As challenges around the energy transition continue to present themselves, it’s thought that hydrogen technology could offer some answers. As carbon reduction goals threaten to move beyond reach, the energy industry needs realistic, interim solutions that can be used on the path to decarbonisation – and it seems that hydrogen energy systems may just be the missing link.
It’s important to recognise that large-scale investment in solar parks and offshore wind farms is a huge step forward, but as these investments increase, so does our dependence on varied renewable sources. Essentially, more variable generation requires a more flexible power system – for example, what happens when there’s too little (or too much!) wind or sunshine? As an energy carrier that can be stored in large quantities, hydrogen – and green hydrogen technology in particular – may be the answer.
Hydrogen which has been produced through renewable power can serve as a conduit for storing large amounts of energy produced during sunny or windy days, and stored power can later be used in sectors such as heavy industry and transport that are difficult to electrify directly.
Today, the bulk of hydrogen production comes from steam methane reforming and coal gasification – and of the little amount produced via electrolysis, very little runs on renewable energy. It’s thought that proton exchange membrane (PEM) electrolyser technology may eventually deliver greater flexibility and compatibility with different electricity markets, as well as a wider operating range.
The main drawback of PEM technology has been the relatively high cost of use, however, these costs are rapidly falling and it’s predicted that by 2025 the overall capex of PEM systems will have fallen to just €700/kW.
Ideally, we will see a faster transition from so-called ‘grey’ hydrogen routes, which rely on fossil fuels. Worldwide, natural gas, oil, and coal are the core hydrogen energy sources, with just 4% delivered via electrolysis. But, due to the increasing availability and cost-effectiveness of renewable power sources, the coming years should bring a tipping point where green hydrogen routes can start to become competitive.
Accounting for around 22% of global carbon emissions, the transport sector is key in the transition to a low-carbon society. Green hydrogen can offer long-term answers: namely extended driving ranges and rapid refuelling versus the time it takes to charge today’s electric vehicles (EVs). In Asian markets, such as Japan and China, the demand for hydrogen vehicles is steadily growing, and there are organisations working with smaller companies to help scale up the potential application of this technology.
In the majority countries, hydrogen-cell-based mobility is some years away from being a mainstream solution, and so existing, non-green hydrogen routes may offer an immediate path ahead.
Here in the UK, alternative energy innovator, AFC Energy, is developing the world’s first electric vehicle charger based on hydrogen, which will enable electric vehicles to be recharged with power generated by a hydrogen fuel cell. As we wait for pure hydrogen-powered vehicles to become market-ready, blue hydrogen could help accelerate the mobility sector’s transition to carbon-free alternatives.