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What are Triads?

Triads are the top three half-hourly peaks of national energy demand across the grid, separated by ten clear calendar days, over the most energy intensive period of the year: November to February. National Grid confirms these peaks after the season, at the end of March. Typically, triads occur when high business demand meets the domestic mid/late afternoon tea-time period, causing an overall spike in energy use.

How Triads impact your energy bill

To manage the huge demand on the network during the triad periods, the National Grid imposes a Transmissions Network Use of System (TNUoS) charge. This is used to finance the maintenance of the UK’s electricity grid to ensure future supply. Impacting customers with half-hourly meters, the charge is proportional to a business’ energy use over the triad periods (the three half hours of highest demand) and is linked to their location. If a business doesn’t consume electricity in the three Triad periods, they don’t pay HH (half-hourly) TNUoS charges for the entire financial year.

As standard, we include a charge for 85% of your maximum demand figure for TNUoS on our customer bills. After the final triads are announced, we issue the March invoices to show the triad periods and make any reconciliations.

The Met Office used Market Insight to help them manage their Triads and saved over £158,000.

The Triad challenge

To mitigate against Triad costs, companies and suppliers work hard to predict when they’ll be so they can turn down or off their energy usage during those periods. Due to the increasing use of Triad avoidance schemes as well as flexibility solutions, such as Demand Side Response and the growing use of renewables, they are getting harder to predict.

Getting ready for Triad Season

To manage the huge demand on the network during the triad periods, the National Grid imposes a charge: Transmission Network Use of System (TNUoS). Reduce your consumption during a triad and you'll make savings. However, increase your consumption and it could impact your budget.

Listen in as we explain how this works, what you'll see on your invoice, and what you can do to make savings.

Triads service

Triad status reports are issued Monday to Friday during the period November to February, excluding the Christmas holidays. They are issued either via SMS or email and are assigned a risk category:

  • Low Risk: A Triad is not predicted for the day
  • Medium Risk: Based on the information available there is some risk that a Triad may occur
  • High Risk: Based on the information available there is a significant likelihood that a Triad will occur

Market Insight

Our Market Insight service has been designed to help larger organisations make the right decisions. You’ll have access to quality data and expert analysis to help you control and manage Triads.

Our market experts use a range of complex factors to predict when Triads are most likely to occur, enabling you to significantly reduce your transmission costs.

  • Dedicated dashboard with Daily Triad Probability reports
  • Triad warning saving calculator
  • Historical data report from last season
  • Set your personal preferences for alerts
  • Access non-energy cost Monitor report

CCS Framework membership benefits

Crown Commercial Service is delivering value for the nation through outstanding commercial capability and quality customer service. EDF Energy is one of the UK's largest energy companies and the largest producer of low-carbon electricity. Together, we're working to help public sector organisations simplify their energy purchasing, understand the market and save time and money. Find out more