Hydrogen is making a comeback. Once the major element in the ‘town gas’ used for cooking, heating and lighting in homes across the UK for 150 years, hydrogen was displaced as a source of power by a vast conversion programme to ‘natural gas’ during the 1960s and 1970s to take advantage of gas fields in the North Sea. However, with 57% of natural gas now being imported and the UK’s production falling, the time may be right to switch back to hydrogen.
Dr Scott Steedman CBE FREng
Pilot tests of hydrogen-fuelled trains are already under way in Germany. Hydrogen cars and buses are on the roads today in the UK, but the popularity of electric vehicles and the shortage of hydrogen refuelling stations has limited their take-up. Now, a series of feasibility projects is investigating the wider potential for the use of hydrogen in buildings and transport as a major source of renewable energy.
In November last year the Department for Business, Energy and Industrial Strategy (BEIS) appointed an Arup-led consortium that includes Kiwa Gastec to manage a £25 million Hydrogen for Heat programme, which is researching the use of hydrogen in domestic appliances and potential technological solutions that would address safety risks and minimise disruption.
Political interest in hydrogen is also rising. On 3 July, a new All Party Parliamentary Group on Hydrogen held its first AGM, chaired by Anna Turley MP and backed by industry as well as leading trade unions, which see the potential for creating employment.
There are plenty of hurdles to overcome, but the main challenge is the infrastructure itself. Converting your cooker to burn hydrogen is just the start. Every appliance in an area needs to be modified or changed before any switch to a new fuel. The gas network needs to be able to distribute enough supply of hydrogen to meet peak demand. Hydrogen can be made from water using electrolysis, but the more common approach is to use methane (via a process called steam methane reform). If methane is the feedstock for hydrogen, the CO2 released needs to be securely stored to achieve a carbon neutral source of energy.
The pioneering H21 Leeds City Gate project, led by Northern Gas Networks, is investigating how a switch to hydrogen can be achieved in practice. Working with the city of Leeds, H21 has confirmed that the existing gas distribution network not only has the capacity but could be converted, stage by stage, with minimal disruption to the public. After all, the UK has already been through the reverse process when it switched off town gas.
In an alternative approach, Keele University is halfway through HyDeploy, a project that will blend hydrogen with natural gas on its 600-acre campus. The aim of HyDeploy is to determine what proportion of the conventional gas supply to homes could be substituted by hydrogen without requiring modification of existing appliances. If HyDeploy succeeds, producers might be able to mix up to 20% hydrogen into the normal gas supply. With the first phase of the HyDeploy project now complete, the Health and Safety Executive (HSE) will assess the results of safety checks in homes and buildings prior to a live trial starting in 2019.
Hydrogen could also make sources of renewable electricity in remote and rural areas more efficient by providing a means of energy storage. Since 2013, Orkney has been a net exporter of electricity but without storage, the turbines have to be shut down when the power is not needed. Surf ‘N’ Turf is an innovative community project on the Orkney island of Eday, where there is a test site for manufacturers of tidal turbines. Together with a 900 kilowatt wind turbine on the island, these offshore turbines create more power than the islanders can use. Instead of losing the excess energy, Surf ‘N’ Turf uses electrolysis to produce hydrogen and oxygen. The oxygen produced by the electrolyser is released to the atmosphere and the compressed hydrogen shipped to Kirkwall, where a fuel cell generates heat for nearby buildings and auxillary power for ferries docked in the port.
With these and other projects underway, the signs are promising that in the near future hydrogen may yet again play an important role in the UK’s energy mix. With vision and commitment, this quiet and imaginative revolution looks increasingly like an emerging industry with national impact and international opportunity.
Dr Scott Steedman CBE FREng