Could hydrogen power save the planet?

As world leaders wrangle over climate change targets in Glasgow, one technology that could help make them a reality is attracting a lot of buzz. Hydrogen – long used in rocket fuel – is being touted as a revolutionary low-carbon energy source. It already powers some UK buses and French trains, and its advocates say it could also be harnessed on a mass scale in cars, aircraft, as well as in people’s homes.

Construction equipment maker JCB has just signed a multi-billion-pound deal to import and supply hydrogen produced using renewable energy. And Morgan Stanley has predicted that if governments honour their carbon-cutting commitments (a big if) then sales of hydrogen could total $600bn by 2050, up from $150bn today.

What is hydrogen? And will it live up to the hype?

Unlike natural gas, coal and nuclear, hydrogen isn’t a primary energy source, although it can transmit energy (like electricity) and can also store it (like a battery). It doesn’t emit carbon at the point of use, but needs energy to make it in the first place, meaning it’s only as green as its method of manufacture.

The versatile gas has a number of highly specialised uses. “Grey” hydrogen – produced from splitting water into its constituent parts using fossil fuels – plays a crucial role in the production of steel, plastics and ammonia (an essential ingredient for fertilisers).  

The holy grail for hydrogen enthusiasts is to slash carbon emissions in these sectors by producing “green” hydrogen using renewables instead. A big leap forward came earlier this year when Hybrit, a Swedish conglomerate, used green hydrogen technology to produce the world’s first ever carbon-free steel.

The snag is that using renewable electricity to produce it is less efficient than using that electricity as a direct power source, which makes its wider rollout into transport a more complicated proposition. 

However, the gas can also be used as a battery substitute. One of solar and wind’s biggest drawbacks is the unpredictability of supply. But converting renewable power into hydrogen allows it to be stored for much longer and much more efficiently than regular batteries, and turned back into electricity when required. Countries like Australia, with lots of wind and sun but poor transmission links to the rest of the world, are eyeing up hydrogen as a way to export energy.  

Although hydrogen has been around for a while, its green variant shares the big drawback of many nascent technologies: cost.

Green hydrogen costs four times as much as grey hydrogen to produce. Christian Bruch, CEO of Siemens Energy, said last month that there was “no commercial case” for the green hydrogen sector for the time being. “Cheap electricity…and abundant renewable energy” was needed to make the industry viable.  

It’s why pragmatists see green hydrogen as part of a medium-term solution. Even so, experts believe costs could fall dramatically, given the right conditions. “As renewable energy capacity demand increases and prices drop, the cost of hydrogen production by 2030 could drop by 70 per cent from current levels,” says Carolina Dores, Co-head of the Morgan Stanley European Utility team. “The key to cost savings could be hydrogen production facilities built jointly with wind/solar farms, so producers could generate power without incurring grid fees, taxes and levies.”

Indeed, global manufacturing capacity is already expanding. Humberside is fast becoming a hub for zero-carbon infrastructure, including hydrogen, while Saudi Arabia, the world’s largest oil exporter, is planning a $5bn plant to produce clean hydrogen at its futuristic city, NEOM.

The technology is likely to play a supporting role in the green energy revolution; clean hydrogen has the potential to cut global carbon emissions by a modest 10 per cent by 2050. But despite its drawbacks, it could yet prove a crucial part of the puzzle.