6 August 2013 – A team of students from Wits University in Johannesburg is racing to find sponsorship and finish building its sun dog in time for the Sasol Solar Challenge.
Every two years, teams of students from tertiary institutions in South Africa and overseas design and build solar powered vehicles to compete in the Sasol Solar Challenge which covers 5,400 km of variable South African terrain. The race is the longest of its kind anywhere in the world.
In 2012 a Wits team competed in the challenge for the first time and finished fourth. The 2014 event will be the fourth ever Sasol Solar Challenge and Wits is planning to compete using a new vehicle – the Parhelion – which is being built largely by the school of mechanical, industrial and aeronautical engineering.
The name Parhelion was inspired by a phenomenon of the sun which results in the formation of a halo or circular rainbow around the sun. The common term for this phenomenon is sun dog.
The solar car will travel at 100 km/h using the same amount of electricity as an average hairdryer. It will be able to reach speeds of around 120 km/h. The entire car will weigh around 170 kg, about the weight of two grown men. Materials used in construction include carbon fibre composites, the same as those used in Formula 1. The amount of drag generated by the entire car will be almost the same as putting your hand out of the window on the highway. The batteries used in Parhelion are the same kind as those used in a cell phone. The solar car will be 2.0 m wide and 4.5 m long – almost twice the length of a smart car. The car must be able to drive 5,400 km in eight consecutive days. Only 23% of the sunlight captured is converted into electricity.
According to team leader Bradley Rautenbach the Wits team wants to push the boundaries of technology and showcase the feasibility of renewable energy in the transport and energy sectors. The Parhelion is designed to optimise energy from sunlight using a semi-monocoque carbon fibre chassis, along with latest generation lithium-ion batteries, which will ensure that the car is extremely lightweight.
The next race will take place in September 2014. According to the new rules proposed by the organisers, the cars have to compete in a track event about three months before the main event.