UK water companies may struggle to supply H2 projects

Developers of renewable hydrogen projects in the UK must engage with utilities to ensure there is sufficient water supply to meet the additional demand from electrolysers, delegates heard at the UK Hydrogen-Africa Green H2 Investment Forum this week.

Some water companies in the UK have told hydrogen project developers they do not have enough spare capacity in their long-term plans, Ricardo's director of water and environment Rupert Kruger said. He said developers need to think about water early in the planning process to mitigate challenges. It requires 60-95 litres of fresh water to make a kilogram of hydrogen for electrolysis, cooling, and other functions, and 2–2.5 times as much is needed if desalinated seawater is used.

Insufficient surface or ground water does not necessarily mean hydrogen projects will fail, as developers could tap alternatives such as wastewater treatment plants, industrial water from mines, or desalinated seawater.

But concerns about supply for electrolysers feed into broader problems of potential water tightness in certain parts of the UK. Hydrogen plants will probably face growing competition from industry, agriculture, and domestic consumption, with supply threatened by a warming climate and decreasing groundwater resources. Building new reservoirs is expensive and can be slowed down by local opposition.

Industry body Water UK said demand for water is increasing at the same time as climate change reduces the amount available.

"Companies have developed plans for £14bn of investment in seven new reservoirs, the first of which is already starting construction, as well as cross-country water transfers," it said. The association said it could not comment on water supply for hydrogen plants, but said those proposing new energy projects should engage with the resources planning process through their regional water resources group.

Publicly-available plans show some of England's regional planning groups have started including demand from hydrogen plants in their forecasts, but companies are generally still in the early stages of planning and complain of uncertainty about volume and timing of new demand. The UK has said it wants 1GW of electrolytic hydrogen production capacity in construction or operation by 2025, and at least 5GW capacity by 2030.

A recent report from public body the Environment Agency said water companies are probably underestimating additional needs from the energy sector, including hydrogen projects.

Drier, more densely populated areas of the country, such as the southeast, would probably be more affected than wetter and sparsely populated areas like northern Scotland, according to Kruger. Water has not been an issue for small-scale projects in the north and southwest, one developer told Argus.

But every region in England is heading for a deficit of water supply in the 2030s (see table), unless water companies take additional action, the Environment Agency said. The need to plan water management for hydrogen projects is not confined to the UK.

"This is real life stuff happening in the UK so you can imagine what it's like in other parts of the world," Kruger said. He highlighted disparities in water stress in Africa, noting that while electrolytic projects in broadly-desert Namibia would probably depend on desalination, water stress will not be an issue in its more tropical neighbour Angola, which only makes use of 5pc of its 47 major water catchment areas.

By Aidan Lea