Triads came early in 2019 and our warning service predicted them

Triads are the three half-hour periods of highest demand for electricity in Great Britain. They fall during winter, and must be at least 10 days apart. National Grid bases Transmission Network Use of System (TNUoS) charges for the whole year on each half-hourly metered consumer’s average consumption during Triads. This means that using power during a Triad can end up being costly for heavy users.

That’s why we offer our customers a Triad warning service, to help them reduce their demand during these times. Avoiding Triads can limit other costs, too – they tend to fall during the most expensive Distribution Use of System (DUoS) charging period, for example.

I’m pleased to say that our forecasts picked up 100% of these peaks and we warned registered customers before each one. However, even with the expertise of energy demand specialists and weather forecasters, it’s challenging to predict Triads accurately, and becoming more so.

Although Triad season runs from the start of November to the end of February, in 2019-2020 all three Triads occurred before Christmas, for the first time ever since the system began in 1990.

There are a few different factors which help to explain this. To start with, power demand peaks were lower than last year, due to an exceptionally mild winter.

However, Triads are not simply about when the weather is coldest. Another factor that’s worth calling out is that more businesses are integrating Demand Side Response and embedded generation into their energy management strategy, allowing them to increase or reduce their demand. This suppresses demand overall and flattens peaks throughout Triad season.

Triad warnings can even alter how likely a day is to be a Triad. If lots of consumers react to energy industry alerts about the likelihood of a Triad occurring it can significantly alter system demand – meaning that what was thought to be a higher risk day can turn out to have lower peaks than those days which were seen at the time to be lower risk.

The following graph from National Grid shows how power demand peaked during winter 2019-20:

Triad-based charges are set to be replaced by fixed charges from April 2022, following Ofgem’s Targeted Charging Review. If the new TNUoS charges go ahead as planned they will be per day, per site, depending on each consumer’s region, connection voltage and maximum import capacity or annual consumption.

For Triad season 2020-21, there are still opportunities to mitigate the risk of hefty costs. I suggest the following:

Reduce your energy demand

Limit your electricity usage, or use on-site generation, during these times. In addition, look at lowering your consumption in general. Our online energy management platform, SSE Clarity, can help you work out where you could implement energy efficiency measures, and it’s free for our customers.

Review your energy strategy

For those of you with the ability to be flexible in how you use your electricity, our Demand side response - Virtual power plant offers an automated Triad alert and dispatch service, with the admin and forecasting managed for you. As part of a wider energy strategy, VPP can also help you access a range of revenue streams and cost savings.

Register for Triad warnings

And of course, sign up for our Triad warning service. It’s simple – we’ll email you to let you know when peak power demand is likely to occur. While we cannot guarantee to give exact timings, we’ll do our best to provide well-informed alerts – and as I mentioned our forecasts were 100% accurate this last winter.

To talk through Triads and solutions for your energy needs, contact us – existing customers can get in touch with their account manager.