Triads. How energy storage can help businesses with charge avoidance.

Business end-users with half-hourly metering are charged for using the electricity network at certain peak times of the year through the Transmission Network Use of System (TNUoS) charge.

This demand charge can be significant and add thousands to your electricity bill depending on your demand from the grid during what are referred to as Triad periods.    

Let’s explore how battery energy storage can potentially avoid these charges and significantly lower your electricity bill.

What is a Triad?

National Grid says “The Triad refers to the three half-hour settlement periods with highest system demand between November and February, separated by at least ten clear days. National Grid uses the Triad to determine TNUoS charges for customers with half-hour metering.”

These three Triad periods are not known in advance, not even by National Grid.  Instead, they are calculated after the winter period November to February and then released by National Grid in March each year.  

The last set of Triads, year 2016/17, were 5th December 2016 (17:00 to 17:30), 5th January 2017 (17:00 to 17:30) and 23rd January 2017 (17:00 to 17:30).

How can battery energy storage help? 

There is one simple fact you need to be aware of.  If you don’t consume electricity in the three Triad half-hours, you don’t pay TNUoS charges for the entire financial year.  Yes, that is right - not a penny.

So, to avoid the TNUoS charge completely you need two things.

  1. An accurate forecast of when the Triads will be.
  2. A strategy to avoid using electricity from the grid during the Triad periods.


As the Triads are not known in advance, National Grid does not forecast them. However, National Grid does issue notices of insufficient system margin (NISM) when the system is likely to be under stress due to high demand and low generation (the perfect storm for a Triad).  However, your electricity supplier or energy broker is likely to provide a forecasting service to notify you when there is likely to be a Triad period. 

Whoever you use for forecasting, they will alert you to a potential Triad as much as 20+ times during the November to February period.

Avoiding using the grid.

So, now you know of likely Triads through your forecasting service, you need to have a strategy for avoiding the grid for power during these 20 or so alerts.  You could simply shut down your entire operation.  This is not appealing to most businesses as you will lose revenue from the loss of production or loss of service.  You may also incur reboot costs after the alert is over, especially in manufacturing.  Furthermore, you may affect your relationship with your customers and face fines for missing deadlines.

There is a better way.  Battery energy storage can help you be prepared.  Assuming you have the right size system for your operation you will be able to use stored power to run your entire operation for as long as two hours, ensuring you avoid using the grid during the half-hour Triad alert.  

Now, at this point, you may be thinking that you could use a generator.  If you have back-up power, such as a diesel generator, then yes you could opt for this method.  However, with emissions legislation getting tighter and the fact that generators can be costly to maintain, batteries offer a cleaner modern solution to back-up power.  Furthermore, the business case for battery energy storage is not based just on this charge avoidance.  Batteries offer several services including demand side response (DSR), peak shaving and optimising onsite renewables in addition to charge avoidance and a more reliable back-up power system (than old dirty generators).  Enabling you to solve the energy trilemma i.e. price, carbon and security.

If you would like to discuss charge avoidance or the many services offered by today’s battery energy storage systems, speak to Rock Clean Energy for an informal chat.

Finally, did you know that you may be able to get a free battery, fully installed and fully maintained with our Battery Energy Storage as a Service scheme (BESaaS).  Yes, FREE.  We can supply, install and maintain a battery on your site and we can share the commercial benefits, or you can buy a battery and enjoy all the savings and revenue generated.


© Written by Shawn Coles, Energise Marketing 93



Copyright © Rock Clean Energy 2017.