Swiss school teacher Louis Palmer has welcomed all sorts into the passenger seat of his aptly named Solar Taxi.

Last week the distinctive machine pulled into Cooma for one of hundreds of pit stops it will make during a 40,000km journey around the world to promote a petrol-free mode of transport.

"I've travelled the world on bicycle, ultra light aircraft and by car," said Mr Palmer.

"While people have been discussing if global warming exists or not I've actually seen it present across the world.

"It was because of this I asked myself what could I do to help make people aware, which gave me the idea to build a (clean energy) car.

"So I threw out my television and spent two hours every evening working on the car, which got support from four Swiss universities and the United Nations."

Mr Palmer began work on the car, which can drive 300km using battery power, in 2004.

After a year of building and a year of testing it ran like a Swiss clock, according to Mr Palmer.

"It doesn't need any solar cells as energy can be taken from panels on a house roof to charge the battery," he said.

"On July 3 2007 I started the trip which led me from Switzerland to Germany and across to Turkey and Jordan.

"We had to wait at Jordan's border for three weeks as we didn't know if Saudi Arabia would issue a visa, but the King eventually let us through with a police escort.

"From there I went to Dubai and then India for the International Convention on Climate Change."

Mr Palmer was almost halfway through his journey when he pulled into Cooma on Thursday.

While in town he criticised the lack of research and development of renewable energy technology in Australia, pointing to the country's abundant renewable energy resources.

"It surprises me there is so much sunshine but compared to other countries there's nothing by way of renewable technology, like wind turbines and solar cells on roofs," he said.

"Australia, which still uses coal, is behind the rest of the world as it has so much sunshine here, but it has been ignored for the last 10 yrs.

"Now it's time to catch up."

So far 400 people have travelled in the taxi.

Mr Palmer will leave Australia in March after attending events in Adelaide and Perth.