If we could power such an elevator with solar energy, we could simply rise up into space for a fraction of the cost of a trip by rocket or shuttle.

His food would be cooked on a rocket stove made from two old catering tins, and he would wash in a solar shower essentially a black plastic bag suspended from a tree, and warmed by the sun.

The idea that solar energy will have to wait for a breakthrough to reach grid parity is "crap," he says. He adds: "We're not talking about rocket science. We're talking basic engineering.