Australia wins solar car challenge

17 Jun 2002

The winner of the 1999 World Solar Car Challenge is Aurora 101, made by a team from Australia's Aurora Vehicle Association. The car completed the 3010 kilometres from Darwin to Adelaide in Australia in six days at an average speed of more than 70 kilometres per hour.

In second place was Radiance, a car from Queen's University, Canada. Sunshark, from University of Queensland, Australia finished third.

Max Buneta, the manager of the team from Queen's University thinks that although solar powered cars reach average speeds of 80 or 90 kilometres per hour, the technology is unlikely to enter commercial vehicles.

"Even if we were to have 100% efficient solar cells (totally unrealistic), we would only get 8000 watts of power (for 8 square metre area). This is not generally enough to power even a small car. In order to minimise drag we have the driver lying on their back. If we made a comfortable seating position, we would lose a lot of power."

Most of the cars were powered by cells made from monocrystalline silicon, the standard material for commercial applications, which has an efficiency of about 20%. The price of solar cells increases dramatically for even the slightest gains in performance, so most teams are unable to afford cells with an efficiency of more than 20%. "In our case, we were very fortunate. SunPower decided to sponsor us with their 21% cells. If purchased at retail price, these cells would probably cost somewhere in the area of USD 1 million."

The rules of the race restrict each car to 8 square metres of solar cells and the sun shines an average of 1000 watts per square metre. This gives a theoretical power of 1680 watts to the Queen's car, although in practice this is a bit lower.

The solar cells are held on top of the car by a two-sided tape and is covered with a silicone based coating that is 98-99% optically transparent to prevent electrical shorts due to water or dust.

The highest placed gallium arsenide car, Cascade Cruiser, from Solar Motors, US, came in eleventh place.

SH