Value chain · CLM-0780
In plain terms
The UK rules for connecting power stations set a hard limit on how much generation one fault may disconnect at once: 1800 MW for a fault on the station's own connection, and nothing at all for a fault on a single transmission line.
The claim as recorded
The Great Britain NETS Security and Quality of Supply Standard fixes two loss-of-infeed thresholds numerically, a Normal Infeed Loss Risk of 1320 MW and an Infrequent Infeed Loss Risk of 1800 MW, both effective from 1 April 2014, and clause 2.6 requires of onshore generation connections that a fault outage of any single transmission circuit cause no loss of power infeed at all, and that a fault outage of any single generation circuit or single section of busbar or mesh corner cause a loss of power infeed not exceeding the Infrequent Infeed Loss Risk; both clauses use "shall", not "should".
Scope and limits
This states the standard's requirement. It does not establish that any SBSP design has been assessed against it, and it says nothing about jurisdictions outside Great Britain. The 1000 MW and 1320 MW pre-2014 values are retained in the glossary text and must not be quoted as current.
What it assumes
That a ground rectenna exporting to the GB transmission system is a "generation connection" for the purposes of clause 2.6, with no SBSP-specific derogation. Nothing in the standard suggests an exemption exists, but none has been sought either.
Where it comes from
Glossary, verbatim: "Normal Infeed Loss Risk Until 31st March 2014, this is a loss of power infeed risk of 1000MW. From April 1st 2014, this is a loss of power infeed risk of 1320MW." Glossary, verbatim: "Infrequent Infeed Loss Risk Until 31st March 2014, this is a loss of power infeed risk of 1320MW. From April 1st 2014, this is a loss of power infeed risk of 1800MW." Clause 2.6 preamble, verbatim: "Generation connections shall be planned such that, starting with an intact system, the consequences of secured events on the onshore transmission system shall be as follows:". Clause 2.6.1, verbatim: "following a fault outage of any single transmission circuit, no loss of power infeed shall occur;". Clause 2.6.3, verbatim: "following a fault outage of any single generation circuit or single section of busbar or mesh corner, the loss of power infeed shall not exceed the infrequent infeed loss risk;". Clause 2.5.1 defines the quantity as "the sum of the registered capacities of the generating units disconnected from the system by a secured event".
Basis: the standard as in force at version 2.12, 29 May 2026; onshore transmission system clauses
Related records
- Answers question
- QST-012 not published in this release
Cite this
energyaperture.com/c/clm-0780
CLM-0780, Energy Aperture, as of 2026-05-29.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-238
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