Scottish and Southern Electricity Networks (SSEN) announced on 16 September 2025 that it has started real-world trials of its Electricity Supply Checker, a tool that tells households whether their property's electricity connection can support low-carbon technologies such as heat pumps and electric vehicle chargers1. Households in two selected parts of SSEN's licence areas, in Swindon and South Oxfordshire, are now being sent letters about the Checker and directed online to look up their property's readiness1.
SSEN says its studies and modelling conclude that around 516,000 of its customers have connections likely to need some form of upgrade1. The Checker draws on a range of data to report the estimated capacity available to connect low-carbon technologies, examples of what could be connected at a particular property given that capacity, and whether upgrades or de-looping will be needed1. De-looping is described as the splitting of a supply currently shared between two separate properties1.
SSEN said the two trial areas were chosen for their diverse geography, degree of readiness and housing stock1. The tool's development follows research by project partner +Impact into the need for such a solution, and SSEN describes the work as now moving into a new phase with the start of trials in specially selected suburban and rural areas1.
"We've begun trialling a clever new tool which will let households know if their property can support the installation of new, efficient Low-Carbon Technologies like heat pumps and EV chargers."
Richard Hartshorn, SSEN's Low-Carbon Technology Readiness Manager, said the company has commitments in the current price control period to support substantial growth in the number of electric vehicles and heat pumps on its network, and that many homes were built before heat pumps and EVs were thought of, so in many cases upgrades will be needed1.
| What the Checker reports | Detail given by SSEN |
|---|---|
| Available capacity | The estimated capacity available to connect low-carbon technologies1 |
| What could connect | Examples of low-carbon technologies a property could support given that capacity1 |
| Work needed | Whether upgrades or de-looping will be needed1 |
Why it matters for households
A heat pump or a high-power EV charger can draw far more current than the connection was originally sized for, and the cost and disruption of an upgrade usually only surface once an installer surveys the property. The Checker is intended to give that visibility earlier, so a household can find out whether its supply is ready before committing to a technology1. SSEN gives the example of a household that learns an upgrade is needed and can then have the work done in advance, at a time that suits them, rather than facing an unexpected upgrade when an existing gas boiler needs replacing1. For a home's energy independence, the practical question is whether the connection can carry the load: a supply that cannot support a heat pump or charger limits what a household can run from its own electricity, whatever else it installs. SSEN has not reported how many households will be included in the trials, what the trials will cost, or when the Checker might be offered outside the two trial areas1.
What happens next
Households in the selected areas of Swindon and South Oxfordshire are being sent letters now, directing them online to check their property's readiness and to proceed with upgrades if required1. SSEN says its teams will be on hand to help those households through the upgrade process1. No end date for the trials and no date for a wider rollout have been reported1.