Renewable Hydrogen from Surplus Wind Power

As an engineer, I find it incredibly exciting to be part of the movement turning net zero into a reality. It’s fascinating to see different technologies pushing the boundaries, each striving to play a role in decarbonisation. There’s a lot of debate around electrification versus hydrogen—both are essential, but the real challenge is figuring out how to make the best use of them together.

Wind Power – Successes & Challenges

UK’s adoption of wind power has been recognised as a huge success story. However, transmission and storage haven’t kept pace with the increasing generation capacity. As we move towards largely weather-dependent renewable power generation, the power network will need to be designed with the resilience to manage the variation in power from hour-to-hour, day-to-day and season-to-season. At present, most of this variability is managed with fossil fuels such as natural gas fired power systems.

For our future decarbonised energy grid, a combination of over-generation capacity and energy storage will be required. A small amount of over‐generation (and curtailment) can reduce the requirement for energy storage and lead to a lower overall system cost. Based on present cost assessments, future renewable electricity generation systems that have around 15% over-capacity appear to be optimal. For the energy storage, although battery systems are well suited for short-term energy storage, hydrogen will be key for managing the longer-term variation. There is scope for further optimisation if the hydrogen can be produced from the otherwise curtailed wind power.

Renewable (Green) Hydrogen to Manage Wind Power Curtailment

Curtailment occurs when excess wind energy cannot be utilised or stored, leading to wasted potential. At present, electrons are stranded due to grid capacity limitations, that is not enough power cables from the generation areas to the user areas. For example, during high wind periods, wind farms in Scotland must turn down as they are producing more electricity than transmission capacity across the English border can carry. In the future, curtailment will continue to be required due to the over-generation capacity needed for grid stability.

Hydrogen production from electrolysis using surplus wind energy offers a pathway to add value. Electrolysis involves using electricity to split water into hydrogen and oxygen. When powered by surplus wind energy, this process can convert otherwise wasted electricity into hydrogen, a versatile and clean energy carrier. This hydrogen can then be stored and used for long term power grid balancing, as well as applications such as transportation and industrial processes. Further analysis will be needed to establish the optimum balance between the under-utilisation of wind turbines versus extra electrolyser capacity that could in turn be under-utilised if only used during curtailment periods.

Renewable (Green) Hydrogen Pathway

The UK government has recognised the potential of hydrogen and has set ambitious targets for its production. The UK Hydrogen Strategy aims to achieve 10 GW of low-carbon hydrogen production capacity by 2030, with at least half coming from electrolytic hydrogen. The UK government is working on policies to support hydrogen production and integration into the energy system with a “Low Carbon Flexibility Roadmap” due to be published this year, with new actions to drive clean power flexibility by 2030.

Infrastructure to enable renewable hydrogen is necessary; hydrogen production, storage, and distribution systems needs to be developed. This includes building electrolysis plants, storage facilities, and pipelines.

Projects are already underway to develop hydrogen production facilities across the UK with the support of the government funding and Kent is proud to be playing a key role in designing and building this infrastructure. Kent has completed Renewable (Green) Hydrogen conceptual studies, FEEDs and is currently working on the EPC for the first HAR project to get underway.

Innovation is needed to get Renewable (Green) Hydrogen happening in the UK. Areas for development include:

• Reducing the cost of electrolysers with technology advances and economies of scale.
• Blending hydrogen into the existing natural gas pipeline network and developing deblending technologies to separate hydrogen out again, enabling transition from natural gas to hydrogen.
• Investigating the potential to convert / adapt existing natural gas pipelines for hydrogen use.
• Developing salt cavern storage for hydrogen.
• Investing in hydrogen-ready power generation.
• Supporting emerging technology such as electrolysers with battery functionality.

Conclusion

With UK’s natural advantages of high winds (for power), an existing gas pipeline network (for repurposing) and geology (salt caverns), the UK is particularly well placed to use surplus wind energy to generate and store hydrogen. By converting excess wind energy into hydrogen, the UK can enhance its energy security, reduce carbon emissions, and create economic opportunities. As technology advances and costs decrease, hydrogen is poised to play a critical role in the UK's transition to a sustainable and resilient energy future.