G98 is the UK industry rule set for connecting small-scale embedded generation to the distribution network. It replaced the older G83 standard. The formal name is Engineering Recommendation G98, published by the Energy Networks Association (ENA).
For most domestic rooftop solar installations, G98 is the process your installer uses to tell the DNO that generation is connected.
When G98 applies
G98 covers generation that meets small-scale limits, typically:
- Up to 16 A per phase nameplate current (about 3.68 kW on a single-phase supply, or about 11 kW on a three-phase supply), and
- Connection in parallel with the grid (exporting surplus power).
Exact eligibility depends on your supply, inverter settings, and DNO policy. Your installer confirms whether your system is G98 or needs G99.
What happens under G98
G98 is a notification process, not a full prior approval application like G99.
Your installer (or a registered contractor) submits a G98 notification to your DNO after commissioning, usually within a set time window. The DNO records the connection on the supply identified by your MPAN.
You should receive confirmation that the notification was accepted. Keep paperwork from your installer.
G98 vs G99 (short comparison)
| G98 | G99 | |
|---|---|---|
| Typical size | Small (up to 16 A per phase) | Larger, or above G98 limits |
| DNO process | Notification after install | Application and approval before energisation (in most cases) |
| Common examples | Many home PV systems | Large PV, some batteries, commercial |
Systems above G98 limits, multiple generators, or some battery configurations may require G99 even on domestic properties.
G98 and monitoring your system
G98 is about grid connection rules, not how you view day-to-day data. After your Fox ESS system is online in Fox Cloud, Check My Solar shows production, battery, and grid flows as reported by your plant.
Export on your dashboard depends on metering and Fox Cloud configuration, not on whether the DNO form was G98 or G99.
FAQ
Do I fill in G98 myself?
Usually no. Your MCS-certified installer or electrician registered for the work submits the notification.
Is G98 the same as MCS certification?
No. MCS is a quality scheme for installers and products. G98 is the DNO connection standard. You often need both for domestic solar and SEG eligibility.
Can a battery use G98?
Sometimes, if export and capacity stay within G98 limits and the DNO accepts the configuration. Larger storage or export may need G99.