, Italy, Croatia, Bosnia, Montenegro, Albania and arrived in Athens on August 27.

On one occasion when the team was pulled over by German traffic police, their press cuttings proved more valuable than passports, noted Peg, who last year led an expedition to Timbuktu on a truck powered by chocolate soya oil.

His next project involves circumnavigating the globe with cars running on cooking oil and a small aircraft using an aviation fuel made from plastic bags.

"It's quite geeky, essentially it's like taking the molecules apart and building a new jigsaw with them to create fuel molecules," he told AFP.