P375 'Metering behind the Boundary Point': a game-changer for electricity asset co-location

What does P375 do?

P375 is a ground-breaking modification to the Balancing and Settlement Code (BSC) and was finally implemented on 30 June 2022.It allows on-site electricity assets sitting behind the 'grid boundary' (the point of connection between the site and the electricity distribution network) to use 'secondary' meters (aka 'asset meters' located at or near those assets) to record exactly how much electricity the assets are producing or consuming, and to use that data for the purpose of 'settlement'.Previously settlement had only been possible at the main meter at the grid boundary, meaning individual assets sitting behind that boundary ('behind the meter') could not be settled independently of one another (only on an aggregated, site-wide basis).

The BSC, managed by Elexon, contains the rules and governance arrangements for electricity balancing and settlement in Great Britain. Elexon compares how much electricity generators and suppliers say they will produce or consume with the actual volumes they produce/consume ('settlement') and makes sure everyone is paid accurately for any differences ('imbalance'). For further info see: What is the BSC? - Elexon BSC

Why is P375 important?

By allowing settlement at asset meters, P375 enables individual assets behind the meter to participate in the Balancing Mechanism (BM) and to provide balancing services to the electricity system operator (ESO, currently National Grid), thereby generating revenue.

The BM is the ESO's primary tool for balancing supply and demand on the GB electricity network. The ESO also procures balancing services to assist in that balancing exercise and to ensure the security and quality of electricity supply across the network. For more info see: Balancing Services | National Grid ESO

Thanks to P375, third party aggregators (aka 'Virtual Lead Parties' or VLPs) can now aggregate individual assets to participate in the BM and meter them separately from other assets on the same site, therefore avoiding the risk of imbalance. Previously VLPs had to bear the significant risk of incurring imbalance charges resulting from the 'mingling' of energy volumes from assets in the VLP's aggregated portfolio with those of other assets on the same site and the consequential inaccuracy of settlement data at the main boundary meter.

VLPs are independent aggregators who manage electricity generation and/or demand for a portfolio of assets on behalf of the asset-owners for the purposes of selling balancing services to the ESO

Assets sitting 'behind the meter' might include small-scale low carbon generation, battery storage, gas-fired CHP engines, demand-side response (DSR) and/or electric vehicle chargepoints.

DSR is the process by which energy customers turn up, turn down or shift their electricity demand in order to help the ESO balance supply and demand on the electricity system. DSR providers are paid for providing this service, in the same way as generation and storage assets are paid to provide balancing services.

What is required for P375?

To benefit from P375, asset-owners must use meters which comply with a newly-created code of practice (COP 11). COP 11 also allows for DC metering, which means on-board metering in EVs could, in theory, be used for balancing services. For further info see: New BSC Code of Practice (CoP11) sets standards for accuracy of Asset Metering Systems - Elexon BSC

Interested in learning more? Consider yourself an energy geek! Contact our own energy geeks here.


The content of this page is a summary of the law in force at the date of publication and is not exhaustive, nor does it contain definitive advice. Specialist legal advice should be sought in relation to any queries that may arise.

Get in touch

Contact us today

Whatever your legal needs, our wide ranging expertise is here to support you and your business, so let’s start your legal journey today and get you in touch with the right lawyer to get you started.


Get in touch

For general enquiries, please complete this form and we will direct your message to the most appropriate person.