Green ammonia plant prototype powers up to tackle energy storage challenge

Engineers at the Science and Technology Facilities Council's (STFC) Energy Research Unit have switched on a new prototype facility that is designed to manufacture ammonia using renewable electricity, marking a significant advancement in the UK's green energy landscape.

The process offers a way to store previously unused generated energy in the form of hydrogen molecules within the ammonia. The hydrogen in the ammonia can later be extracted and used to generate electricity at a more useful and convenient time.

The ASPIRE (Ammonia Synthesis Platform using Intermittent Renewable Energy) plant is an innovative demonstration of technology that is capable of the flexible generation of green ammonia and the storage of hydrogen for future extraction.

The ASPIRE project was funded as part of the Department's £1 billion Net Zero Innovation Portfolio which provides funding for low-carbon technologies and systems and aims to decrease the costs of decarbonisation helping enable the UK to end its contribution to climate change.

This technology facilitates green ammonia synthesis from otherwise unused wind energy with a flexible approach that allows the generation of ammonia in accordance with the fluctuating availability and cost of the renewable energy supply.

Data collected from the operational plant will be crucial for future scaling efforts, ultimately enabling green ammonia to compete commercially with traditional fossil-fuel-based production.

This development comes at a critical time as the UK invests £1.1 billion for offshore wind - 'the backbone of the UK's clean energy mission' - to create a zero-carbon electricity system by 2030, part of the UK's broader commitment to reduce emissions by 81% by 2035.

In 2024, about one-tenth of all wind generated power in Great Britain was produced but not used, highlighting the opportunity for innovative energy storage solutions. Grid infrastructure continues to develop alongside the pace of wind expansion, and there are practical considerations around moving electricity from generation locations like Scotland to areas of high demand. Additionally, periods of low electricity demand during high wind output, and current limited energy storage options all contribute to the challenge.

The ASPIRE technology offers a versatile solution that not only addresses energy efficiency by utilising otherwise unused wind energy but also has the potential to:

• Decarbonise shipping and fertiliser manufacturing
• Provide grid resilience by converting this stored ammonia back to electricity during peak demand or when energy supply is low
• Supply low-carbon hydrogen for fuel via ammonia cracking

Green ammonia presents significant climate change mitigation through these applications, potentially delivering 10-15% of global CO2 emissions reductions.

ASPIRE also brings significant advantages over traditional ammonia production methods:

• Reduces 90% of the carbon emissions relative to conventional 'grey' ammonia production
• Reduces 70% of the carbon emissions of 'blue' ammonia production
• Scalable technology that can operate directly from renewable sources
• Ideal for integration with the UK's expanding renewable energy infrastructure
• Utilises low-cost electricity during periods of excess renewable generation
• Avoids carbon emissions penalties
• Not subject to volatile gas prices that affect conventional ammonia production

The UK's recent introduction of the Carbon Border Adjustment Mechanism (CBAM) and Hydrogen Allocation Round subsidies are expected to help overcome one of the key barriers to green ammonia adoption -- the current cost advantage of fossil fuel-based production.

Tristan Davenne, Principal Engineer at the STFC Energy Research Unit and ASPIRE project lead, explains: "Today marks the culmination of years of intensive research and engineering innovation. What makes ASPIRE notable is its ability to produce ammonia at variable rates and its readiness for scalability in industry. ASPIRE is not just a technical achievement - it is a practical solution that can transform unused wind energy from a challenge into a valuable resource. The data we gather from this operational plant will be invaluable as we work towards scaling this technology to make green ammonia compete with fossil-fuel-based production."

Energy Minister, Michael Shanks, said: “This government is working tirelessly to deliver homegrown, clean, secure power for the British people and technology like this showcases how British innovation can play a role in bringing down energy bills for good.  

"We are delivering the biggest upgrade in Great Britain’s electricity network in decades right now, which will minimise constraint costs and meet the capacity needed to deliver clean power by 2030."