Solar-Powered Car Sets New World Speed Record

The Sunswift IV University of New South Wales

A new champion amongst solar-powered cars has emerged in sunny Australia: A student-built solar car, christened the Sunswift IV, has crushed the previous speed record with a run that topped out at 56.85 mph.

Built by students at the University of New South Wales, the Sunswift IV known as IVy, though the pronunciation is a mystery was designed specifically to break the existing speed record of 49.09 mph, set by the GM Sunraycer way back in 1987. That required removing the IVy's 55-pound battery that's typically included to assist with longer trips, which threw off the car's balance a bit. But the reduced weight apparently helped, since the car managed an average of 55.14 mph in two trips (going in opposite directions) on a 2,500-meter track.

The record is peculiar because it can only be awarded to cars powered solely by the sun--no batteries can be involved , which is why the previous record stood so long (and why the actual speeds are not that fast). It also means that the cars themselves have to be ridiculously energy-efficient--even the Sunswift team admits that only a "very small person" can fit into the cockpit of the IVy.

The IVy is eventually due for the World Solar Challenge this October, where the team hopes to go even faster: Apparently, on the day the record was broken, the skies were mostly cloudy, so the team has a lot of confidence that they'll be able to raise the record again when racing in full sunlight.

Executive Summary

Sunswift has broken the Guiness World Land-Speed record for a solar-powered vehicle. The record was set at 88km/h by Sunswift IVy on the 7th of January, 2011. The previous record was set by General Motors Sunraycer, which travelled 78km/h on roughly 1500 Watts.
During the day that Sunwift IVy set the record, conditions were mostly cloudy. The record breaking run was at 10:30 AM when we got lucky with enough of a break in the clouds. Solar-noon was at 13:06 that day. The car used about 1050 W to travel at the speed it did for the record run. The batteries were removed, so as to compete on the grounds of energy efficiency alone - i.e. not how big your batteries are.
This means that Sunswift IV, with ~25% less power than the previous record holder, went 13% faster. We've come a long way since 1988.
The maximum power we ever saw from the solar array was 1340 W. The clouds never stayed away for long enough to complete any faster runs.