Solar cars turn 'toaster power' into high-speed adventure

Story highlights

  • Solar-powered car race from Darwin to Adelaide
  • Aim is to highlight the ultimate in renewable energy-efficiency
  • Teams from 21 countries compeiting in the 11th competition
  • Cars will reach speeds over 100kmph using same power that runs a toaster
Powered by the same energy produced by a toaster, this weekend 39 solar-powered cars are preparing to race across the Australian outback reaching speeds in excess of 100 kilometers per hour (62 miles per hour) along the way.
Setting off from Darwin on Saturday, many of the cars taking part in the biennial, 3,021-kilometer (1,877-mile) Veolia World Solar Challenge to Adelaide look more like ping-pong tables on wheels rather than conventional cars.
However, the spirit of adventure and quest for more energy efficiency is what drives the teams of volunteers, university students and organizers.
"We think about it in terms of the land-based version of ocean yacht racing," says Chris Selwood, the event director.
"Really it's about how much you can do with how little. We're looking for the ultimate efficiency in electric cars."
This year is the 11th race and Selwood is happy to point out that while most of the cars don't resemble anything else that will be rumbling down the Australian highways this weekend, some of the innovations pioneered by the vehicles over the years have made it into the mainstream.
Energy-efficient, "low-rolling resistance" tires that are on the market now were used by Michelin in World Solar Challenge events of the early 1990s, and since the inaugural event in 1987 the electric motors have improved in efficiency by at least 30%, says Selwood.
Some of the motors being used by teams have been engineered to work at 98% efficiency in turning electricity into motor power.
"That could drive a washing machine, ceiling fan or even electric vehicle," says Selwood. "There are many uses for a motor like that in our daily lives across a range of applications."
For the top teams, though, the aim is to get to Adelaide first and worry about the legacy of the technology later.
Nuon Solar Team's Nuna6 car is one of the favorites to win this year's competition.
As winners of the events from 2001 to 2007, Nuon Solar Team, made up of students from the Delft University of Technology in the Netherlands, hope to claim back the crown they lost in 2009 to Japan's Tokai University's team.
To aid their attempt, Nuna6 is made of a carbon fiber also used by some Formula 1 cars, making it 10% lighter than its predecessor in 2009.
And like Formula 1, strategy is expected to be important in giving each team the edge. Each team has to extract enough power from a battery with just 5 kilowatt hours of capacity (10% of the power competitors are anticipated to need to complete the race), while also judging when to charge it up for the next day.
"The biggest challenge is to drive non-stop, but we've got a good chance," says Nuon Solar Team's Nadine Rodewijk.
For others, making a solar car more appealing to the public is a greater priority than seeing the checkered flag first.
To highlight that solar cars are getting closer to the real thing, Bochum University in Germany's SolarWorldGT has shunned the sleek, aerodynamic design seen by Nuna6 and others in favor of something more recognizable with two doors and two seats.
That the SolarWorldGT can still effectively compete the race is thanks in part to improvements in solar and motor technology in recent years, and a new competition rule that has reduced the solar panel capacity allowed on each car by 25% compared to 2009.
"They've got to use that energy wisely to get up hills and get out from under clouds," says Selwood.
"By keeping some reins on some of these keys factors, we're seeing some very clever ways in addressing them."
But for all the goodwill and innovation on offer, when the rubber hits the road it will still be a race.
"Our aim as a team is to win," says Nadine Rodewijk from Nuon Solar Team. "Although personally, for each of us, it's about the experience and adventure, learning and preparing for the future."