Winter 17/18 TRIAD dates
The results of the 17/18 TRIAD season were today confirmed by National Grid:
1. Monday 11th December ’17 – SP35
2. Monday 5th February ’18 – SP36
3. Monday 26th February ’18 – SP37
Nationwide Utilities successfully notified clients of ‘high chance of TRIAD’ (our strongest warning) for each of the three TRIAD periods.
TRIAD refers to the three half-hour settlement periods with highest system demand between November and February, separated by at least ten clear days. The TNUoS charge was introduced by National Grid to customers with half hourly metering to maintain supply and reduce peak demand during the winter months when the grid system is likely to be under increased stress.
These three periods are only confirmed by National Grid retrospectively once settlement data has been reviewed.
For the first time, two events occurred in February owed mostly to the cold spells at the start and end of the month. Traditionally, TRIAD events are most common on Mondays and the trend continued this season with each event occurring at the beginning of the week.
Predicting the time of TRIAD is becoming an ever more challenging task. This year, perhaps due to the uptake in demand side response (DSR), peak demand was suppressed initially before surging in a subsequent settlement period. DSR results in approximately 2GW of demand being removed from the transmission system mainly due to reducing load and onsite generation.