Triads Data

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.

Transmission Network Use of System (TNUoS)