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Do You Need a DNO Notification?

Enter your inverter's output and supply type to find out instantly whether your balcony solar system needs a G98 notification or a G99 application — under UK grid connection rules (EREC G98/G99).

The inverter's AC output in watts, not the panel wattage. Most balcony kits are 600W or 800W. Check the inverter label or spec sheet.
If you don't know, you're almost certainly single-phase — it's standard for UK domestic properties.

This tool applies the standard UK EREC G98/G99 thresholds (16A per phase for G98). It's general guidance, not a substitute for confirming with your own DNO. Find your DNO at the Energy Networks Association.

The thresholds, plainly

Your Distribution Network Operator (DNO) runs the local cables that connect your home to the grid. When you add generation, they need to know — the rules come from Engineering Recommendation G98 and G99.

SystemRuleWhat it means
≤ 3.68kW single-phase (16A)G98Connect first, notify DNO (often within 28 days)
≤ 11.04kW three-phaseG98Connect first, notify DNO
Above those limitsG99Apply and get approval before connecting

Every standard 600W/800W balcony kit sits comfortably inside G98 — the notification is a formality, not a barrier. It only becomes a G99 application if you're stacking several systems or adding a large battery.

Thresholds per ENA Engineering Recommendation G98 Issue 2 (2025). Last verified July 2026.

Read the full DNO & G98 guide → Compare the best balcony solar kits →

Common questions

Do I need to notify my DNO for a balcony solar system?

For a standard single-phase balcony solar system of 800W (0.8kW) or less, you file a G98 connection notification with your DNO — for most plug-in kits this can be done after installation. Systems above 3.68kW (16A) per phase, or above 11.04kW on three-phase, require a G99 application and prior approval before connection.

What is the G98 limit in the UK?

G98 covers micro-generators up to 16A per phase — 3.68kW on a single-phase supply, or 11.04kW total across three phases. Below this limit you can connect first and notify the DNO; above it you must apply under G99 and get approval before connecting.