Why would the network operator cap my solar export?
Short answer
Where local cables already carry a lot of solar, the network operator can approve a bigger system only if export is limited, using a G100 export-limitation scheme. G99's small-installation routes cap export at 16 A or 32 A per phase. You can still generate and store more than you export.
Last checked 24 September 2026 · 1 source
In more detail
- SGI-2: aggregate <32 A/phase, export <=16 A/phase, DNO reply within 10 working days.
- SGI-3: aggregate <60 A/phase, export <=32 A/phase (waivable if aggregate <=32 A); DNO may study and reinforcement may be chargeable.
- Commissioning date 10 working days to 3 months after application.
The facts, dated
- 01G99 SGI-2 export limitation cap — 16 A per phase
standard · GB · checked 24 September 2026 · dcode.org.uk
- 02G99 SGI-3 export limitation cap — 32 A per phase
standard · GB · checked 24 September 2026 · dcode.org.uk
- 03DNO provides SGI-2 assessment result within — 10 working days
standard · GB · checked 24 September 2026 · dcode.org.uk
What we saw in the field
[QA review 2026-09-24] C1-4 AGREES (5 kW cap = DNO study outcome between SGI-2 16 A and SGI-3 32 A). I-7 AGREES. | Earlier notes: Agrees in principle: customer 1 wanted 7.5 kW export but the DNO capped it at 5 kW due to local solar saturation, bottlenecking battery charge/discharge to grid. 5 kW (~21.7 A) sits between the SGI-2 (16 A) and SGI-3 (32 A) caps, so it was likely a DNO-specific study outcome rather than a standard SGI cap. Installer claim that saturated areas get export restrictions: agrees.
Sources
- dcode.org.uk — dcode.org.uk/assets/250307ena-erec-g99-issue-2-(2025).pdf
Last checked: 24 September 2026