Value chain · CLM-1107
In plain terms
The actual Grid Code figure is not a flat 0.95 power factor at all voltages: the plant must push reactive power out when the grid voltage sags towards 0.9 and absorb it when the voltage rises towards 1.1, and full capability both ways is only demanded in a narrow band around nominal. At part load the requirement is a third of rated power either way, easing on the absorbing side below half load.
The claim as recorded
For an Onshore Type C or Type D Power Park Module connecting above 33 kV, the Grid Code's reactive capability at Maximum Capacity is Figure ECC.6.3.2.4(a), a tilted band of Grid Entry Point voltage against power factor: at unity power factor the module must operate from 0.95 to 1.05 pu; at 0.95 lag (exporting MVAr) from about 0.875 to 0.9 pu up to about 1.03 pu; at 0.95 lead (absorbing) from about 0.97 pu up to 1.05 pu, the envelope reaching about 1.1 pu just inside full lead. Below Maximum Capacity, Figure ECC.6.3.2.4(c) requires Q/Pmax of -0.33 to +0.33 from 0.2 to 1.0 pu active power, the absorbing limit reducing linearly from -0.33 at 0.5 pu to -0.12 at 0.2 pu unless The Company specifies otherwise, with a +/-0.05 band below 0.2 pu. The 0.33 is tan(acos 0.95). A module connecting to a Non Embedded Customer's system "may be required to meet additional reactive compensation requirements at the point of connection" for System reasons.
Evidence behind this: T1-the code text and its figures read directly, replacing the guidance-derived CLM-0783 for the Type D case.
Scope and limits
The vertex voltages of Figure (a) are read from a schematic figure with no printed values at the vertices: the bottom vertex is drawn between the 0.9 and 0.875 gridlines and the top just above 1.1, both with grey dashed extensions to 0.875 and 1.1, so "about" is deliberate and a reader needing the exact vertex should take the figure itself. Figure (b) (at or below 33 kV) is not the SBSP case and is not stated here. Nothing here bears on whether a rectenna converter fleet can meet the envelope; CLM-0784's MVAr arithmetic used the flat 0.95 reading, and the figure asks for that 0.95 lag capability down to about 0.9 pu, where the same MVAr means about 11 per cent more current, a point for CLM-0784's successor rather than a correction here.
What it assumes
No assumptions are recorded against this claim.
Where it comes from
PDF p.223, normalised: "shall be capable of satisfying the Reactive Power capability requirements at the Grid Entry Point or User System Entry Point" ... "as defined in Figure ECC.6.3.2.4(a) when operating at Maximum Capacity"; "may be required to meet additional reactive compensation requirements at the point of connection between the System and the Non Embedded Customer or private network where this is required for System reasons". Figure (a) read from crop p0224-fig-ecc-6-3-2-4a-reactive-envelope.png (the figure has no text layer; its labels are render readings): gridlines 1.1, 1.05, 1.0, 0.95, 0.9, 0.875; x axis -0.95 "Consumption (lead)", 1, 0.95 "Production (lag)"; bracket "0.225". Figure (c) from crop p0225-fig-ecc-6-3-2-4c-reactive-below-max.png (no text layer; labels are render readings): ticks -0.33, -0.12, -0.05, 0, 0.05, 0.33 on "Q/Pmax"; 0.2, 0.5, 1.0 on "Power (p.u)". p.225, normalised: "With all Plant in service, the Reactive Power limits will reduce linearly below 50% Active Power output as shown in Figure ECC.6.3.2.4(c) unless the requirement to maintain the Reactive Power limits defined at Maximum Capacity" ... "under absorbing Reactive Power conditions down to 20% Active Power output has been specified by The Company". Arithmetic: tan(acos 0.95) = 0.3287; 1.1 - 0.875 = 0.225.
Basis: per-unit voltage at the Grid Entry Point against power factor at Maximum Capacity; Q/Pmax against per-unit power below it
Related records
- Answers question
- QST-012 not published in this release
Cite this
energyaperture.com/c/clm-1107
CLM-1107, Energy Aperture, as of 2026-06.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-452
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