This project will assess the potential for assets connected to distribution networks at or below 132 kV to provide stability services to the transmission system and participate in future NESO Stability Markets. It will engage DNOs and industry stakeholders to identify suitable asset types, operational constraints and data requirements. An integrated RMS/EMT modelling approach will assess contributions to inertia and short-circuit strength and compare performance with existing transmission-connected providers. Outputs will include a technical benchmark, capability map and evidence base identifying where these assets could provide effective stability services, suitable conditions and potential barriers. Findings will inform future service design, eligibility criteria, procurement approaches and potential trials. Key risks include data availability, model integration, protection, voltage, congestion and curtailment.
Benefits
What is the expected benefit from completing this project?
The primary direct benefit is knowledge and understanding. The potential full-scale benefits are Financial, Environmental and Social, enabled by the knowledge generated through the project. The project will create a robust evidence base showing whether, where and under what conditions distribution connected assets below 132 kilovolts (kV) can provide effective stability services towards the transmission system. This will give NESO a clearer technical basis for future Stability Market eligibility, service design and procurement decisions.
Who will benefit from this project and in what way? NESO will benefit from improved knowledge of how inertia and short-circuit strength from lower-voltage assets propagates through distribution networks and contributes to transmission-level stability. DNOs, OEMs, aggregators, developers and asset owners will benefit from clearer evidence on the technical and operational requirements that may apply to future participation in Stability Markets. Consumers and NESO may benefit indirectly because the project will help identify whether a wider pool of providers could enable more efficient future procurement and avoid unnecessary reliance on higher-cost solutions.
How confident are you this project will deliver this benefit? High for the Knowledge benefit, because the direct benefit is within the control of the project scope.
Can this benefit be quantified? The project will provide measurable outputs, including the number of voltage levels assessed, the number of GB zones screened, the range of asset operating levels tested, priority EMT cases completed, and clear recommendations for future trials or market design. Financial, Environmental and Social benefits cannot be fully quantified at this stage. These depend on the modelling results, the number and type of assets shown to be technically suitable, the extent of DNO constraints, and any future market design choices made after the project.
What is the expected benefit if this idea is implemented at full scale?
If implemented at full scale, the learning from this project could enable a wider range of distribution-connected assets to participate in future Stability Markets where they can provide reliable value, increase competition and reducing reliance on a narrower pool of transmission-connected providers. Environmental benefit: It could support a more efficient transition to a low-carbon electricity system by enabling suitable low-carbon or distributed assets to provide stability services. Social benefit: It could support consumers through more efficient, resilient and inclusive market access to stability services.
Who will benefit from this project in the future and in what way? Consumers could benefit through more efficient stability procurement if technically capable lower-voltage assets increase competition and reduce whole-system costs. NESO could benefit from a broader set of stability service options and clearer eligibility criteria for future procurement. DNOs could benefit from a more structured understanding of the operational coordination, data exchange and protection requirements needed to support distribution-connected service provision. Asset owners, developers, OEMs and aggregators could benefit from clearer routes to market and more transparent capability requirements, supporting fairer access to future Stability Market opportunities. The wider energy system could benefit if suitable low-carbon or distributed assets are enabled to contribute to system stability and support decarbonisation.
What needs to happen for this future benefit to be realised? To realise the knowledge benefit, the project findings need to be reviewed and accepted by relevant NESO teams. To realise the Financial benefit, follow-on activity may include targeted DNO-region pilots, service trials with selected assets below 132 kV, procurement readiness assessment, and refinement of service definitions and eligibility criteria. To realise the Environmental benefit, suitable low-carbon or distributed assets would need to be confirmed as technically capable and incorporated into future service design where they can provide reliable value. To realise the Social benefit, future arrangements would need to provide transparent participation requirements and avoid creating unnecessary barriers for capable providers.
How confident are you this project will deliver this benefit? Medium overall. Confidence is high that the project will deliver the enabling knowledge benefit, but confidence in the future Financial, Environmental and Social benefits is medium because they depend on the technical findings, stakeholder appetite, DNO data and coordination arrangements, future policy and procurement decisions, and whether follow-on trials or implementation activity confirm that distribution-connected assets can reliably deliver the required service.
Can this benefit be quantified? Knowledge benefits can be partially quantified through measurable project outputs such as voltage level are assessed, GB zones screened, asset operating levels tested, priority EMT cases completed, and recommendations produced. Financial benefit cannot be quantified at this stage; potential future metrics include changes in procurement costs, avoided reliance on higher-cost transmission-connected solutions and additional stability service capacity made available. Environmental benefits cannot be quantified at this stage; potential future metrics could include the number of low-carbon or distributed assets enabled to participate and any associated carbon benefit. Social benefits cannot at this stage; potential future indicators could include number of eligible asset classes, increased provider diversity, improved transparency of market requirements and any resilience or consumer value improvements from broader market participation. The project will provide the evidence needed to support quantified estimates in a subsequent implementation or trial phase.
