Voltage management in the ED3 era

Why smarter voltage management is becoming essential for the future electricity network

The UK’s electricity distribution network is undergoing its biggest transformation in decades.

The rapid growth of electric vehicles, heat pumps, rooftop solar generation, battery storage and new sources of demand is fundamentally changing the way electricity flows through local networks. Distribution Network Operators (DNOs) are no longer managing predictable patterns of consumption. Instead, they must accommodate increasingly dynamic, decentralised and bidirectional power flows while maintaining network stability, reliability and power quality.

Against this backdrop, voltage management is evolving from a traditional compliance activity into a strategic capability for enabling network flexibility and supporting the transition to net zero.

Recent industry discussions, together with Ofgem’s emerging RIIO-ED3 framework, highlight a clear direction of travel: smarter, more responsive voltage management will play an increasingly important role in delivering a resilient, cost-effective electricity network.

From passive networks to active management

Historically, distribution networks were designed around predictable demand. Electricity flowed in one direction—from primary substations to homes and businesses—and voltage could largely be managed through conventional transformer tap changing and network reinforcement.

Today’s network operates very differently.

Local generation can raise voltage on lightly loaded feeders. Clusters of EV chargers can create sudden changes in demand. Heat pumps introduce new seasonal loading patterns, while battery storage systems both consume and export power.

As a result, voltage is becoming one of the primary operational constraints across many low-voltage networks.

Rather than simply maintaining statutory limits, network operators increasingly need the ability to monitor, control and optimise voltage dynamically in response to changing network conditions. This shift was a recurring theme throughout the Voltage Matters Forum, where speakers emphasised that voltage management is becoming central to unlocking additional network capacity and flexibility.

Unlocking more capacity from existing infrastructure

Traditional reinforcement remains an essential part of network development, but it is expensive, disruptive and often time-consuming.

Increasingly, the industry is looking first at ways of making better use of existing assets.

Smarter voltage management can help operators:

• release additional hosting capacity
• reduce voltage constraints
• support the connection of low-carbon technologies
• defer or reduce traditional reinforcement
• improve utilisation of existing network infrastructure.

This concept has been described as unlocking the network’s “hidden battery”—making greater use of flexibility that already exists within the distribution system before investing in new physical assets.

From innovation projects to business as usual

Over the past decade, many DNOs have successfully demonstrated advanced voltage management through innovation programmes such as CLASS, Smart Street and other flexibility trials.

The industry’s focus is now shifting.

Rather than asking whether these approaches work, attention is turning to how proven technologies can be deployed at scale as part of day-to-day network operation.

This transition—from innovation funding to mainstream operational deployment—was highlighted repeatedly during recent industry discussions. The challenge is no longer proving the concept; it is integrating successful solutions into routine network planning and operation.

What ED3 means for electricity distribution

Ofgem’s developing RIIO-ED3 framework reflects many of these emerging priorities.

The emphasis is moving towards networks that are:

• more flexible
• more digital
• better coordinated
• capable of supporting faster decarbonisation
• able to maximise the value of existing infrastructure.

Voltage management sits at the centre of many of these objectives.

Rather than being viewed solely as an efficiency measure, active voltage management is increasingly recognised as an important tool for increasing network capacity, supporting flexibility markets and enabling greater uptake of low-carbon technologies.

Visibility and control at the edge of the network

One of the strongest messages emerging from industry discussions is the need for greater visibility of low-voltage networks.

Historically, DNOs have had limited real-time information beyond primary substations. As distributed energy resources continue to grow, improved visibility and local control become increasingly important.

Future networks will require technologies capable of:

• monitoring changing network conditions
• responding dynamically to local voltage variation
• supporting independent phase management
• integrating with wider network management systems
• providing scalable solutions that can be deployed across the distribution network.

These capabilities allow operators to respond proactively rather than relying solely on reinforcement once constraints have already developed.

Where powerPerfector iQ fits

powerPerfector iQ has been developed specifically for this changing operating environment.

Using active closed-loop voltage control and independent management of each phase, the system continuously regulates voltage in response to real-time network conditions. Rather than applying a static reduction, iQ dynamically maintains target voltages while accommodating phase imbalance and changing demand.

This approach supports many of the priorities emerging across the electricity distribution sector, including:

• improving voltage performance on constrained low-voltage networks
• supporting increased EV charging and heat pump deployment
• enabling greater integration of distributed generation
• improving downstream power quality
• helping operators maximise the utilisation of existing assets.

As the industry moves towards more active distribution system operation, technologies capable of delivering responsive, scalable voltage management are likely to play an increasingly important role.

Looking ahead

The transition to net zero is changing the role of electricity distribution networks.

Success will depend not only on building new infrastructure, but also on making existing networks smarter, more flexible and better able to accommodate changing patterns of generation and demand.

Voltage management is becoming a strategic enabler of that transition.

Industry discussions, innovation programmes and the emerging RIIO-ED3 framework all point towards the same conclusion: actively managing voltage is no longer simply about remaining within statutory limits. It is about unlocking capacity, improving network flexibility and supporting the electricity system of the future.

powerPerfector believes technologies such as iQ can make an important contribution to that journey, helping Distribution Network Operators respond to today’s challenges while preparing their networks for tomorrow.