What is the 'hydrogen economy' and is it really the answer to lowering carbon emissions?

Hydrogen could supply a third of the UK's energy by 2050, as ITV Science Editor Tom Clarke reports

Today, the government launches its plan to make the UK the world’s leading “hydrogen economy”. 

Why? Because hydrogen is one of the few sources of energy you can use without producing carbon dioxide or other greenhouse gases. When you burn it, it produces nothing but heat and pure water. 

Most energy experts welcome the idea - hydrogen is seen as the only practical way many sectors of the economy can meet net zero climate change targets. Particularly ones that are currently reliant on natural gas or liquid fossil fuels (like heavy industry, chemical refining, and transportation).

The strategy announced today by Energy Secretary Kwasi Kwarteng will invest more than £100 million in industries that produce and transport hydrogen. They want to apply a similar model for subsidising hydrogen as they used to expand offshore wind in the UK.

The government claims “a booming, UK-wide hydrogen economy could be worth £900 million and create over 9,000 high-quality jobs by 2030”.

"Booming" might not have been the word I’d have chosen. There’s a reason hydrogen never took off as a fuel in the past: it has a tendency to explode. 

It’s one of the main reasons why no one has (yet) tried replacing natural gas with hydrogen as a source of fuel in our homes.

On Tuesday, we filmed a trial by Cadent and Northern Gas Networks in Gateshead that is mixing 20% hydrogen into the gas supply. But going full hydrogen is a way off yet. 

Aside from safety, hydrogen is likely to corrode the existing gas pipe network, and the tiny molecules leak out of cracks more easily than chunkier natural gas molecules.

It’s why most energy experts predict hydrogen won’t end up being used as a fuel for heating homes or cooking food. The real market for it will be in replacing gas in industrial furnaces, or fossil fuels current used as the raw material in the fertiliser industry, and for powering fuel cells in hydrogen trains, lorries and buses.

The challenges for a low carbon hydrogen economy don’t end there. Currently the cheapest way to produce hydrogen is to extract it from natural gas. Fossil fuel companies like BP and Cadent are making bold claims for how they can then capture and store that carbon under the North Sea. Hydrogen derived from fossil fuels in this way is called “blue hydrogen” in the jargon.

But many experts warn blue hydrogen still has a high carbon footprint, and the technology for storing the left-over carbon dioxide is unproven at scale. 

“The government should be alive to the risk of gas industry lobbying causing it to commit too heavily to blue hydrogen and so keeping the country locked into fossil fuel based technology, making reaching net zero more difficult and costly,” says Jess Ralston, an analyst at the Energy and Climate Intelligence Unit.

It’s noteworthy that the co-chair of the government’s Hydrogen Advisory Council is the UK boss of oil major Shell.

“Focusing on green hydrogen could unlock the our full industrial potential, bringing with it lifelong jobs in places like the North East, supporting both the government’s climate goals and its levelling up ambitions.”

True zero carbon, or “green” hydrogen, is made by using electricity to split water into hydrogen. But this is currently much more expensive and could require unrealistic amounts of offshore wind power if we tried to replace all our current demand for natural gas with green hydrogen.

Summing this all up, a hydrogen economy is nothing short of essential to a sustainable future. Expecting to use hydrogen as a like-for-like replacement for fossil fuels, however, would be cripplingly expensive.

Like most of the planned transition to net zero it’s partly about changing the tools and technologies our economy relies on, but also about changing our economy to keep working in a rapidly warming world.