Each year, the National Grid are paid a Transmission Network Use of System (TNUoS) fee to finance the cost of maintaining the UK’s electricity grid.

Triads are used to determine TNUoS charges for business customers with half-hourly metering. However, with prior warning, you can reduce this charge – which often runs to tens of thousands of pounds – by reducing consumption when you know a Triad is going to occur.


What are Triads?

Triads are the three half-hour settlement periods with highest system demand between November and February. The settlement periods typically occur during cold weather, when industrial demand coincides with the domestic tea-time period 4pm to 6pm.

Triad Alert Notification Service:

We work closely with our suppliers to provide our clients with a free Triad Alert Service, giving the opportunity to reduce consumption during the forecasted settlement periods.

Types of alerts you will receive:

Day ahead triad alert – when demand is forecast to peak to pose a Triad Risk. Same day triad alert – on the rare occasion forecast demand shifts to pose a Triad.

By reducing your consumption on Triad days, you can reduce your TNUoS charges for the whole year. Our Triad Alert Service tells you when to reduce your demand.



If you are an Inspired Energy client and would like to benefit from our Triad Alert Notification Service, simply fill in the form below.

Triad Warning Sign-up

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