A truck rescued from the scrap heap and restored in Dorset is about to complete a round-the-world journey - powered by waste vegetable oil.
Andy Pag, 36, of Croydon, London, began his journey in September 2009.
He restored the vehicle in Fontmell Magna, Dorset using reclaimed materials after rescuing the 22-year-old school bus from a scrap dealer.
It has travelled 30,000km (18,600 miles), passed through 25 countries and returns to the UK on Friday.
And as well as helping to highlight an environmentally-friendly way of travelling, Mr Pag has also found love - after falling for an American journalist who was writing about his journey.
She has now joined him on the trip, which is due to be completed on Friday when the couple arrive in the UK.
The vehicle has a 1,200 litre fuel tank and oil filtering system, and was converted to run on vegetable oil by Oilybits of Hartgrove, Shaftesbury.
The truck usually travels 5,000km (3,100 miles) on a full tank of fuel.
Mr Pag says travelling around the world using waste vegetable oil has convinced him tackling "consumption-culture" is the key to reducing carbon emissions.
Finding vegetable oil thrown away by restaurants along the route has been one of the main challenges of the trip.
Mr Pag said: "The trickiest areas to find vegetable oil were in Asia, Pakistan and India.
"They don't tend to fry much food in these places and whatever oil they do use they reuse, time and time again.
"In the US vegetable oil is highly valued because they use it as animal feed, so again it was tricky to get hold of fuel here.
"At times like this I used biofuel from companies that collect vegetable oil for this purpose, instead of going to the restaurants.
"In India I found a man who extracts a muddy-type of vegetable oil from the ground, which is found there after harvest time.
"But most of the time I just made sure the tank was full before I arrived in areas where I knew I would struggle."
The Mercedes truck has also suffered "constant breakdowns" and last year Mr Pag was arrested for using a satellite phone illegally in Ajmer, India.
He was fined 1,000 rupees (about £15) by a court for violating Indian wireless and telegraphy laws.
The court dropped a more serious charge of misuse of a satellite phone for espionage and terrorist activity.
"This held up the trip for months", Mr Pag said.
Halfway through the tour across Europe, the Middle East, Asia and the Americas, Mr Pag met freelance journalist Christina Ammon, 36, from Oregon in the US.
The couple fell in love and Miss Ammon joined Mr Pag on the second half of the truck's journey.
Mr Pag said: "She contacted me when I was in Nepal because she wanted to write an article about the truck.
"We kept in touch after that because we have a lot in common - she lives in a truck and we both like paragliding.
"Eventually I said to her: 'It's a shame you're not a bit nearer because I'd really like to take you out to dinner'.
"She said: 'Well when are you arriving in the US?'
"I was due to arrive in the US around Valentine's Day and promised to take her out on a date.
"In the end we couldn't wait until then and she ended up joining me early in Indonesia and the relationship blossomed from there."
Miss Ammon says the best bits of the trip have been the breakdowns.
She said: "That's when we met the most interesting, friendly people and had the unique sort of adventures and insights which you can't have travelling any other way."
Mr Pag added: "We couldn't have done it without the enthusiasm and help from the strangers we've met along the road.
"The random acts of kindness have given us an overwhelming faith in how great humankind is.
"I'm as surprised as anyone that we got around the world without putting any fossil fuel in the tank."
The truck, along with Mr Pag and Miss Ammon, is currently in Belgium and will arrive in Dover on Friday.
In 2007 Mr Pag drove a chocolate powered lorry to Timbuktu, using biodiesel made from factory-waste cocoa butter.