The Solar-Powered Car

In a feat of enterprise and endurance, Hans Tholstrup drove a solar-powered car across Australia in 1979. The car had a large flat roof arrayed with photoelectric cells that turned the sun’s radiation into electricity and charged a battery.

Solar radiation cannot deliver more than about a kilowatt, roughly an old-fashioned horsepower, per square metre at ground level, and it usually delivers less. Allowing for the conversion rate of photoelectric cells, and the fact that the cells couldn’t block in the whole roof area, then ten square metres, an unwieldy burden, couldn’t deliver more than about a horsepower to the motor.

But the average petrol-driven car, whose normal function is to carry just one person, delivers about one hundred horsepower upwards. This is regarded as a “basic necessity”. If this be true, the the directly solar-powered car is not feasible.

But if one horsepower maximum is all you need to carry two people, as were carried in the 1979 trip, across a continent, then our transport needs could be met using such small amounts of liquid fuel as to make it forever unnecessary to lumber a huge collector about in the first place.

The Tholstrup car was nothing more than an entertaining irrelevance to the whole problem of evolving rational, sustainable energy policies for the future.