Japan Q-Headroom Map

Reactive-power headroom at every substation for a standard 50 MW BESS at 19% capacity factor. Green = ample headroom, red = at limit, purple = reactive-constrained (weak node), grey = insufficient local grid to analyse.

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Q-headroom values depend on your actual project MW and dispatch. The map is a screening tool, not a substitute for a formal interconnection study.

Q-headroom (MVAr)

≥ 20 MVAr — ample

10–20 MVAr — moderate

3–10 MVAr — tight

< 3 MVAr — at limit

Reactive-constrained (weak node)

Low confidence (screening estimate)

Not analysable / islanded

Screening tool only — not utility-confirmed. Q-headroom values computed by Rotormaps Katana using the publicly-available substation and transmission-line database. A converged result does not guarantee formal interconnection approval. Contact Sunpulse for a full site-specific analysis.

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