DC0079 / Accelerated Loss-of-Mains Change Programme (ALoMCP)
Recent updates to the Distribution Code mean that non-domestic renewable generators need to make changes to how they are connected to the grid.
This applies to any wind, solar PV or other form of generation that was installed before February 2018. Some 50,000 sites across the UK are affected.
The changes can usually be made at no cost to the generator, although that funding window will close in August this year and earlier applications are more likely to be successful.
Who does this apply to?
Compliance is required by any business that has a wind turbine, solar PV or other renewable generation that was installed before February 2018.
What changes are required, and why?
These installations were connected to the grid using G59 relays, which monitor voltage and frequency and disconnect the generator in the event of a grid disturbance. The G59 relays either need to have their settings changed or be replaced, depending on the type of relay that was used.
Rate of Change of Frequency (RoCoF) relays can be adjusted to meet the new G99 rules. Vector Shift (VS) relays will need to be replaced with RoCoF relays set to meet the updated Distribution Code.
Under the old G59 rules the settings were very sensitive, which tended to trigger disconnection within a few milliseconds in response to very slight disturbances on the grid. As the capacity of renewable generation has grown, its impact on the grid has increased to the point where spurious tripping by over-sensitive relays can threaten the stability of the grid.
The new G99 rules create a smarter system that will prevent disconnection due to minor faults, reducing the threat of large amounts of generating capacity disconnecting simultaneously.
What will it cost?
If they act promptly, generators should be able to comply with the new Distribution Code at no cost.
The ALoMC Programme was set up to incentivise early compliance. Funded by the National Grid ESO via levies on Balancing Services Use of System (BSUoS) customers, the costs are ultimately paid by consumers through their bills.
The Programme provides for the payments shown in the table below.
What are the timings?
Time is short.
The ALoMCP is open for a limited period, and the programme documentation states that: “the earlier an application is submitted, the higher the likelihood that application will be accepted”.
The final window for applications closes on 11 August 2020.
After the final window closes, owners of generation have until 31 August 2022 to comply voluntarily with the new Distribution Code, at their own cost. After that they are likely to be subject to an enforcement programme.
How can CleanEarth help?
We can help with each stage of the compliance process:
• identify the relays and their settings
• register the system on the ENA portal
• submit the application for funding
• make the necessary relay replacement or settings changes
• test the new settings and submit test report
• handle the paperwork
What should I do now?
Fill in the form below and we’ll get back to you to explain exactly what’s involved.
Alternatively, drop us an email at alomcp@cleanearthenergy.com or call 0800 975 5635.
We operate right across the UK, having installed over 500 wind and solar PV systems from Cornwall to the north of Scotland, so we have plenty of experience in the technical aspects of grid connections.
If you’d rather find someone else to do the work, the Energy Networks Association (ENA) has published a directory of contractors (you’ll find us at the bottom of page 7).
Useful links
If you’d like to know more about the background or the technical ramifications of ALoMCP, check out the links below.
ENA description of the programme.
Slideshow on the background and technical reasons behind the programme.