Which generates more electricity? Treadmills or solar panels? © Getty Images

The thought experiment: Which generates more electricity, running on a treadmill or wearing solar panels?

Slog it out on the treadmill or soak it up on the beach, it's your choice.

1. RUN FOR AN HOUR

© Chris Philpot/BBC Focus
© Chris Philpot/BBC Focus

If you are reasonably fit, you can generate around 700W of electricity on a treadmill. If you run on the treadmill for an hour a day, this would add up to 255kWh per year – or about five per cent of a typical UK household’s consumption.

Advertisement

2. WEAR BODY PANELS

© Chris Philpot/BBC Focus
© Chris Philpot/BBC Focus

The human body’s surface area is around 1.8m squared, but wearing more than 1m squared of solar panels on your clothes would make it too hard to move. Only half of this area would be facing the Sun at a time, giving an effective generating area of 0.5m squared.

3. TAKE A POWER NAP

© Chris Philpot/BBC Focus
© Chris Philpot/BBC Focus

Solar panels typically generate 150W per square metre in good sunshine. If you are outside from dawn until dusk every single day in the UK, this would generate 53kWh per year. If all you do is sunbathe for an hour at midday, it will be more like 10kWh.


Advertisement

Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.