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The Easy Guide To kVA Levels / Capacity Allowance

Under P272, businesses will find a new capacity charge on their bills, but what is it, and why is understanding what your capacity is so important for network providers? Here we answer some common questions.

What is an Authorised Service Capacity or ‘kVA level’?

Your Authorised Service Capacity (measured in kVA) is the level of ‘apparent power’ reserved from the network to guarantee the provision of a certain volume of power to your site. All sites with a half hourly meter have a kVA allowance – it is itemised on your bill as a capacity charge.

Your kVA level should be set according to twice the maximum amount of energy you use in a half hour period at your peak.

How should my site’s kVA level be calculated?

Your supplier will suggest a capacity / kVA level for your site, depending on their calculations. The level needs to be set just above your maximum demand, which is twice the highest consumption used in any half hour period recorded in the previous 12 months.

If it is set too high then you will end up paying a higher capacity charge than is needed.

Why does setting the right kVA level matter?

If your kVA level is too high, then you are essentially paying for more capacity than you actually need – you could be paying significantly more for your electricity per site. If you have multiple sites then the cost of having the wrong kVA level can quickly rack up.

How does this relate to P272?

Sites with non-half hourly meters have an inherent capacity charge built in to their electricity costs.
But under P272 many more non-half hourly sites will soon be settled on the half hourly market – and because of this they need to have a kVA (capacity) allowance set for them.

Suppliers are writing to sites affected by P272 to let them know that the kVA levels have been suggested for these sites. We would advise not to simply accept the level given but to interrogate it – otherwise you could end up paying for capacity that you don’t need!

How do I know that the right kVA level has been set for my site?

Ask your supplier to show you how they have calculated your kVA level. It should be set just above your maximum demand peak (if your power factor is approaching unity and you are not looking to increase demand on site). If your site is new to half hourly metering then your supplier may not have the consumption data available to work this out accurately. If you need advice on how to interrogate your kVA level or where it should be set, then contact us.

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