Reduce a busy period
When many homes draw power at once, batteries could supply part of their own homes’ demand for a short time. That lowers demand seen by the grid without asking people to stop using electricity.
The idea behind ShareVolt
Why flexibility matters.
A flexibility event is a short, planned change in electricity use or supply. It may be needed when demand peaks, renewable power is plentiful, or part of the network is under pressure. Home batteries could help at those moments—and create value for households and the wider system.
Why an event may occur
The grid does not need the same response all day.
Electricity supply and demand must stay in balance, and network equipment has capacity limits. An event would have a specific purpose, a defined time window and a requested change. These are four reasons one might be called:
Use power when it is abundant
When wind or solar output is high relative to demand, eligible batteries could charge earlier, subject to the right controls and commercial arrangements. This may help make use of renewable electricity that might otherwise be constrained.
Ease a pinch point
A transformer or cable can be busy even when the wider system is comfortable. A response from homes in the relevant area could help manage that local limit at the required time.
Respond when value is needed
A pilot may run a controlled test. At scale, an energy price difference could create a trading opportunity, or a system operator could request a service. Each would have its own timing, rules and required response.
What happens during an event
Move some demand in time.
One possible pattern is to charge a battery when electricity is plentiful, then use that stored energy at home when grid demand is higher. A particular event might involve only one part of this pattern, depending on what the system needs.
Renewable output rises
A battery can charge when suitable electricity is available and its own settings allow it.
Energy waits
Storage moves some electricity use to an earlier time instead of requiring all of it at the moment of demand.
Demand rises later
A battery may supply some of its stored energy to the home, reducing grid demand for a short period.
Illustrative example only. Charging and discharging lose some energy, and a battery cannot respond if doing so would breach its reserve or device limits.
Who benefits, and how?
A useful event should create more value than it costs.
The value can come from a better time to use or trade electricity, avoiding a more expensive grid response, and making more use of renewable generation. ShareVolt’s aim is to build a model in which homes share in that value as the service grows.
Share in the value your battery creates
A day/night tariff can already create an opportunity to charge at the lower night rate and use that energy later. If the pilot proves the service and a market route is secured, ShareVolt aims to offer compensation for making an agreed part of a battery available and for delivering a response when called, where the service supports both types of payment. The terms would be set out before participation.
Reduce the cost of running the grid
A coordinated response can help manage peaks and local constraints, reducing reliance on more expensive interventions and, in some cases, deferring network upgrades. That contributes to more efficient grid running costs over time, which benefits electricity users across Northern Ireland.
Put more clean electricity to work
Charging when renewable output is plentiful and supplying the home when the grid is under greater pressure can help use more wind and solar power and reduce reliance on fossil generation. We would choose events for a clear system purpose, then measure the response and its environmental impact so the service keeps improving.
How a home could earn: retail day/night savings are one route today. As the fleet grows, value could also come from wholesale energy trading and later from qualified system services. The aim is to share that market value with participants through clear terms that account for energy costs, battery losses and use.
The home also benefits from keeping its chosen reserve. The pilot must show that any event leaves enough energy for that household’s needs.
The engineering
Many small batteries can act as one useful resource.
A single home battery is small compared with a grid. ShareVolt would need to combine enough compatible batteries into a measurable, reliable fleet before seeking access to wholesale energy-market opportunities or system services. Each home would contribute only within its available limits.
Check availability
Before an event, the system would check recent device data, charge level, connectivity and the home’s chosen reserve.
Coordinate a response
Eligible batteries could be asked to charge, pause charging or reduce grid demand for a limited period, according to the event and device capability.
Measure what happened
Commands alone are not evidence of impact. The pilot would compare intended actions with actual device response and report what it can verify.
The Northern Ireland route
Start with homes. Build towards markets.
For NI households, the familiar time-based retail option today is a fixed day/night tariff. That can reward moving battery charging to the night rate, but it is different from trading the changing wholesale electricity price. ShareVolt’s wider opportunity depends on proving that many batteries can be coordinated as one dependable resource.
Prove the fleet
Demonstrate safe control, accurate measurement, reliable availability and a useful response from a growing group of homes.
Capture price differences
With enough scale and the right market access or partner, an aggregated fleet could store energy when wholesale prices are lower, then use it at home or export it where permitted when it is more valuable.
Support grid operation
Once the fleet meets the relevant technical and market requirements, it could seek opportunities to be available for—and deliver—services requested by the system operator.
This is the route ShareVolt wants to develop after the pilot establishes what the fleet can reliably deliver.
Home first
Flexibility has boundaries.
The plan is to respect each battery’s manufacturer limits and the minimum charge a homeowner wants to keep. If a device is unavailable, data is stale or a proposed action fails the safety checks, it should be left out of that event.
Reserve protectedThe home keeps its chosen minimum battery level.
Device limits respectedActions stay within the manufacturer’s supported capabilities.
Evidence checkedThe pilot must measure response before claiming any grid or climate benefit.
What the pilot is for
Test the idea. Report the results.
ShareVolt aims to learn which batteries can participate reliably, how much flexibility is available, and what a coordinated response actually delivers. This evidence would help us build the scale, market access and fair compensation model needed for a longer-term service. We would also measure costs and environmental outcomes so that future events are chosen for real value.
Help shape the pilot.
Registering interest is a way to tell us what technology you have. It does not commit you to participate.
Further reading
See an example NI day/night tariff, SEMOpx’s day-ahead and intraday markets, SONI’s system services, and NIE Networks’ flexibility strategy. ShareVolt’s pilot, market route and compensation model are aims under development.