On this page you will find all of the Triad data documents as well as links to guidance materials. 

What are Triads?

Triads are the three half-hour settlement periods with highest system demand. We use them to determine charges for demand customers with half-hour metering and payments to licence-exempt distributed generation.

Want to know more?

Take a look at our guidance on triads.

What are Triads?

Note: Indicative Triads are based on data received to date can be found on Elexon's Electricity Data Summary.

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Transmission Network Use of System (TNUoS)

Transmission Network Use of System (TNUoS) charges recover the cost of installing and maintaining the transmission system in England, Wales, Scotland and Offshore.