Low Voltage (LV) flexibility: From "nice-to-have" to net zero necessity

The energy landscape has shifted. For years, flexibility on electricity networks below 11kV was treated as an optional experiment; a way to broaden the pool of flexible assets for Distribution Network Operators (DNOs). Beginning 2026, that luxury is evaporating.

Driven by the Warm Homes Plan and the Local Power Plan, the rapid rollout of solar PV and battery storage in social and low-income housing will turn LV flexibility into a core requirement for grid resilience.

The 2026 policy shift: Why "fabric first" faded

The UK government’s pivot in early 2026 was born of necessity. Following challenges in delivering solid wall insulation under the ECO4 scheme, the Warm Homes Plan redirected focus towards more cost-effective energy bill reduction measures: Solar PV and battery installations.

• The funding: Nearly £10 billion in grants and loans earmarked for home upgrades, including (but not limited to) solar PV and battery systems.
• The target: Over 50% of this funding is dedicated to low-income and social housing.
• The deadline: Full delivery by the end of 2030.

The technical bottleneck: Why energy networks are worried

While the policy ambition is high, the physical reality of the low voltage network is a bottleneck. Existing infrastructure was not designed for the massive reverse power flows that could be generated by thousands of social housing units exporting power simultaneously during summer peaks.

Key grid instability risks:

1. Lack of curtailment: Unlike large-scale solar farms, small-scale residential PV systems lack the sophisticated communication links for DNOs to curtail excess generation.
2. Inverter "sympathy" trips: G98 and G99-compliant inverters are designed to disconnect if voltage goes out of tolerance. In a dense estate, a minor fluctuation can trigger a chain reaction of disconnections, leading to localised grid instability.
3. The "connection denial" crisis: To avoid a blackout, DNOs are forced to deny new connection requests that risk supply exceeding demand on the LV feeder, directly jeopardising the 2030 targets.

From peak shaving to resilience procurement

To meet these challenges, DNOs must evolve. The Local Power Plan outlines how DESNZ, Ofgem, and NESO will collaborate to accelerate connections, but a key part of the technical solution lies in LV flexibility.

We foresee a broadening of approach from simple "flexibility procurement" (managing peak demand) towards Resilience Service Procurement. This involves:

• Active voltage management: Using domestic batteries to soak up local solar generation before it hits the transformer.
• Direct asset operation: A potential shift in license conditions that could allow DNOs to operate network-level batteries for resilience purposes.
• Cellular operation: Designing in resolution of resilience challenges locally, rather than with a central command and control approach.

Innovation in action: LCP Delta and Northern Powergrid

LCP Delta is currently pioneering several models of LV flexibility that balance the needs of the network with the benefits for the bill payer:

• Community DSO: Partnered with TNEI and Northern Powergrid, funded by Ofgem’s Network Innovation Competition, is an industry-first innovation project testing a cellular, community-led approach to distribution network operations.
• Resilient Customer Response: Partnered with CEE, PNDC and Northern Powergrid, explores how "islanded microgrids" can utilise customer-owned assets to protect vulnerable households during power outages.
• Social VPP: Partnered with CEE and Northern Powergrid is another Ofgem Strategic Innovation Fund (SIF) projects designing a community-owned Virtual Power Plant to support low-income customers while providing grid services.

These projects are demonstrating that flexible assets, principally batteries and EVs, can provide valuable services, but that to realise this fully requires stacking benefits that accrue to different parties: DNOs, communities and the wider energy system. This creates opportunities for new business models that enable these assets to be operated for mutual benefit.

The path forward

The transition to a cost-effective, resilient network requires DNOs to rethink their engagement with energy communities and third-party flexibility and resilience service providers. By moving flexibility closer to the source, we can turn a grid challenge into a community asset.