Producing hydrogen and blending it safely with normal gas requires the right technology.
The research, development and production of the technology for HyDeploy is being supplied by project partners ITM Power and the Health & Safety Laboratory. It is supported with gas network operating knowledge from Cadent and Northern Gas Networks.
The hydrogen for HyDeploy will be produced using electrolysis. Electrolysis uses electricity to split water into hydrogen and oxygen.
An electrolyser is the most practical way to produce hydrogen for a project of this size and duration. It avoids the need to transport and store hydrogen on site, or build extensive infrastructure. For HyDeploy, an electrolyser will be installed on the Keele University site.
Beyond HyDeploy, efficient large scale hydrogen production is a developing area. Ideally, hydrogen production uses renewable energy sources, such as wind and solar power. In the UK and Europe, electrolysis powered by renewable sources produces the majority of low carbon hydrogen for commercial use.
Steam Methane Reforming (SMR) is another way to produce hydrogen at scale. SMR is a process where methane from natural gas is heated with steam, usually with a catalyst to produce a mixture of carbon monoxide and hydrogen. This is used today to produce large volumes of hydrogen in the UK and world-wide. To deliver low carbon hydrogen, the use of SMR would require deployment of Carbon Capture and Storage (CCS). There are projects in the UK and internationally looking to develop CCS technology.
Biohydrogen can also be produced from certain kinds of biomass, e.g. waste (see BioH2 project – Cadent, Advanced Plasma Power and Progressive Energy).
The current regulations for gas in the UK restrict hydrogen levels to 0.1%. This level was set based on the supply of North Sea Gas which has naturally low hydrogen levels. However, hydrogen in the UK isn’t new. It was the main part (40-60%) of old ‘Town’ gas, which was used in the UK before North Sea Gas.
HyDeploy aims to be the first project in the UK to inject hydrogen into the modern gas network. Before a live trial can go ahead, the Health & Safety Executive must grant a special exemption to the existing regulations for the delivery of blended hydrogen and normal gas.
A national programme of gas mains pipe replacement is currently underway, upgrading iron pipes to durable plastic pipes.
Although these new plastic mains gas pipes are suitable for transporting hydrogen, it is important to make sure that all the different materials found on the network work safely with hydrogen. HyDeploy is carrying out extensive research on these materials. This builds on previous UK and international research and will form an important part of the evidence presented to the Health and Safety Executive in seeking approval to undertake the live trial.
Other energy industry projects are looking at how higher concentrations of hydrogen could work on different parts of the national network (Northern Gas Networks, H21).
The mixing of the hydrogen and the normal gas will happen before the gas enters the pipes. This will be done in a special injection and mixing unit which can be carefully controlled and monitored to ensure that the hydrogen and natural gas blend remains consistent as gas flows vary.