If technology advances – in transport, manufacturing and everyday electrical appliances – represent one of modern society’s greatest triumphs, then one of its greatest challenges lies in delivering those same conveniences and capabilities without increasing global temperatures. Cars, planes and trains have transformed the way we travel, just as automation has revolutionised factory environments. Moving backwards is not an option. In the modern, mobile and digitised world – in which high-energy technologies are often the bellwethers for a country’s economic strength – we must seek alternative routes to energy.
In May, the Committee on Climate Change (CCC) published its Net Zero report, exploring “The UK’s contribution to stopping global warming”. The move to Net Zero provides a great opportunity for UK plc, with its tremendous heritage of world-leading innovation – particularly to find solutions for the hard to decarbonise areas such as heavy goods vehicles, locomotives and space heating.
What has been made very clear by both the Intergovernmental Panel on Climate Change (IPCC) and CCC is that our current plans for climate change mitigation are not enough. A Net Zero target requires systemic changes to the entire energy landscape. It is also clear that there won’t be one single solution; we need a toolkit of technologies to address the wide range of energy uses that are supported by government policy and changes to how we live our lives. These technologies exist; however there is no market or policy drivers in place for their widespread deployment.
Despite its simplicity – a hydrogen atom comprises just one proton and one electron – hydrogen only exists in trace amounts on Earth. It can be produced in different ways, but today most hydrogen is manufactured by steam methane reforming, where, at high temperatures using processes and catalysts developed by Johnson Matthey and others, natural gas is converted to hydrogen and CO2. In the future hydrogen will probably also be produced at similar scale by splitting water into its components of oxygen and hydrogen through electrolysis. In both cases the process can be decarbonised by using renewable energy for electrolysis or capturing the CO2 from advanced reforming technologies and storing it in a process called carbon capture and storage (CCS). That hydrogen can then be used to produce heat and power or used in vehicles with a drastically reduced emissions footprint.
While there has been focus on fuel cell vehicles recently, it is the sectors more difficult to decarbonise that could benefit the most from hydrogen. How do we decarbonise domestic heating, provide flexible dispatchable power generation and decarbonise high-temperature processes in industry?
As the availability of low-cost, low-carbon hydrogen grows it will find more application in other sectors with a lowering of associated cost from production at scale. A key recommendation from the CCC report and others over the last year is that we cluster low-carbon hydrogen production in areas of high-CO2 emissions so that we can cost-effectively implement CCS, also essential for a low-carbon society.
A country’s mobility capability, in general, is a critical economic factor. As well as determining individual convenience, it represents how goods and services are moved around. A school or hospital cannot serve communities effectively without good mobility to match. Hydrogen can help to provide safe, clean, reliable and noiseless travel that is comfortable and efficient for its users. And according to a report from the Environmental Audit Committee, air pollution costs the NHS over £50bn each year. Delivering cleaner energy is a public health concern as well as a central factor in achieving resource efficiency.
The interest in hydrogen as an alternative fuel is largely driven by the potential to manufacture hydrogen at scale with low-carbon emissions. Cars powered by hydrogen fuel cells have additional advantages over other alternative, zero-emission (at point of use) vehicles, such as those powered by batteries. They can be refuelled in a few minutes (faster than electric vehicles can be currently recharged) and have ranges typical of current gasoline and diesel-powered cars.
Where other fuel processes produce energy through combustion, fuel cells produce it electrochemically. Fuel cells, like traditional batteries, consist of an anode, a cathode and an electrolyte membrane. A typical fuel cell moves hydrogen to the anode, where it is split into its constituent proton and electron. The proton then travels through a membrane electrolyte to the cathode, where it reacts with oxygen (from the air), generating water, while the electrons complete a circuit and, in the case of a fuel cell vehicle, drive the electric motors. As there is no combustion aspect to fuel cell power generation and there are no moving parts, they operate almost silently as well as very efficiently.
Fuel cells are, effectively, batteries that won’t run flat or have their capacity reduced with each charge. Provided there is fuel (hydrogen) in the tank (stored on board the vehicle), the process can continue. As fuel cells can be stacked into a “series”, the more fuel cells you combine, the more power you can generate at any one time.
While hydrogen and fuel cells’ case is strong in the long term, the main challenge in upscale is in delivering the infrastructure to support this technology. A hydrogen economy can only be realised with the right level of government support through proactive policy and investment. If we are to expect more people to start using hydrogen fuel cell cars, then more hydrogen refuelling stations must be built and positioned strategically.
Collaboration between government, industry and academia is vital to making hydrogen generation as efficient as possible in the first place, and in installing the infrastructure to enable hydrogen use at scale. The UK has a great record of innovation, and the move towards a hydrogen economy offers great opportunities for UK plc to implement existing technologies based on hydrogen, and to develop new, more efficient ones, which other countries will need as they also look to decarbonise their economies.
Relative to some of the world’s larger economies, the UK’s impact on the global climate through its energy use is small. But supporting the hydrogen economy and leading by example can set a standard for other countries to follow. If the UK gets its own hydrogen economy right, there’s every chance that others will too. With the right commitment to learning by doing, collaboration and investment, it could emerge as a world leader in this vital source of alternative energy.
Sam French and Andy Walker are the new market manager and technical marketing director at Johnson Matthey.