Palmer, who touched down at UN climate change talks in Poznan, Poland, said the feat proved that solar power was a viable alternative to carbon-based fuel sources. Though to do what Palmer did, you'd need to drive a tiny three-wheeler tugging along a solar array almost as big as the car itself.

While the car probably needs a major redesign (and perhaps some more solar panel breakthroughs) to even inch close to becoming a regular on highways, it did disclose some promising technology. The car reached 55mph speeds and could travel for 300km on a single charge. Through the 17 months on almost non-stop driving, it only broke down twice.

Though this car's adventure is over, Palmer's not ready to give up eco-driving yet. He's planning a trip with six vehicles around the world in 80 days (ha!) that would draw power from hydro, geothermal and wind energy. [BBC]

The Solar Taxi gets its juice from a $5,000 solar panel trailer provided by German company Q-Cells. Weather permitting, the trailer provides the Taxi with 60 miles of oompf. Longer runs are powered by a pair of $15,000 250-lb. recyclable batteries from Zebra Battery. They store energy from the sun and from whatever electrical socket Palmer can find at night (it's just like searching for a socket at a conference, but bigger, and people will still manage to trip awkwardly over the cord).

Altogether, Palmer said the rig gets about a 200 mile range between charges. As of this weekend, Palmer and his crew had traveled 27,000 miles across 28 countries, so that's a lot of stop and go driving—or is that charging?

The trip is scheduled to conclude in December, but Palmer won't be finished just yet. He's also in the middle of planning an 80-day solar powered race around the world for sometime in 2009. [ABC News]