The Sasol Solar Challenge, the race in which students from across the world race from Pretoria to Cape Town in solar-powered cars, kicks off this weekend.
The vast majority of the vehicles all follow a similar design: a sleek, flat frame with solar panels plastered on every nook and cranny to maximise efficiency.
But there is one vehicle that will stand out like a sore thumb: a small VW Beetle from the 70s outfitted with an electric motor.
One might think that the ZingBug from ZingCo would have a distinct advantage over the other cars, but that is exactly where you would be wrong. In ZingCo’s own words, it would be happy to simply finish the race.
Part of the reason the Beetle may not be competitive is that the solar cars created other teams can actually hit remarkable speeds. The Illanga II from the University of Johannesburg, can easily reach speeds of 200Km/h. For a Beetle from the 70s, at that speed the wheels would probably spin off. The Beetle is, of course, much heavier and needs a more powerful engine.
The 11-person team is led by Santa Scheepers, who was a finalist and awarded best female-led project in 2015 in the Global Cleantech Innovation Programme in South Africa (GCIP-SA).
If you are in to nitty-gritty details, the ZingBug makes use of a 48volt electric motor, but due to the draw on battery reserves in stop-start conditions, a hydraulic motor to assist the electric motor. Even with that setup, the Beetle has a range of between 30-75 kilometres, so it will have to make sporadic stops to recharge along the way. That’s allowed under the rules of the “Sustainability Fleet” class in which the team has entered.
So while the ZingBug isn’t bedecked in solar panels like true solar vehicles, the mobile charging station which will fuel it are completely off-grid.
The hydraulic motor, which is used to get the vehicle moving before the electric engine kicks in, is powered through something that ZingCo calls the “Miser System”. This uses the motion of the car to recharge a reservoir.
“The hydraulic motor stores energy, from both engine optimisation and regenerative braking, as compressed gas in an accumulator. The computerised Miser management system then decides which power source to use,” the team explains.
To further drive the point of sustainable green energy, the team will also be using solar power to cook all their food during the eight-day race.