Batteries safe enough to eat

The problem with clean power from wind and solar: you need to store it in batteries that are expensive – or made of dangerous things like lead and acid. The solution? A new cheap kind of battery that’s so safe, its inventor says you can eat them.

The batteries being made by start-up company Aquion are bulkier and heavier than the lithium-ion units currently used in cars and phones, so won’t be suitable for places where size is an issue. However financial backers including Bill Gates believe they could be a safe and low-cost way to solve the storage problems faced by renewable energy – especially as they last more than twice as long as lead-acid batteries.

Ultimately, if the batteries take off it could mean being able to flick on a light switch at night that’s powered by solar energy captured earlier that day – or last week – without it costing you the earth. Eating them isn’t recommended however – their inventor says they taste “terrible”.