• Paul

Hydrogen - A renewable resource

It has been talked about for over 5 years, but now it is becoming a reality. This week, the go-ahead was given for the first 100% hydrogen gas network to be introduced in Fife, Scotland. This move is a giant step towards using hydrogen as a renewable resource in place of our current carbon-heavy Natural gas.

What is Natural gas? Natural gas, used in the UK is Methane, chemical formula CH4.

This equates to four hydrogen atoms attached to one carbon atom creating the methane molecule. It's the carbon part of methane that is damaging to our planet, and it is carbon that is the driver for Government's ambitious carbon reduction targets.

If we were able to move everyone away from carbon-intensive methane onto a cleaner fuel, then we would be well on our way to achieving our goals, given that the heating of our homes and our hot water accounts for over 60% of fuel demand in the UK. And that's where these ambitious Hydrogen projects come in.....

Why Hydrogen for heating?

  • Hydrogen can be carried through the current gas infrastructure - pipes have been significantly upgraded to mainly PP over the last 25 years

  • Hydrogen is the most abundant element in the universe!

  • Hydrogen has zero carbon content, meaning the UK could potentially be the world's first country to be carbon zero at the point of use

  • Although the calorific value of hydrogen is lower than that of methane, meaning less energy, the molecule is much smaller allowing much more to be burned, meaning that the Wobbe index (the index used to compare the way gases burn) is very similar

  • Hydrogen can be used for much more than methane. For instance, many car manufacturers are looking towards hydrogen fuel cells to power their vehicles, meaning that the same network we use for heating our homes, could also run your car!

But surely hydrogen is highly flammable and explosive?!

So is methane! And we seem to have mastered that! Older readers may remember back to when the UK had "Towns Gas" This was a gas that ran the UK up until North Sea Gas was discovered. In the late sixties and early seventies, the whole network was moved from Towns gas to today's natural gas. The irony? Towns gas was a mixture of methane and hydrogen, so already had a lower carbon intensity....

But if we moved the whole country from one gas to another once then we can do it again.

So what has happened this week?

This week, the first of many projects looking into the viabiity of 100% hydrogen appliances was given the go-ahead to deploy in 2022 in Fife, Scotland. The town of Levenmouth will see a pilot program offered to it's residents offering a free hydrogen connection, free replacement appliances and free servicing and maintenance of those appliances for the duration of the trial. In addition, the price per kWh has been capped at the same rate as they would have paid for natural gas.

Hydrogen fuel for Levenmouth
The town of Levenmouth, the first to have 100% hydrogen fuel

This makes the offer quite an appealing one. Phase one will see 300 homes hooked up to hydrogen, with phase two looking to increase that number to 1,000 households.

Where will the Hydrogen come from?

Arguably, this is the best part. The hydrogen gas will be formed by electrolysis of water. By passing an electric current through plain old water (The current will be supplied by off-shore wind generation by the way), the water molecule will be split out into Hydrogen and oxygen. The hydrogen will be stored, and used to power the new network.

And the beauty of burning hydrogen is the only by-product is water. For those readers with a modern condensing boiler, you should be familiar with a condensate pipe carrying the condensate water outside or to a drain. This is slightly acidic. However, with a hydrogen boiler, the condensate is pure water. All four of the big UK boiler manufacturers already have prototype boilers running on pure hydrogen and hobs and fires already exist for other markets.

Hydrogen boiler
Hydrogen boilers on a test bench

When could we see mass deployment of a hydrogen network?

This trial will certainly set the ball rolling. There are other projects all over the UK that are doing similar things. We already know that no new build homes will be allowed to have a fossil fuel boiler fitted from 2025 onwards in the UK, in the same way the Netherlands have been for three years. In the short term, it was envisaged that heat pumps would be used to a much greater extent in those new build homes, but it could just be that another contender has just ridden into town.

You can read more about the exciting project at https://www.sgn.co.uk/H100Fife Using hydrogen as a renewable resource

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