Friday, 18 September 2026(forecast)
Solar generation in Derry, Friday, 18 September 2026
Overcast in Derry. A 4kW install would still produce about 3.8 kWh of free electricity today.
4kW system
Typical 3-bed NI home (10-12 panels)
3.8 kWh
£1.29 of electricity
6kW system
Larger home, EV owner, or heat pump
5.8 kWh
£1.93 of electricity
Weather on the day
- Sunshine
- 1.4 h
- Cloud cover
- 92%
- Max temp
- 17.5°C
- Solar radiation
- 1.23 kWh/m²
Want this generating on your roof?
Compare quotes from MCS certified installers in Derry. Free, no obligation, and quotes for the same system routinely differ by more than £1,000.
Recent days in Derry
How we worked this out
We used daily shortwave radiation data for Derry from Open-Meteo and applied the standard PV yield model:energy = radiation × system kWp × performance ratio. The performance ratio is 0.78 (accounts for inverter and temperature losses, orientation and soiling). Electricity is valued at 33.5p/kWh, the tracker's fixed assumption. Power NI's standard credit rate is 32.100p, so a Power NI household should read these savings as slightly high.
Figures are an estimate based on forecast conditions and a representative install. Actual generation varies with roof orientation, shading and hardware.