Water-Powered Desktop Calculator

This neat calculator uses a water-based battery to generate enough current so that you can do your sums with the environment in mind! Just top this eco gadget up with some water and it will run for up to 3 months until the water has evaporated. Then you just need to top it up again.

Strictly speaking, the water is not the power source, it’s an electrolytic conductor that contains an ample supply of electrons to flow between the anode and cathode of the special “water battery”. This flow of electronics is essentially a current, enough to power the calculator. This is similar in principle to powering a clock from a potato or lemon.