Voltage management just grew up. Now DNOs need to show their working.
For years, voltage management has been a quiet technical topic for engineers, largely invisible, and rarely talked about at parties (not even the ones I go to). Ofgem’s recently published ED3 Sector Specific Methodology Decision has changed that. Voltage management is now a proper DSO responsibility, with a mandatory published strategy and annual reporting.
At Smart GB, with the Energy Geeks, and through the Voltage Matters Forum, we lobbied hard for this and the consequential Grand Slam of benefits. Better value flex; easier and more reliable connections; lower customer bills; and reduced blackout risk. So I’m quietly pleased, before getting to the bit where the real work starts.
Where the SSMD is genuinely good
Three things stand out. First, voltage management is no longer an optional Directly Remunerated Service for flexibility that almost nobody took up. It is a core function and will deliver lower-cost flex using assets customers have largely already paid for. Second, the average delivered voltage metric we pushed for is now a required reporting line. Third, conservation voltage reduction has its own outcome aimed squarely at cutting customer bills. The scandal of running the electricity system for the convenience of the networks, but at a cost to customers should soon be over. Lower voltages, lower bills, fewer EV chargers disconnecting. Customers win.
That’s a good decision. Credit where it’s due to Ofgem.
Where DNOs need to go further
Here’s the catch. Ofgem has set the direction but left the steering to the DNOs, and that’s where strategies will be made or quietly fudged.
The decision requires DNOs to report their average delivered voltage. It does not set a codified target. DNOs are asked to determine their own “reasonable” average voltage reduction per network area. Reporting a number across a whole region is not the same as committing to move it as low as practicable at each substation. So the obvious nudge for the DNO Voltage Management Strategies being submitted with their business plans: don’t just measure the voltage, tell us where you’re reducing it, what you are taking it to and by when.
The incentive picture is also unfinished. Ofgem is still ‘considering’ which aspects to reward, and I know from experience that a reporting duty without a sharp signal behind it tends to drift. So this one cuts both ways: DNOs need strong, specific strategies now, and Ofgem needs to land the incentive design rather than leave it idling until ED4.
Hence, three friendly asks for the December strategies: set genuine, localised average voltage reduction targets, not just baselines; be concrete about the LCT headroom you’ll unlock; and show the trade-offs with losses and reinforcement honestly.
Come and argue with us in person
If you want to thrash this out properly, the Voltage Matters Forum Live is in Birmingham on 25 June. We have all five DNOs and Ofgem confirmed in the room, which is either a once-in-a-career meeting of minds or a lively day, possibly both.
Bring your voltage strategy thinking. Bring your scepticism. We provide the refreshments.
[Register here: https://www.eventbrite.co.uk/e/voltage-matters-live-2026-tickets-1988821765438]