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How to minimise the impact of Triad costs on your organisation this winter

Those of you who follow energy trends closely will be aware that we’re already into the latest Triad season. The Triad season falls during the winter months, from the start of November to the end of February, and reflects the higher demand seen from both industrial and retail customers at this colder, darker time of year.

Triads are simply the three half hour periods in this season that produce the highest demand. Each Triad must be at least ten days apart, meaning they can’t happen on consecutive days, and this can be advantageous for customers if there is a particularly long lasting cold spell. The energy industry bases the Transmission Network Use of System (TNUoS) portion of customers’ half-hourly meter bills on the average demand during the three Triad periods. This is also where Triads get their name – “tri” refers to the three periods, while “AD” stands for average demand. These charges cover the use of the transmission system, administered by the National Grid ESO, for the whole year.

It’s during this period that customers will see the transmission charges applied to their usage, although the cost will be incrementally collected by suppliers over the year, based on estimated costs. For heavy users of energy, and others, this can turn out to be quite expensive.

Not surprisingly, many organisations will be looking for ways to avoid the full impact of these costs. For some, this will mean limiting their energy usage, or using on-site generation, during these times. Others may want to look at how they can incorporate this into a wider energy strategy, for instance, by signing up to our Virtual Power Plant which offers an automated Triad alert and dispatch service – this is a way of reducing the administrative burden associated with Triad periods as customers can simply allow us to manage it for them. Customers avoiding Triads can also limit other costs, such as distribution, as Triads tend to fall during the most expensive Distribution Use of System charges (DUoS) period.

Predicting Triads is not an exact science

Unfortunately, it’s not possible to predict these spikes in demand with 100% accuracy. That’s primarily because Triads are only determined retrospectively in March – the National Grid ESO crunches through the season’s data to work out which three periods registered the highest uptake. So businesses have to wait until later in the season to find out if they’ve got their forecasting right.

There are other reasons too: unusual weather patterns can distort results – we could see this happening this year if we get a repeat of the “Beast from the East” cold blast we experienced early in 2018 during the Triad season. In recent years, greater awareness of the impact of Triads on TNUoS charges has affected when they fall – more customers avoiding what they perceive to be busy periods has meant that other times have become busier as a result! This was particularly apparent during the 2015/16 season.

What can businesses do to lessen the impact of Triads?

Despite this, there are steps businesses can take to protect themselves from the costs associated with Triads.

  • Consider our Virtual Power Plant service: if you’re a larger organisation, or a heavy user of energy, our recently launched Virtual Power Plant (VPP) service can provide an automated Triad alert and dispatch service which can help relieve you of the administrative burden of doing your own forecasting. Not only can our VPP help you beat the extra costs associated with Triads, it can also make your energy work more flexibly for you by providing access to a wide range of other revenue streams and cost savings – whether this is from reducing demand or using on-site generation.


  • Sign up to a Triad alert service: SSE Business Energy, for instance, has its own service, which is free for customers. We sent out 20 alerts last year for potential Triad warnings – which draw on the knowledge and expertise of weather forecasters and energy specialists. While these can’t be guaranteed, as prices are set by the National Grid rather than energy companies directly, they do give you well-informed insights into when the busy periods could be. The National Grid also issues warnings when the system is likely to be under stress due to high demand and low generation.


  • Look at historical patterns: analysis of previous Triad periods can give you a reasonable indication of when these spikes are likely to happen. For instance, since 1990-91, all Triads have taken place between 4:30 and 6:30pm, with nearly nine in ten falling between 5pm and 5:30pm. Assess what you can do to limit your energy usage during these times. You can view the past few years’ data on the National Grid’s website here.


  • The last few seasons have also seen patterns emerging around the days of the week when Triads occur, as they’ve always fallen on Mondays and Thursdays. Triads have also taken place in December and January the last couple of years – which makes sense when you consider the colder temperatures at that time of year. However, it’s important to highlight the inherent uncertainty involved in making exact predictions – and when it comes to forecasting Triads, we’d always recommend taking advantage of existing services, such as our Triad alerts.


  • Treat every day like a Triad day: while you can’t predict when Triads might occur, getting into the habit of limiting your energy usage, for example, by turning off lights when no one’s in the room, or turning down your heating, means you’re less likely to be caught out by spikes. This could be an opportunity to review your organisation’s overall energy efficiency and there are tools available on our website to help you do this, including carrying out an energy audit and adopting this into company policy. We believe organisations of all shapes and sizes can benefit from taking these simple steps.

Predicting Triads is not an exact science, but those who do put an effective strategy in place, and stick to it, stand to reap the rewards. By doing this, these organisations are laying the foundations for an energy efficiency strategy that can benefit them all year round, not just during Triad season.

Following the above points is a starting point, but for more in-depth insight, visit our website. Existing customers can get in touch with their account manager.


Oliver McMillen

SSE Virtual Power Plant Director

Oliver is responsible for the development and delivery of Virtual Power Plant and Demand Side Response (DSR) related activity within SSE. As part of his role, Oliver works closely with external partners and colleagues to explore new products and services SSE could deliver using the VPP capability. He previously led the Corporate Affairs support – covering policy development, advocacy, and communications – for SSE’s Wholesale business.
View all posts by Oliver McMillen >

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