Solar flight...

What a fantastic achievement! Having touched down in Abu Dhabi, Solar Impulse 2 has completed the first round-the-world flight by a solar-powered aeroplane. It’s a strange-looking craft, with a wingspan greater than a Boeing 747, and 17,000 solar cells mounted on the wings. A quarter of the plane’s weight is taken up with batteries, which store the solar energy during the daytime, and provide the motive power to turn the propellers at night. The plane could, in theory, stay airbourne almost indefinitely, but the pilot needs to recuperate after each leg of the flight. In the unheated and unpressurised cabin there’s only a single seat, which, I read, doubles up as a toilet.

The plane may be impractical in its present form, but year-on-year the technology will improve. Batteries, in particular, will get smaller and smaller. I’m cheered whenever I see power being generated by wind and wave and sunlight. It means we’re heading in the right direction…

Astley Hall...