Britain’s electricity system is changing quickly. More homes and businesses are installing solar PV, EV chargers, heat pumps and other new technologies. Many of these connect at low voltage (LV), and often in the same areas. This makes voltage management increasingly important. If voltage can’t be managed well, it can slow down new connections and lead to higher costs.
That is why the Energy Networks Association (ENA) is consulting on modernising statutory voltage limits in Great Britain. The aim is to give network operators more flexibility at the lower end of the voltage range. Done well, this could create more “headroom” for low-carbon connections and reduce the need for avoidable reinforcement — while still maintaining supply quality and protecting customers.
Our view, in brief
The Independent Networks Association (INA) supports the change in principle, but only if it is implemented safely and transparently. In our submission, we:
- support the change in principle, with safeguards and ongoing review
- support a phased approach, with clear monitoring, review criteria and mitigation
- expect issues to be investigated quickly using available voltage and smart meter data
- emphasise that Guaranteed Standards of Service (GSoS) still apply where voltage is outside the statutory range
- ask for clear detail on implementation, including the need to adjust the 11kV voltage range so the LV benefits are realised
What is being proposed?
The consultation proposes changing the lower statutory limit for low-voltage supplies by moving from 230V +10% / −6% to 230V +/-10%. In practice, that changes the lower limit from 216.2V to 207V (the upper limit stays the same).
Network operators also propose lowering operating voltage in small steps:
- 1% in year one, followed by
- a further 1% in year two, subject to review
Why this matters
Voltage constraints can limit how much new generation and demand can connect, especially at low voltage. If networks can operate safely across a wider statutory range, and if operating voltage is reduced in a controlled way, that can make it easier to connect:
- more rooftop solar and other distributed generation
- more EV charging
- more low-carbon heating and new demand
In the right situations, this can reduce the need for reinforcement and support quicker, lower-cost connections.
For customers — including developers and commercial connection users — the outcome that matters is simple: reliable networks, delivered quickly, with transparent costs and clear accountability.
Modernisation must protect customers
Changes like this need strong governance. Customers don’t experience “voltage” as a policy concept — they experience it through the performance of their equipment and the quality of their supply. Any changes must be implemented in a way that protects customers and deals quickly with any problems.
That is why a phased approach must be backed by clear information on:
- how voltage performance will be assessed
- how impacts will be reviewed before moving to the next phase
- how adverse impacts will be identified and mitigated
Handling customer issues
If customers report issues that may relate to voltage, network operators should investigate promptly. This should include using voltage and smart meter data to check whether the network is the cause, and taking corrective action where needed.
We also note that GSoS apply where voltage is outside the statutory range. While queries may increase during implementation, we would not expect any derogation from GSoS.
Making sure the benefits are realised in practice
There is also a practical question: will the change deliver the benefits in the real world, not just on paper?
If the aim is to manage LV voltage differently, the operational approach needs to be consistent across the network. A key point in our submission is that implementation should include clear instruction on 11kV settings, including the 11kV voltage range at 11kV, so the whole network voltage is shifted and the new range can be used properly. Without this, the extra LV headroom — especially for solar PV and EV charging connections — may not be fully realised.
Keeping standards and guidance aligned
Statutory voltage limits are only one part of the picture. If the rules change, the supporting standards and guidance used by designers, installers and operators also need to keep pace. Over time, ENA guidance and relevant industry standards should be reviewed and updated so they align with any new statutory requirements.
Getting the balance right
Modernising statutory voltage limits could help connect low-carbon technologies faster and reduce avoidable network costs. But it will only build confidence if it is implemented carefully, transparently and with strong customer protections.
That balance matters for the whole sector — including IDNOs delivering last-mile infrastructure on new developments. We all benefit from reforms that enable faster connections while maintaining high standards of supply quality, customer service and accountability.
