NOT ALL HOT AIR: How Hydrogen will heat our homes

We’re facing a climate emergency that means we’re going to have to find more energy efficient ways to heat our homes.

At the moment, a quarter of all the energy that is used in the UK goes to keeping our homes warm and heating our water.

About 85% of homes use natural gas to do this.

But burning natural gas creates pollution, including carbon dioxide, which causes global warming, so there is a big effort to find cleaner, greener ways to heat homes.

One of the solutions that’s in the pipeline – literally - is to switch from natural gas to hydrogen.

And heating homes with hydrogen is nothing new.

Back to the future

It’s not that widely known, but British households were already using hydrogen mixtures for heating until the 1970's, when large resources of natural gas were found under the North Sea and gas distribution pipelines were built across the UK.

Before that, we used ‘town gas’, which was up to 60% hydrogen.

Now, hydrogen is coming back, but what is it and why is it better than natural gas?

Hydrogen is a non-toxic flammable gas that can be burned to generate heat.

Crucially, when you burn hydrogen, the only byproduct is water, so no Carbon emissions are produced.

But hydrogen is harder to make use of than natural gas, largely because it can’t just be extracted from the ground, like natural gas.

Instead, it has to be manufactured.

Colour coded

There are different ways of making hydrogen and some are more environmentally friendly than others.

While the end product is always the same, it is given different names to identify the method of production used.

So, we have black hydrogen, which is made from coal in a process that also produces carbon dioxide. This is the least environmentally friendly way of making hydrogen.

Then there’s blue hydrogen, which uses natural gas, but the CO2 which is produced is captured and stored underground, so it doesn’t damage the atmosphere.

The most environmentally friendly form of hydrogen is green hydrogen, which doesn’t use fossil fuels at all, or produce any CO2.

It uses renewable electricity, often from wind turbines, to create hydrogen out of water in an electrolyser (a carbon-neutral process).

The idea of heating homes with hydrogen isn’t some far-fetched idea for the future.

In fact, trials of hydrogen mixtures are already happening in the UK, with 100% hydrogen trials planned for the end of the decade.

In our next blog, we’ll explore the technology being developed to harness the power of hydrogen to heat UK homes and look at a timeline for the transition to hydrogen.