IN Brief:
- EDF and Duracell Energy are running a three-month trial using around 50 residential battery systems in England.
- The batteries will participate in local flexibility markets and respond to distribution system operator signals.
- The trial tests how domestic storage can be aggregated into a network-facing flexibility resource.
EDF and Duracell Energy are running a three-month trial to test how residential battery systems can participate in local flexibility markets.
The project involves around 50 Duracell Energy home battery systems across England. The batteries will be coordinated to respond to distribution system operator signals, with EDF managing local market participation, tender selection, dispatch strategy, and market operations.
Puredrive Energy, the authorised licensee and manufacturer of Duracell Energy home battery products, is handling customer recruitment, onboarding, and participation. The trial is running from June to August 2026 and will support the development of future grid services propositions.
Domestic battery systems are becoming more common as households adopt solar PV, time-of-use tariffs, and electric vehicles. Many are installed for bill optimisation or solar self-consumption, but their ability to charge and discharge at specific times also gives them potential value to the local network.
Aggregation is the central engineering and operational challenge. One home battery is too small to affect a distribution constraint in any meaningful way, but a coordinated fleet can provide measurable capacity if the assets are visible, available, and controlled reliably. The network requires response at a defined location and time, not a general estimate of installed domestic storage capacity.
That requirement places a heavy burden on communications, forecasting, and dispatch systems. Each battery has its own state of charge, household load pattern, customer preference, and connection characteristics. A flexibility provider must coordinate those variables while ensuring that customers do not lose the primary benefit they expected from installing the system.
Local flexibility markets are still developing the processes needed to make these smaller resources useful at scale. Common dispatch standards, clearer performance verification, and more consistent market interfaces are essential if residential batteries, EV chargers, heat pumps, and other distributed assets are to participate without excessive administrative cost.
The trial sits alongside wider work to release capacity from the low-voltage network. Transformer retrofit projects are testing how existing assets can be operated more effectively as EV chargers, heat pumps, and solar generation create new load patterns and phase imbalance. Domestic flexibility addresses the same capacity problem from the customer side of the meter, using controllable demand and storage rather than physical network upgrades alone.
Residential storage will not remove the need for reinforcement. Electrification will still require new cables, transformers, substations, automation, monitoring, and protection upgrades, particularly where demand growth is sustained rather than occasional. Aggregated batteries can, however, help manage peak conditions and defer some interventions where constraints are limited to specific hours or seasons.
The commercial model depends on creating value for both the network and the customer. A household battery owner may accept third-party control if payments are clear, participation is simple, and the battery still supports domestic energy needs. Poorly designed propositions risk undermining customer confidence, especially if dispatch events interfere with self-consumption, backup settings, or expected savings.
For network operators, the trial will be useful only if performance can be measured accurately. Dispatch success, response duration, communications reliability, available capacity, and settlement accuracy will determine whether aggregated domestic storage can move beyond pilot projects. A fleet of small batteries can become a useful grid resource, but only when it behaves predictably under operational conditions.
The EDF and Duracell Energy project gives residential storage another test in local flexibility markets at a point when the edge of the grid is becoming more active. As domestic energy assets multiply, the ability to coordinate them safely and fairly will become a defining part of distribution network operation.
