G98 vs G99: DNO Notifications for Solar and Batteries
DNO connection requirements depend on the generation equipment, export arrangement and installation circumstances; confirm the process before commissioning.
G98 and G99 are commonly discussed routes for connecting generation equipment to a distribution network. The applicable process must be confirmed from the equipment, connection arrangement and current network guidance rather than guessed from system size alone.
This is practical guidance for competent electricians. Assess the actual installation, follow the current edition of BS 7671 and manufacturer instructions, and stop where the work cannot be completed safely.
Key takeaways
- Agree the scope and make the installation safe before starting work.
- Use a controlled sequence rather than relying on a single reading or visual assumption.
- Record the actual result, limitation or action taken while it is still traceable.
- Check the result against the design, protective measures and equipment instructions.
- Issue the appropriate certificate or report when the work is complete.
Scope the work first
G98 and G99 are commonly discussed routes for connecting generation equipment to a distribution network. The applicable process must be confirmed from the equipment, connection arrangement and current network guidance rather than guessed from system size alone.
Method
Gather inverter, battery, export-control and supply details early; contact or use the relevant DNO process before work where required. Keep approvals, commissioning settings and serial-number evidence with the project.
Doing this on a job? Solar PV SSEG Commissioning Confirmation (G98/G99) — part of TradePlanr. Free to start, no card needed.
Checks and common pitfalls
Do not commission an export arrangement based on a verbal assumption or rely on an outdated DNO form. Check the current process for the local network operator and ensure inverter settings match the approved design.
Record and hand over
Give the client the notification or approval evidence, commissioning record, operating instructions and electrical certificate. Retain the same records so later battery or inverter changes can be assessed safely.
Keep the evidence with the job
Record readings, limitations and remedial actions as you work. A clear certificate or report protects the client and makes the next visit easier to manage.
From guidance to action
Frequently asked questions
Is G98 always used for a small solar installation?
Not necessarily. The correct route depends on the connection and current network rules. Confirm it with the relevant DNO guidance before work is committed.
Can I rely on a standard rule of thumb?
No. The installation method, supply characteristics, equipment instructions and the current requirements all affect the correct decision. Use the guide as a workflow, then assess the actual job.
What should be recorded?
Record the scope, results, limitations, observations, remedial work and the certificate or report appropriate to the work carried out.
Related guides
Solar PV Installation Explained
The electrical side of a domestic solar PV install — DC strings, inverters, isolation and DNO notification.
Battery Storage Installation Guide
Installing home battery storage safely — siting, protection, hybrid inverters and PAS 63100.
Solar PV Certificate Requirements
The electrical, commissioning and handover records that make a solar PV installation traceable and usable.
Renewables Commissioning Paperwork: What You Need
Every document a renewables install needs at commissioning — solar PV, battery, heat pump and EV charger — and who each record is for.
