Comment by rcxdude

There's two different classes in the WSC - one is basically 'make a race car' with very little view to practicality, most of the rules are about limiting the competitive speed to be below the speed limit and having some semblance of safety. Entries to this one are almost always 3 wheeled because it's optimal from an efficiency point of view (aerodynamics and rolling resistance). (Two-wheeled designs are not allowed). The other class (which the car you linked entered under) is meant to be a bit closer to a practical vehicle, and one of the rules is that it needs to have four wheels. It also is allowed a larger battery, which can be charged at certain points during the race (the other class starts with a fully charged battery but it's nowhere near enough for the race, and only solar power is allowed from that point on).