We are a separate company

On 1 April the Electricity System Operator became a legally separate company within the National Grid Group. Find out more about what this change means.

Charging policy and guidance

On this page you will find guidance materials, consultation documents, policy decisions, and the latest Triads data.

If you would like to receive regular updates on TNUoS and BSUoS, including invitations to our forums and training sessions, click here to subscribe to our e-newsletters.

Charging guidance documents and webinars

Click here to play the webinars which go over what we covered at our Charging and Settlements forums in October 2018.

1) TNUoS Tariffs and Forecasting [click here to watch] (length: 45 minutes)
2) TNUoS Charging and Billing [click here to watch] (length: 15 minutes)
3) BSUoS Reporting and Forecasting [click here to watch] (length: 15 minutes)
4) BSUoS Billing [click here to watch] (length: 20 minutes)

The following documents are designed to give you a better understanding of electricity generation charges and related topics. 

Charging methodology policy decisions

These are policy decisions documents relating to TNUoS charging methodology that are not codified within the CUSC.

Open letters, consultations and notices

These documents are open letters and informal consultations relating to TNUoS charges.

Triad data 2014-2018

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.

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