Triad Avoidance and Triad Charges: What Changed in 2023 and What to Do Now?

For over a decade, Triad avoidance was one of the most effective ways for energy-intensive manufacturers to reduce electricity network costs.

By lowering demand during winter peak periods, businesses could significantly reduce their annual TNUoS charges.

The last Triad period was 28 February 2023. The strategy is gone. Yet many businesses are still operating as if Triad charges still exist.

If your energy manager is still monitoring for Triad alerts, halting production lines, or paying shift premiums to reduce demand at peak times, this article is for you.

What were Triad charges?

Triad charges were a mechanism used to recover part of the cost of maintaining the national high-voltage electricity transmission network.

These costs, known as TNUoS (Transmission Network Use of System) charges, were partly allocated based on how much electricity a site consumed during the three highest-demand half-hour periods of the winter season, running from November to February each year.

Those three half-hour periods became known as the Triads, and for many energy-intensive businesses, Triad avoidance became a core part of the energy management calendar.

Here is a full explanation of how TNUoS works and how it affects your electricity bill today.

How much could businesses save through Triad Avoidance?

The financial case for Triad avoidance was compelling enough that many businesses built operational processes around it.

The saving was directly linked to a site’s Triad demand, meaning the amount of electricity being drawn from the grid during each of the three qualifying half-
hour periods.

In practical terms, the more demand a site could lose during a suspected Triad event, the lower its locational TNUoS charge would be for the following year. For sites with a high agreed supply capacity and consistent production schedules, the sums involved were substantial.

To capture these savings, businesses would receive Triad alerts from their energy consultant, broker, or a specialist forecasting service. On receipt of an alert, site managers would reduce electrical load, pausing energy-intensive machinery, running generators, dimming non-essential lighting, or cutting production where operationally possible.

What is the Targeted Charging Review and why did it end the Triad era?

The Targeted Charging Review (TCR) was an Ofgem-led review of how electricity network costs are recovered from businesses and households. It concluded that the existing system created distortions in the market and placed an unequal burden on those who could not easily adjust their demand.

Ofgem’s view was that the system unfairly rewarded businesses that could quickly reduce demand, while sites with less operational flexibility ended up carrying more of the network cost instead.

The solution was to move the majority of TNUoS cost recovery onto fixed residual charges, based primarily on agreed supply capacity rather than actual behaviour during peak periods.

The result was that approximately 90% of TNUoS charges were shifted to a fixed basis, removing the financial incentive for demand flexibility through Triad avoidance.

This came into effect in April 2023. From that point, reducing demand during what would previously have been a Triad avoidance event produces minimal or no financial benefit for many sites.

A small portion of TNUoS charges still uses the old Triad methodology in some regions, but the value is now so low (approximately 3% of total costs) that most businesses no longer gain anything meaningful from reducing demand during peak winter periods.

Are you still running a dead protocol?

This is a question worth asking honestly. Triad avoidance protocols were built into the operational running of many manufacturing sites over many years. Shift patterns, production schedules, and energy management systems were all adapted to respond to Triad alerts. Those changes did not automatically reverse when the TCR came into effect.

In practice, that means some businesses are still:

• Paying for Triad forecasting or alert services that now serve no financial purpose
• Halting or curtailing production in response to peak demand signals that no longer trigger any cost reduction
• Paying overtime, standby rates, or shift premiums to reduce load during events that carry no financial benefit
• Carrying the operational cost and disruption of demand reduction with negligible or no financial return

These were rational responses to a genuine cost-saving opportunity. But that incentive is gone, and continuing to act on it is costing businesses in wasted
resource, unnecessary disruption, and the opportunity cost of not redirecting that effort towards strategies that still work.

Three modern alternatives to Triad avoidance

The good news is that the flexibility and discipline that made Triad avoidance work can be redirected into strategies that deliver real financial returns under the current network charging framework.

1. Capacity optimisation
   Under the current TNUoS framework, charges are based on your agreed supply capacity, the maximum kVA level agreed with your Distribution Network Operator (DNO). Many businesses could be paying for more capacity than they use.
   
   Reviewing and renegotiating your agreed kVA downwards, where your actual demand profile supports it, can deliver a direct and ongoing reduction in fixed network charges. This is a structural saving that requires no operational disruption and no ongoing monitoring.
   
2. Demand Side Response (DSR)
   Demand Side Response schemes pay businesses to reduce or shift their electricity demand at grid stress events, specifically, Balancing Mechanism calls and National Grid ESO flexibility events.
   
   These are not Triad periods, but structured flexibility markets where the grid operator needs demand reduction at short notice. Unlike Triad avoidance, DSR generates direct revenue.
   
   Eligibility and payment rates vary depending on the scheme and your site’s load profile, but for manufacturers with interruptible processes, this represents a credible income stream rather than simply a cost-avoidance mechanism.
   
3. Battery storage
   On-site battery storage allows businesses to charge at times of low grid demand and low electricity prices, then discharge during peak periods when unit rates are higher. This can reduce exposure to time-of-use pricing and support participation in flexibility markets.
   
   For sites with significant daytime consumption and access to overnight cheap-rate tariffs, storage can deliver meaningful cost reductions and the economics are not dependent on regulatory frameworks that may change.

A note on TNUoS charges in 2026

It is also worth noting that TNUoS charges increased in April 2026, following the start of the RIIO-ET3 regulatory period.

For many manufacturing businesses, this has meant an increase on their annual electricity bill.

If you’re unsure whether your site is still carrying outdated Triad avoidance processes, Tritility can review your current setup, identify where costs are still being incurred, and assess which modern flexibility strategies are actually worth pursuing.

Book a free invoice audit to find out more.