Licensed electricity distribution businesses, or Distribution Network Operators (DNOs) in Great Britain, are obliged under Condition 21 of their licences to maintain a Distribution Code detailing the technical parameters and considerations relating to connection to, and use of, their electrical networks.

DNOs

Electricity North West
www.enwl.co.uk

Northern Powergrid
www.northernpowergrid.com

Scottish and Southern Electricity Networks
www.ssepd.co.uk

SP Energy Networks
www.spenergynetworks.co.uk

UK Power Networks
www.ukpowernetworks.co.uk

Western Power Distribution
www.westernpower.co.uk

IDNOs

Energetics Limited
www.energetics-uk.com

ESP Utilities Group
www.espug.com

GTC (comprising both ETCL and IPNL licences)
www.gtc-uk.co.uk

UK Power Distribution Limited
www.ukpowerdistribution.co.uk

The GB Distribution Code

All DNOs currently operate the same version of the Code, and the Code is maintained by the Distribution Code Review Panel. All modifications to the Code have to be approved by Ofgem.

Issue 28: May 2017
This version of the Code has been revised to incorporate modifications to DOC5 and DOC7 to ensure compliance with the EU Network Code “Transmission System Operation Guidelines” (TSOG). The TSOG is expected to enter into force in summer 2017 and some parts of it are effective immediately. These changes are intended to ensure compliance with the TSOG on its entry into force.

In addition as part of its third Code Governance Review, Ofgem sought to introduce more flexibility to the GB Distribution Code (DCode) modifications process following a Significant Code Review (SCR). The proposed changes include three routes for progressing an SCR’s conclusions, with potential allowance to move between the processes. The Distribution Code and the DCRP’s Constitution and Rules have been aligned with the licence changes made by Ofgem to deliver these new processes.

Click here to download the current issue of the GB Distribution Code

For previous versions of the GB Distribution Code click here

User Guide
The guide gives a high level overview of the Distribution Code, and is aimed at anyone with an interest in the Distribution Code. It contains information about the regulatory structure in Great Britain and Europe and also provides a simple explanation of the various sections of the Distribution Code.

Click here to download the current version of the GB Distribution Code User Guide

Annex 1 and Annex 2 Documents

Some requirements of the Distribution Code are implemented through other industry documents. They are listed in Annex 1 of the Distribution Code, and are mostly Engineering Recommendations. These documents typically cover certain technical areas in detail, such as connection of generation, switchgear ratings and supply quality planning limits.

There are other industry documents which are not implemented via the Distribution Code, but do have a material impact on distribution network users. These are listed in Annex 2 of the Distribution Code.

Standards and other documents referenced in Annex 1 and Annex 2 of the Distribution Code are available for free and can be downloaded at the following link:

Click here for Annex 1 and Annex 2 documents

Standard Governance Procedure

DNOs or Users may bring proposals for modifications to Annex 1 Standards and Annex 2 Standards for consideration by the DCRP Panel. DNOs and Users bringing forward proposals for modifications to Annex 1 Standards and Annex 2 Standards shall set out in general terms the aims of their proposal and the likely impact, including costs.

Further information on how to submit a modification can be found here.

Useful Links

Association for Decentralised Energy (formerly the Combined Heat & Power Association)
www.theade.co.uk

Association of Meter Operators
www.meteroperators.org.uk

Department for Business, Energy & Industrial Strategy (formerly DECC)
www.gov.uk

Energy UK
www.energy-uk.org.uk

Major Energy Users’ Council
www.meuc.co.uk

Meter Operation Code of Practice Agreement (MOCOPA)
www.mocopa.org.uk

Microgeneration Certification Scheme
www.microgenerationcertification.org

National Grid
www.nationalgrid.com

National Grid
The Grid Code

Ofgem
www.ofgem.gov.uk

Renewable Energy Association
www.r-e-a.net

Renewable UK
www.renewableuk.com

Solar Trade Association
www.solar-trade.org.uk

Sustainable Energy Association (formerly Mircropower Council)
www.sustainableenergyassociation.com