Every generation or storage device connected to the UK grid has to be notified to the local Distribution Network Operator. In the South West that is National Grid Electricity Distribution. There are two routes, and which one applies changes your timeline.
G98 — notify after the fact
For small installations — broadly up to 3.68 kW per phase — you can install first and notify within 28 days. Most modest domestic solar arrays fall here, and there is no waiting.
G99 — apply before you install
Anything above that threshold, including most solar plus battery combinations and all commercial arrays, requires approval before installation. The DNO assesses whether the local network can absorb the export and may impose an export limit.
- Standard G99 domestic decisions typically take a few weeks
- Larger commercial applications can take longer and may carry connection costs
- An export limitation device is a common and perfectly workable outcome
- We submit and manage the application as part of every quote — it is not an extra
If an installer asks you to handle your own DNO application, treat that as a warning sign about the rest of the job.
