Transmission Network Use of System (TNUoS) Tariff Model

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


TNUoS Tariff Model

(DCLF ICRP Transport Model)

We publish the DC Load Flow Investment Cost Related Pricing (DCLF ICRP) Transport Model which allows users to undertake their own sensitivity analysis of generation and demand tariffs under different scenarios.

If you'd like a copy of the DCLF ICRP Transport Model, please contact us.

For more detailed information on the DCLF ICRP, please see Chapter 2 of The Statement of the Use of System Charging Methodology in Section 14 of the CUSC.


Transport model inputs

Electricity Ten Year Statement (ETYS) annual publications (Appendix G – Week 24 Demand data & Appendix F – Generator TEC register) are used as key inputs for the calculation of TNUoS tariffs.

Learn more about the TNUoS Charges


Charging Statements

The Charging Statements describe our charges and the methodologies behind them.


Triads Data

Triads are the three half-hour settlement periods with highest system demand. Learn more about Triads and access related data and guidance materials


Connection and Use of System Code (CUSC)

The CUSC is the contractual framework for connecting to and using the National Electricity Transmission System (NETS).

Additional help and support


Charging guidance

Access a range of guidance materials to help you understand how, when and what you’ll be charged.


TNUoS enquiries

Contact us directly to raise a query relating to TNUoS and our publications, or to provide feedback. Please note our usual contact number is currently unmanned due to COVID-19 homeworking.


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