Delegates at a key climate change summit feeling guilty about exhaust-spewing taxis have another solution -- call a solar taxi that has travelled over land to Asia all the way from Switzerland.
Cheery Swiss national Louis Palmer fulfilled a childhood dream when he set off from his home country on July 3, travelling over desert, city and sea in 17 countries to reach the conference in Bali, Indonesia.
"In 1986, I was a 14-year-old boy, I was dreaming that when I will be an adult, I want to drive around the world," he told AFP.
"Then it came to my mind, how can I travel around the world and enjoy the beauty of this world with a car that is polluting the world? Then I thought the perfect car would be a solar car."
His car, which has become a major attraction at the gates of the summit of some 188 nations, was built in three years with scientific help from four universities and 15 Swiss companies.
The car pulls a trailer with six squares metres (64 square feet) of solar panels which soak up the sun. The electricity is fed into the battery which powers the car, and can run for up to 100 kilometres (62 miles) a day.
Surplus electricity created by panels back at base in Switzerland is also fed back into the grid, so when Palmer travels by night or on a cloudy day, he can plug into the electricity supply and withdraw his earlier deposits.
"It's the first time in history that a car is driving around the world without a single drop of petrol," boasted Palmer, a teacher by training.
His epic solar journey is not his first adventure -- he traversed Africa on a bicycle and North America in a light aircraft.
Getting to Bali, however, has thrown up its own challenges. Traffic conditions in India were a nightmare, he said, while Saudi Arabia insisted on a police escort as he made his way across the desert.
So far, Palmer has gone by land through Europe and the Middle East, then by sea to India and on to Indonesia.
In one year from now, after traversing much of Asia, Australia, North America and Africa, he will return to Switzerland to try and drum up support for the commercial possibilities of solar cars.
For the moment, he has his hands full, with more curious customers waiting to take a ride in his unique automobile which, he said, "works like a Swiss clock."