Ofgem's Balancing and Settlement Code Modification Proposal 272

What is P272?

Man installing meter - P272 - E.ONP272 is an Ofgem change to the Balancing and Settlement Code aimed at making settlement and billing more accurate through Half Hourly (HH) readings. For most customers the changes took effect on or before the deadline date on 1st April 2017. The change affected meters with profile classes 05, 06, 07, and 08.

What was the rationale for P272?

The modification proposed that the industry should use energy data for ‘settlement’ to improve accuracy. It also helps distributors better understand electricity use, so they can make sure the networks are maintained properly.

Settlement is how suppliers match, and pay for, the energy consumed by customers, to the energy purchased on their behalf.

For non-half hourly sites, consumption is ‘profiled’ across the industry, based on what a typical customer in a relevant Profile Class uses. It means suppliers must obtain meter readings before they can ‘settle’ based on actual consumption.

For half-hourly sites, the meters record the consumption reading every half hour, rather than waiting for meter readings. This means suppliers settle their consumption based on actual usage.


What are the benefits to my business?

Half hourly meter reading and charging provides a better understanding of your business electricity use, and allows us to improve the way we price and bill to more accurately reflect how you use electricity.

The HH data can also help your business planning in terms of any energy efficiency measures you may want to implement.

What about billing?

Depending on your contract type, Distribution Network Operator (DNO) capacity charges may be applied and itemised giving you more visibility of bill breakdown.  These charges cover Authorised Supply Capacity; and Excess Capacity charge. More details about these charges are explained in the FAQs below;

What is Authorised Supply Capacity (ASC)?

ASC is sometimes referred to in the industry as Maximum Import Capacity (MIC) and it is the limit of electrical load (demand) that the Distribution Network Operator (DNO) makes available to Half Hourly Metered sites. This is measured in kilovolt Ampere (kVA).

What is DNO?

DNO stands for Distribution Network Operator. DNOs look after the network of towers and cables that transport electricity to homes and businesses. Your DNO also ensures the safety of your connection to the electricity network.

How do I find out who my DNO is?

There are 14 licensed DNOs in Britain and each is responsible for a regional distribution services area as shown below.  

 Area ID


 Supply Network

 Contact Numbers


East England

UK Power Networks 

0800 029 4280


East Midlands

Western Power Distribution 

0800 096 3080



UK Power Networks 

0800 029 4280


North Wales, Merseyside and Cheshire

SP Energy Networks 

0330 10 10 444



Western Power Distribution 

0800 096 3080


North East England

Northern Powergrid

0800 011 3332


North West England

Electricity North West 

0800 048 1820 


North Scotland

SSE Power Distribution

0800 048 3516


South Scotland

SP Energy Networks

0330 10 10 444


South East England

UK Power Networks

0800 029 4280


Southern England

SSE Power Distribution

0800 048 3516


South Wales

Western Power Distribution

0800 096 3080


South West England

Western Power Distribution

0800 096 3080



Northern Powergrid 

 0800 011 3332



Independent Power Networks Ltd

01359 243311



ESP Electricity Limited 

01372 227560



Energetics Electricity Ltd 

01698 404949



The Electricity Network Company Ltd (GTC) 

01359 243311



UK Power Networks (IDNO) Limited 

0845 601 4516

Why is ASC important?

It places an upper limit on the total electricity load you can use without incurring excess charges. You are charged for this upper limit whether you have reached your ASC or not.

This means:

If the ASC is set too high, you may be paying for more capacity than you actually require.

If the ASC is set too low, you may incur an 'Excess Capacity' charge for exceeding your ASC.

Can I change my ASC?

If you think your ASC is too high or too low, you can request to change this through your DNO.  

I have just moved to a new site. How does this impact me?

If you have moved into a new site where the ASC was set by the previous occupant, you could be paying for ASC that is not appropriate for your business needs. The previous occupants Supply Capacity will have been carried over to your current Supply Agreement, even if there has been a change of Supplier. Contact your DNO for any queries regarding your ASC.

What is Excess Capacity charge?

If your maximum demand (the peak demand recorded on your meter in a billing period) exceeds your ASC, additional charges will be incurred. These are shown as Excess Capacity Charges and are measured in kVA. These charges are billed for every day of the billing period at the maximum demand recorded.

If your ASC changes during your billing period, the maximum capacity is calculated in two parts; before and after the ASC change. In this scenario, you will see two separate lines on your bill for both ASC and excess capacity, but charged excess only for the billing period where the ASC was breached.

Will Excess Capacity ever be estimated?

From time to time the data collector may not be able to communicate with your meter resulting in us being provided with estimated consumption and maximum demand levels. If the estimated consumption is above the ASC, then this will result in estimated Excess charge. If this happens your bill will clearly state when consumption has been estimated and this will be corrected when we have received accurate reads.