How does a hydrogen fuel cell work?
Hydrogen fuel cell vehicles work by using it in a fuel cell, where it is combined with oxygen and the resulting chemical reaction generates electricity. It is a clean process with the only by-products – apart from electricity – being warm air and water vapor.
In many ways a hydrogen fuel cell works much like a battery except that rather than needing to be recharged regularly from an external source, a fuel cells generates electricity directly, and will do so as long as hydrogen, one of the most abundant resources on earth, is available. Hydrogen powered vehicles also have many of the same advantages of electromobility – no tailpipe emissions and low noise.
If the hydrogen is produced from a renewable source, it can emit very low well-to-wheel emissions. However, as it stands today, around 95% of the hydrogen produced comes from fossil fuels, such as natural gas and oil. This has a significant impact on hydrogen’s overall climate impact and naturally more hydrogen would have to be produced from renewable resources for the technology to have better green credentials.
What are the challenges and opportunities?
A significant barrier to the wider adoption of hydrogen vehicles is the cost of production of fuel cells, which means that as a fuel source hydrogen is roughly 3-4 times more expensive than diesel. There are also large gaps in infrastructure which is costly to build and today there are not enough hydrogen vehicles on roads to make this profitable.
However, these challenges are not insurmountable and hydrogen fuel cells still offer huge potential as a clean source of fuel. For this reason, China, Japan, and South Korea are betting big on hydrogen with China setting the goal of having 1 million hydrogen vehicles by 2030 which is a significant increase from the current 1,500. Japan meanwhile has set its targets to 800,000 vehicles on roads around the same time. This makes a lot of sense for resource-poor countries like Japan where hydrogen can provide all the benefits of electromobility without adding further pressure on the country’s’ power grid.
Many proponents of hydrogen technology believe that it is a more viable alternative to diesel trucks thanks to longer range and shorter refuelling times. Recent experiments with new material like manganese hydride show that it is possible to extend range even further by designing tanks that are smaller, cheaper and more energy dense than existing hydrogen fuel cell technologies.
Is hydrogen the fuel for the future?
So what is the verdict on hydrogen? Well, as long as hydrogen fuel cells offer the potential to switch to greener transport, I believe that it should be a technology that we continue to research and develop.
As with any discussion around alternative fuels, hydrogen vs. electric trucks should not be framed as ‘winner takes all’ argument. Rather we should consider the advantages and disadvantages of each alternative and understand that each solution will be competitive for different operations, regional needs and at different points in time.
Despite the clear cost and infrastructure advantages of battery powered vehicles over hydrogen cell technology today, the truth is there is no silver bullet. Both technologies face different challenges that cover infrastructure, customer acceptance, grid impact, maturity and driving range.
