Guest Blog: npower’s Wayne Mitchell on Triad Season

Why inaction equals energy higher bills Apologies to those of you enjoying an almost balmy September, perhaps optimistic that above-average temperatures are here to stay. But according to long-range forecasts, […]

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By Geoff Curran

Why inaction equals energy higher bills
Apologies to those of you enjoying an almost balmy September, perhaps optimistic that above-average temperatures are here to stay. But according to long-range forecasts, after a mild start, the UK is due a cold winter this year, with below-seasonal temperatures and a strong likelihood of snow.

For those of us working in the energy sector, watching the weather is important, as colder temperatures usually equate to increased energy consumption.

But the winter also blows in the Triad season, the time when National Grid sets its annual network transmission charges, based on consumption during the three half-hourly periods of greatest demand between 1 November and 28 February.

Five-figure penalties
For large consumers, reducing consumption at these times can deliver huge savings, especially when these charges can be as much as £34,000 per megawatt, depending on your location.

Of course, the challenge is predicting when Triads will occur – because no-one knows until after the season’s over, when the analysts at National Grid sit down to pour over the data to work out when the three half-hours of peak demand occurred.

Triad forecasting: the good news
If you’re new to Triad avoidance, and even if you’re not, working out when a Triad is likely to occur isn’t easy. But let’s start with the good news:

  • Triads occur between 4.30pm and 6.30pm from November to February.
  • The main driver is when the domestic teatime period clashes with end-of-day industrial demand, so Triads nearly always occur on a weekday, with only two ever falling on a Sunday since the measurement began in 1972.
  • Historically, around 70% of Triads have occurred between 5pm and 5.30pm, with 25% between 4.30pm and 5pm.
  • December and January have been the most common months, with Tuesday the most popular day, followed by Monday and then Wednesday and Thursday on level pegging.

The first-ever Triad on a Friday occurred last year, which unfortunately caught everyone by surprise.

Now it gets more tricky

Of course, Triads are most likely to occur during a cold snap. But as each of the season’s three peak half hours must be separated by ten clear days, it can make prediction more difficult. Other factors that make forecasting complex include:

  • Unusual weather patterns becoming more common-place with, for example, winter temperatures way above – or below – seasonal norms.
  • The UK’s use of cross-border interconnectors to help balance supply and demand, although thanks to lobbying from our forecasting team, information relating to how and when these are being used is now being made available.

What’s more, as more large consumers become aware of the benefits of Triad avoidance – and therefore reduce demand during possible peaks – predicting when these peaks will occur becomes ever more challenging. This is because demand reduction on a larger scale creates a negative feedback loop – so potential peaks then flatten out.

Triad warning service
As a consumer, avoiding potential Triad periods can clearly be financially worthwhile. But rather than trying to figure out when these are for yourself, you can sign up to our Triad Warning Service (also available to non-npower customers). This provides day, day-ahead, week-ahead and also two-weeks-ahead warnings – delivered by email and/or text.

Our free-to-use online Triad Costs Calculator can also help you work out potential savings.

If you’re concerned about the impact to business production of reducing demand, we can also help you decide if on-site generation could provide a cost-effective solution. Or if you have existing generation assets, SmartSTOR can help you to manage demand during Triad periods. Both options can also provide a source of revenue during other times of system stress.

So even if a cold winter seems a long way ahead at the moment, at least you can take steps to be prepared for the financial implications to your energy bill.