Understanding Triad Charges

What Are Triad Charges?

All HH settled meters within the UK pay a levy set by the National Grid based on each meter’s usage during the highest three half-hour periods of demand on the transmission networks.  The charges are calculated on your average maximum demand across the three periods, hence the name Triad charges.

Triad charges fall under the category of TNUoS (Transmission Network Use of System) charges, which are determined between 1 November and the end of February. Historically, they occur between 4pm and 7pm Monday to Friday, although the actual Triad periods used may not be the exact three highest periods of demand because each period must by at least 10 days apart from the others.


Triad charges have increased by 80% over the past five years.


My supplier doesn't charge me for Triad on my invoice, therefore I don't pay.


Triad charges are expected to increase up to 40% by 2020.


I can't do anything to reduce these charges; everyone has to pay them.

Why Do I Pay Triad Charges?

Triad charges are invested back into the transmission network, for maintenance and to ensure we have a modern transmission network. The charge is also used to ensure that our networks are capable of distributing the power required during peak times.

How Much Are My Triad Charges?

In some cases Triad charges can make up as much as 16% of your invoices. This means that, for a £1.6m annual energy spend, three half hour periods would have cost you around £100,000!

“But I didn’t use £100,000 worth of electricity in 90 minutes, did I?” you may ask yourself. You don’t have to. An energy spend of as little as £315—just over 1,000 kWh—in each of the half-hourly periods could have left you with a Triad charge that high.

If you’re a national company these charges could differ greatly depending on where you are based. For example if you have sites in Scotland and London, your charges in London are almost double those in Scotland.

Can I Reduce My Triad Charges?

One word answer here: YES!

Start by looking at the three main drivers which have a bearing on your Triad charges.

How You Buy It – Make sure you have full control of the type of contract you or your procurement agent is purchasing. You may not see a charge on your invoice, but I can assure you it’s there. Some suppliers will aggregate up charges to a “simplified” single rate. That means the supplier has estimated your usage and probably added a small percentage to cover themselves.

How Much You Use –Take control of your invoices, monitor your usage and understand where you are using your energy. Make sure you understand if energy use at your buildings is comparable to other similar buildings. If possible, use your data as a benchmark to ensure best use at that building.

When You Use It – Reducing your Triad charges is as simple as reducing your load during those three half-hourly periods. To make those reductions, it’s essential to have easily accessible real-time data showing you exactly what you are using at least every half hour. Good load management will help you shift energy usage to other periods or even switch to onsite generation if this is available.

Learn more about the three drivers of your Triad charges, and how you can better manage all three.
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Authored By Wayne Davies

For the past 12 years, Wayne has managed the delivery of Enel X's services to multinational, blue chip companies.

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