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Loss of Mains Change Programme

ALoMCP - Coronavirus Pandemic Response (updated April 2020)

Find out more about SP Energy Networks' role in National Grid ESO's accelerated Loss of Mains Programme, developed to support the implementation of changes to protection settings for generators.

Alongside other Distribution Network Operators (DNOs) and Independent Distribution Network Operators (IDNOs), we are joining forces with National Grid ESO on their 'Loss of Mains (LoM) Change Programme' - an initiative to help owners of generation assets make the necessary changes to ensure compliance with new settings introduced under the Distribution Code.

In the past, loss of mains protection would have seen generating assets being disconnected when necessary to stop any damage when problems occurred on the electricity distribution network. That would often have resulted in the costs of trying to stop any disruptions being paid for by the consumer and electricity industry, e.g. when renewable generation was running.

Required changes have been identified under the LoM programme to deliver better efficiencies in the operation of the distribution network in this way, allowing low carbon assets to operate at lower costs.

The LoM programme requirements specify that as well as these new requirements being applicable to new generation connecting to the network, they must also be applied retrospectively to all existing generation with loss of mains protection.

So as a generator, what do I need to know?

It is now a requirement of the Distribution Code – which all generators must adhere to – that all owners of generation installed prior to February 2018, and that currently comply with EREC G59, now need to comply with new settings required for the interface protection. This means owners will need to make changes to their protection settings, and have until 31 August 2022 to do so. Those who have not made these changes by the specified date may then be subject to an enforcement programme.

Support will be available to make these changes, including the opportunity to apply for a financial contribution to support the necessary work required (subject to availability and specific criteria), and a new portal is now available to allow such applications to be submitted.

Please visit the Energy Networks Association website for further information and to access the portal.

Recognised Contractors

Please find a list of recognised contractors here: 

Applications are welcome from all contractors / consultants who wish to obtain recognised status for the duration of the Accelerated Loss of Mains Change programme and are able to prove they have met the application criteria.

It is expected that there will be a large number of generation sites making changes to their Loss of Mains (LoM) protection as part of the Accelerated Loss of Mains Change Programme (ALoMCP). The work required on generation sites as part of this programme, e.g. replacing a protection relay, typically requires DNO witness testing. To facilitate the high volumes expected in this programme, industry has agreed to allow generation sites to make the required LoM changes under this programme through “self-certification”.

What is Self-Certification?

Self-certification enables generation sites to carry out the required work under this programme without the requirement for DNO witness testing. Generation sites can self-certify if the required works on site are solely a settings change to an existing protection device. If the required works on site involves a protection device replacement or LoM function deactivation, generation sites can self-certify if the work is undertaken by a recognised contractor.

How to become a recognised contractor

A contractor will be given “Recognised Contractor” status when SP Energy Networks deems them to be competent to successfully make the changes to a generator owner's loss of mains protection. The status shall be given automatically once a contractor has submitted three test certificates which have been witnessed and signed by a current SP Energy Networks engineer.

These should be submitted to using the application form below, with “Recognised Contractor Application” as the subject line.

It is important to note that “Recognised Contractor” status shall only be granted to an individual contractor. This means if several contractors from a company carry out witness testing, they must individually fulfil the above criteria.

Sample site visits

SP Energy Networks, potentially accompanied by a representative from National Grid ESO, may wish to carry out a sample site visit following any changes made to loss of mains protection.

The time and date of any sample site visits will be agreed with SP Energy Networks, the generator owner and a National Grid ESO representative (if required) beforehand.

If an individual is found during the sample site visits to have incorrectly completed the changes to loss of mains protection, their status as a “Recognised Contractor” shall be removed and they will be contacted with details of future steps required.

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