The big question: how impactful could hydrogen be in decarbonising the economy?
Policy manager, New Energy Services and Heat (NESH), Energy UK
“Several projects are starting to address the challenges involved”
Hydrogen could help decarbonise the UK’s heat, power, transport and industrial processes, as well as provide large-scale, long-term energy storage. The biggest potential market is low-carbon heat.
The UK is unlikely to be a major producer of hydrogen via electrolysis, given its lack of excess renewable generation. It will rely upon steam methane reformation and auto thermal reforming. Two challenges exist – efficiencies in production processes, and the application and integration of carbon capture, utilisation and storage.
Several projects, including H21 Leeds City Gate, HyNet in the North West and ALIGN-CCUS in Teesside, are starting to address these challenges, complemented by broader work focused on end use – primarily Hydeploy at Keele University and the government-backed Hy4heat. These will help establish hydrogen supply chains, including compatible appliances for end users, and will determine the requirements for repurposing current gas distribution networks and storage facilities.
For hydrogen’s impact to be quantified, the projects should be bolstered by incorporating a range of other low-carbon technologies and business models into large-scale trials, establishing the UK as a global leader.
Manager, Alternative Fuels, Toyota
“Hydrogen can now offer economically viable solutions”
Apart from its emissions advantages, the hydrogen case is so compelling because of its versatility. It allows energy to be produced locally from many sources, including waste and surplus intermittent renewables. It can be stored indefinitely and shipped relatively easily. It can be used for industrial feedstock, and can produce emission-free heat and power for a range of applications, including transport, homes and businesses. Driven by greater awareness, changes in attitude and scientific developments, hydrogen can now offer economically viable and socially beneficial solutions.
In the long term, Toyota sees hydrogen fuel cells replacing the petrol engine in a hybrid system. In 2015, we introduced the world’s first mass-produced dedicated fuel cell vehicle, the Mirai, and we have increased production in line with the development of the hydrogen infrastructure and customer acceptance.
There is potential in battery electric vehicles, but charging time, range and battery costs limit their benefits. Mass adoption will not happen unless energy storage and better grid distribution are addressed. Hydrogen production and storage could solve these issues. The transition will be challenging – but the adoption of renewable, clean and low-cost energy is imperative.
Professor Robert Steinberger-Wilckens
School of Chemical Engineering, University of Birmingham
“An alternative to pure hydrogen is the synthesis of methane”
Hydrogen can be produced relatively simply, using renewable electricity to split water. It can then be converted back into electricity or heat by fuel cells, resulting in the sole emission of water.
In this way, renewable electricity not only helps decarbonise the electricity supply, but can also be used for heating and as a fuel in electric vehicles with a fuel cell drivetrain. This is only worth doing, however, if the energy input comes from a renewable source – otherwise emissions are simply shifted from point of use to point of production.
Mixing hydrogen into the natural gas supply system is one way carbon footprints could be reduced. However, burning hydrogen in boilers or gas engines will produce nitrous oxides and other urban air pollutants.
An alternative to pure hydrogen is the synthesis of methane from hydrogen and carbon dioxide. This is net carbon-free if the carbon dioxide originates from plant matter and is fully compatible with gas infrastructure. Methane can also be converted back to electricity and heat in certain fuel cells at high efficiencies. This could be an easier way to decarbonise heating energy supply, since it makes use of the current supply system while increasing energy conversion efficiency.