Energy world

Hydrogen fuel cell

Status: Renewable if the hydrogen fuel is created using electricity from renewable sources

How do they generate electricity?

Water is a compound made from hydrogen and oxygen. If you pass an electric current through water, it can break the bonds in the molecules and split them into separate hydrogen and oxygen molecules. The oxygen and hydrogen are released as gases and can be collected in separate containers. This process is known as electrolysis.

A fuel cell is a device that uses electrolysis in reverse. It converts hydrogen and oxygen into water, producing electricity and heat in the process. This is all done without the need to burn the hydrogen.

Where can you find it?

In theory, it is possible to use the oxygen in the air, and the hydrogen in water.

Advantages and disadvantages of using hydrogen fuel cells to generate electricity

Advantages

The only wastes produced are water and some heat, which can be reclaimed

Operation is entirely silent

Fuel cells can be built in a huge range of sizes to suit almost any use

Disadvantages

Fuel cells rely on hydrogen fuel, which may be produced using non-renewable energy sources

It will be some time before hydrogen is as freely available as petrol is at the moment

Hydrogen is highly flammable

How many plants in the UK?

There are a handful of small-scale plants in the UK that supply single or small groups of buildings.

How much does a hydrogen fuel cell cost to produce?

It is difficult to say.

What is the carbon cost?

If the hydrogen is generated by renewable means, the carbon emissions could be zero.

The future?

It has great potential for small-scale use, but it is unlikely the UK will develop any large-scale plants in the near future.