Swiss teacher Louis Palmer has returned home ecstatic after an 18-month tour through 38 countries in a taxi run on solar power.
Plagued by snow, ice and a broken windscreen wiper, the final days of the 53,451 kilometre tour were a chilly challenge for Palmer and his "Solartaxi" team.
Despite the difficult conditions, Palmer was a mere 25 minutes late for his homecoming party at the D4 Technopark in Root in canton Lucerne - not bad considering the length of the trip and a busy schedule that included stops at world climate conferences in Bali and Poland.
"It's an unbelievable feeling to be back – this is so exciting! I didn't expect so many people to be here," said Palmer as he thanked the crowd of adults and schoolchildren gathered at the balloon-festooned finish line.
His former babysitter, Elisabeth Odermatt, was carrying an additional bunch of balloons for Palmer, including one in the form of a globe.
"This was his dream as a boy – to travel around the world in a solar-powered car," she told swissinfo.
Spreading the word
Root secondary school teacher Peter Gürber used Palmer's adventure to teach his students about geography and renewable energy.
"It's a great experience for the students," said Gürber, who deemed the homecoming worthy of a class field trip.
Palmer, who is also a teacher, said educating the public about solar energy was the main goal of his journey. With a maximum speed of 90km/hour, he logged an average of 100 kilometres a day.
"I could have made the trip in less time," said Palmer, "but I wanted people to learn about it."
By his calculations, up to 600 million people have gotten the message thanks to the press; that's around a tenth of the global population. In China alone there were 650 media reports on the Solartaxi.
In good company
Designed by Switzerland's two federal institutes of technology in cooperation with private partners, the vechile consists of a solar vehicle and trailer with solar cells.
Over the course of the journey, Palmer welcomed about 1,000 passengers aboard including politicians, celebrities, honeymooners and hitchhikers.
When asked who had been the most memorable, Palmer quickly answered: "That would have to have been Ban Ki-moon, secretary-general of the United Nations. I drove him to work in New York one morning!"
Once bomb sniffer dogs had declared the vehicle safe, the Solartaxi received a police escort complete with flashing blue lights to the UN building .
But that wasn't the Solartaxi's first guarded trip – Syrian and Saudi Arabian police also provided protection along the way. In India, a friendly motorcycle gang volunteered to help Palmer navigate the chaotic streets.
Other famous guests included Prince Albert of Monaco and United States comedian Jay Leno. Palmer's last official passenger was Lucerne parliamentarian Max Pfister.
"It's not just a car that moved around the world – it's also a car that moved the world," Pfister remarked.
The overwhelmingly positive response to his vehicle has left a lasting impression on Palmer.
"Even a Hummer driver gave me the thumbs-up sign," he said, adding that he had been surprised at people's awareness of global warming wherever he went.
Although his Solartaxi does not have any heating, it looks like Palmer's concept will remain a hot topic as the demand for sustainable energy increases.
"I believe in 100 per cent solar," he concluded.
swissinfo, Susan Vogel-Misicka in Root
The Solartaxi, designed by Switzerland's two federal institutes of technology in cooperation with private partners, consists of a solar vehicle and trailer with solar cells.
It is powered totally by solar energy: 50 per cent of the energy comes from the solar cells on the trailer; the other 50 per cent is produced and fed into the power grid on the roof of the Swisscom building just outside Bern and accessed via power sockets en route.
The Solartaxi, which has a maximum speed of 90km/h, thus uses electricity from 100 per cent renewable energy and releases no emissions into the atmosphere. It was accompanied by a conventional vehicle carrying everything needed for a trip around the world.
In 1990 a solar-powered car designed by Biel's engineering school won the World Solar Challenge across Australia.
In May 2007 the Sun21 boat successfully completed a trans-Atlantic crossing.
In 2009 a 30-metre boat known as Planet solar will try to circumnavigate the globe.
In 2011 Swiss adventurer Bertrand Piccard hopes his Solar Impulse aircraft will fly around the world.
In the Intergovernmental Panel on Climate Change report in February 2007, scientists said it was "very likely" - or more than 90% probable - that global warming was man-made.
The report predicts a "best estimate" that temperatures will rise by 1.8-4°C in the 21st century, within a likely range from 1.1-6.4°C.
The study projects a rise in sea levels of 28-43cm in the 21st century - and said bigger gains could not be ruled out if ice sheets in Antarctica and Greenland thaw.