National Grid has confirmed the three winter evening peak periods upon which it bases annual charges for use of the transmission system.
Called Triad periods, these are defined as the three half hours of highest peak demand over winter, at least 10 days apart. If businesses cut their energy use or switch to on-site generation during these periods, they can avoid a significant portion of their network charges for the year. Embedded generators can, for now, also make significant revenue from Triads.
However, those three Triad peaks are only confirmed by National Grid retrospectively.
As such, many suppliers and third party intermediaries (TPIs) send out warnings to companies over winter when capacity margins look tight stating that there is a risk of Triad occurring.
With National Grid today confirming that last winter’s Triad periods fell at 5-5.30pm on Monday 5 December, Thursday 5 January and Monday 23 January, businesses will now find out how well their Triad alerts provider performed.
No provider wants to miss a Triad, or risk their credibility. Equally, sending out too many Triad alerts risks annoying customers, because they will then ramp down equipment or ramp up onsite generation, often generators, at a loss.
The consensus is that accurately predicting Triad periods in around 20-25 calls over winter is a good balance.
Most providers also now grade their alerts, outlining how likely a Triad occurring might be.
Utilitywise was the first TPI to react to National Grid’s Triad confirmation. The firm said it had accurately forecast all three Triads in 17 calls in total, ten of which were ‘red’ alerts.
Whether any provider managed to accurately forecast the Triad periods in fewer calls remains to be seen. But failing to correctly call them will prove painful: for some businesses, the costs of missing a Triad period are such that they are moving to cut consumption altogether during the 4-7pm winter peak.
Download the Triad data here.