Net zero and the energy system transition

The OptiSTORE project seeks to address the challenge of supply and demand imbalance within Wales & West Utilities’ (WWU) network as means to mitigate the need for storage particularly in support of Net Zero ambitions including the planning for development of new hydrogen pipelines and WWU’s existing HyLine programme.. Current geological hydrogen storage methods such as salt caverns saline aquifers and depleted oil and gas reservoirs are capital intensive often technically complex and reliant on specific geological conditions which are less present across WWU’s geography.

Whilst hydrogen can be stored as a liquid this process requires extremely low temperatures which is technically complex and costly due to the energy required to maintain such low temperatures. One promising alternative to this is Ammonia which is attractive due to its lower storage temperature (-33°C versus -253°C for hydrogen) higher volumetric energy density and existing infrastructure and regulatory familiarity.

This project will explore the feasibility of using ammonia as a means to provide supply-side flexibility of hydrogen to support industrial clusters and future hydrogen pipeline developments.

This project advances lined rock caverns (LRCs) as a flexible hydrogen storage solution in WWU’s area by moving from regional screening to site‑specific pre‑feasibility. It refines geology and site availability shortlists candidate sites in South Wales and South West England conducts a detailed pre‑feasibility study with borehole core analysis at a priority site and assesses commercial models and funding routes culminating in a final report to inform decisions on progressing to full feasibility.

This assesses the suitability of WWU’s three high-pressure gas storage vessel sites (Weston-super-Mare Cheltenham and Bristol/Stapleton) as a case study where learning can be applied to relevant GB networks for hydrogen service. The work includes materials characterisation hydrogen embrittlement testing analysis of 100% hydrogen and 5%/20% hydrogen blends assessment of capacity and pressure requirements evaluation of the implications of removing the vessels entirely and down-selection of viable liner materials and application methods. The project will produce site-specific evidence a shortlist of feasible liner options and clear engineering recommendations to maintain required capacity and pressure envelopes under hydrogen scenarios.

The UK Government has identified Carbon Capture Utilisation and Storage (CCUS) as a critical enabler of industrial decarbonisation committing £20 billion to early deployment and targeting 20-30 MtCO₂ stored annually by 2030. Much of the UK’s industrial emissions are geographically concentrated opening the door to targeted CCUS clusters that can deliver outsized impact. GDNs are well positioned to play a meaningful role in this emerging ecosystem.

In Carbon Networks Phase 1 Blunomy assessed the strategic fit between CCUS and the GDN business model. The study identified a range of potential roles including local CO₂ collection participation in transport and storage networks and support for blue hydrogen and CO₂ utilisation initiatives – and it highlighted the importance of early positioning to shape regulatory and commercial pathways.

Phase 2 aims to build on this foundation and move from conceptual framing to actionable insight. Blunomy in the next stage will explore specific industrial opportunities within SGN’s and WWU’s footprint engage with project developers and clusters and outline potential pilot activities. Alongside this the work will assess how CCUS participation aligns with SGN’s broader priorities and the implications for regulatory engagement and investment planning.

Following the successful completion of Blending Implementation Plan (BIP) Phase 1 (Planning) in 2023 and BIP Phase 2A (Design) in 2025 the gas networks have engaged KPMG to proceed with the next phase of the programme BIP Phase 2B (Delivery).

Running from February 2026 to November 2026 and focusing on Market Frameworks impacts Phase 2B is required to build on the consensus achieved in Phase 2A and close out all implementation areas that require joint-decision making by the networks. These decisions pertain to detailed design of the application window and industry governance. The outcomes of Phase 2B will create a clear and consistent pathway for individual networks to support the application window and connections process alongside addressing common areas of industry governance based on collective decision making to meet timelines of future HAR.

Biomethane is key to decarbonising the UKs gas network. However in comparison to Natural Gas it has a lower energy density and requires enrichment before injection into the gas network. Currently Propane is used a fossil fuel undermining the environmental credentials of biomethane increasing production cost and introducing bituminous elements causing down-time in biomethane plants. Project CLEAN GREEN will identify alternative green enrichment gases to fossil Propane and consider how improved measurement technology can inform network intelligence to optimise Biomethane injection. This will lead to improvements in cost carbon efficiency and injection volumes of Biomethane into the distribution networks.

The use of greener gases such as biomethane are an important part of the UK’s transition to net zero. Underground storage sites for biomethane are critical for balancing seasonal supply and demands for energy. However increased levels of oxygen in biomethane can lead to corrosion of assets in wet gas conditions compromising the integrity of storage facilities. This project assesses in a comparative analysis the technical and economic viability of advanced catalytic and adsorption technologies to reduce oxygen levels in biomethane with corrosion inhibitors to ensure the integrity and longevity of critical storage infrastructure.

This project will produce reports that will compare the Asset Interventions Database vs their asset base to provide an estimated readiness rating and confidence level against the gas networks assets for the conversion to hydrogen both 100% and blended.

The work will develop a pathway for the biomethane sector to monetise CO2 and identify the role the gas networks can play reducing the long-term cost of gas decarbonisation.

The consultant will deliver a report demonstrating the Gross Value Added (GVA) benefits of biomethane and jobs created and/or maintained from greater biomethane generation across upstream midstream and downstream and the particular benefit provided to GB’s rural communities.

This will be a build on the Economics of Biomethane project conducted by Baringa for the Taskforce and would be expected to leverage analyses and modelling from that project as required.

This analysis is to form the basis of a compelling report making the case for greater biomethane production and injection into the GB gas networks. This report to include recommendations for the target audience which includes Government Treasury DESNZ DEFRA Local authorities etc.

This is a project being delivered in collaboration with the Green Gas Taskforce.