Solar power is normally associated with dull static implementations like hot-water geysers. What if you built a car to run exclusively on power harnessed from the sun, or even better, build a couple of cars and race them across South Africa? Much more interesting!
Sasol has officially announced its support as the title sponsor of this year’s Solar Challenge event. Cavan Hill, Sasol’s general manager – new energy, said that the firm is proud to be part of this environmentally friendly challenge as Sasol is already investing heavily in other renewable or eco-friendly projects.
This is the third time that this FIA-approved, bi-annual challenge will be held in South Africa but this time Sasol is hoping to raise the awareness and profile of the event. This is an ideal opportunity for schools, universities and industry to get involved with advancements in solar energy technology while stimulating the engineering minds of the future.
The Classes
Sasol has tried to widen the entry criteria to maximise the number of entries. Some of the classes are stipulated by governing bodies like the FIA but others encourage students and industry to participate without the need for access to huge budgets. Four classes will be eligible to enter the race namely:
Olympia Class
• Conforms to the constraints of the FIA Regulations, this is the primary class in the Sasol Solar Challenge in South Africa, it represents the move to more road capable vehicles;
• Four wheelers only;
• 6 m2 maximum solar array;
• Lights required;
• Reverse gear required.
Challenge Class
• Primary Class in the World Solar Challenge in Australia;
• 6 m2 maximum solar array;
• Three wheels allowed;
• Less strict on braking and electric wiring requirements than the Olympia class.
Adventure Class
• For teams not interested in competitive racing but rather the experience;
• 8 m2 maximum solar array allowed to enable heavier, less aerodynamic cars to finish event.
Technology Class (Green Fleet)
• Any technology vehicle, including production cars, solar, hybrids, electric, fuel cells, any low emission vehicles, etc.;
• Technology demonstration only, no racing;
• This is an Eco Class to show the most efficient technology that is currently available on the roads.
For more info visit: www.solarchallenge.org.za.
The Route
The cars will complete a total of 5 000 km around the country. Each day will be treated as a separate stage. The route will start and finish in Pretoria and include major cities such as Cape Town, Bloemfontein and Durban.
Engineering
Each solar car combines most of the engineering disciplines and consists of the following:
• Chassis including steering, braking and suspension;
• Body including the solar array;
• Powertrain including electric drive, batteries, controllers etc.
The idea is to build the most efficient vehicle possible. As each vehicle has access to the same power source, the sun, the most efficient vehicle will be able to cover the distance at the highest average speed. Battery capacity is capped at approximately 5 kW.hr.
Strategy
Each solar racecar will have a lead and chase vehicle with radio contact for safety reasons. The chase car is also used as a basis by engineers to monitor the telemetry (battery conditions, charging rates, vehicle speed etc.) coming from the vehicle in real time. The typography of the route plays a major role as down hills can be used to charge the batteries (regenerative braking) and increase the average speeds on level roads. Obviously, enough energy needs to be available in the battery before tackling an uphill section to prevent the car grinding to a halt. Think Formula One team next to the pit straight and you have an idea.
The Race
The cars may start the race with a full battery for the first stage. After this no external energy source except the sun will be allowed to provide energy. After each stage the vehicles will be prevented from receiving further energy from the sun or other sources. The solar car finishing the stage first will be declared the winner.
Summary
South Africa needs technology show cases like the Sasol Solar Challenge to encourage students to become interested in engineering. The industry is also likely to benefit from any new developments in solar technology and efficiency sprouting from this challenge. Let’s hope the sun shines on all the participating teams!
