Your electricity bill is made up of many different elements and you
are charged using many different methodologies.
Your transmission costs are calculated using a methodology designed to influence peak times of electricity demand on the transmission network.
Although you are paying your Supplier, this charge is actually passed on from the Transmission System Operator – the National Grid. These charges recover the cost of installing and maintaining the National Transmission Network.
How is your cost calculated?
Your transmission costs are calculated through two methods, a £s/day rate based on your Authorised Supply Capacity and a smaller portion based on the previous Triad methodology.
Daily Rate
This regional £/day rate is banded based on your Authorised Supply Capacity (ASC). It will make up the majority of your transmission charges and provides another reason to review your Authorised Supply Capacity.
Triad Methodology
This aspect of your transmission costs for the year is calculated from your average demand during the three periods of highest demand on the UK electricity system between 1st November and the end of February. These three periods are termed Triads and must be separated by at least 10 days.
Your average demand during the three Triads is then multiplied by a regional rate (£/kW) to calculate your annual Transmission cost. This regional rate has dropped in recent years and for some regions, the rate will no longer exist.
Minimising your costs
It is now much harder to make significant savings by reducing your demand or switching to onsite generation during a Triad period due to this reduction in rate. If you are still charged based on the Triad methodology then many companies including Suppliers offer Triad warning services. These aim to predict Triad periods based on many factors including recent demand levels, historic patterns and relevant temperature/weather data.
Since 1991, all triad periods have been between the times of 16:30 and 18:30. Reducing demand consistently in this period during the winter months will save you money regardless of successful Triad prediction.
Analysing your transmission costs
Analysing your transmission cost exposure
How do I check my performance during the Triad season?
Check out our Actual Triad reports in the Static Cost area of Stark ID.
To analyse your transmission costs, you will need to provide additional information to Stark.