Question: Will cars that run on water still look and work the same as they do today? And wouldn't using water cause a water shortage?

Jemma Rowlandson answered on 18 Jun 2014:

Hi!

The cars are available now, you can actually buy one for $100,000! They look very similar to normal cars but they work in a different way.

To start with you split water into hydrogen and oxygen gas. It’s the hydrogen gas which you put into the car itself. As hydrogen is a gas we have to use a compressed gas cylinder to store it in the car.

The hydrogen gas is then used to power either an engine similar to a normal car producing energy and water, or a fuel cell.

Fuel cells are a bit like a battery, they react hydrogen and oxygen from the air to produce electricity and water (again!). The water that comes out of a fuel cell is actually so pure you could drink it!

Using water certainly could cause a shortage. You would have to be careful not to use water to make hydrogen in areas of the world which do not have enough water. Even England at times has droughts.

Ideally you would use sea water but first you have to remove the salt, then purify it and then split it which makes it much more expensive!