Spikes from Solar Panel generation on Sunny Days

DaveLister22

Yet another Solar Panel post but this one is a more complex question. I have had Panels installed and they seem to be working OK, but I get spikes in generation even on Sunny days. Average generation is OK for this time of year. So on a cloudless day I can get spikes of 800Ws or more and then generation drops almost to zero for 10 minutes or so and then climbs up again. Does the atmosphere vary the generation that much?

Dave_Fowler

DaveLister22 wrote: »

Yet another Solar Panel post but this one is a more complex question. I have had Panels installed and they seem to be working OK, but I get spikes in generation even on Sunny days. Average generation is OK for this time of year. So on a cloudless day I can get spikes of 800Ws or more and then generation drops almost to zero for 10 minutes or so and then climbs up again. Does the atmosphere vary the generation that much?

There could be several reasons for the perceived generation to change so dramatically.

If you are measuring the generation using a WiFi link there could be missing readings when there is a poor WiFi connection - my Solax inverter has a WiFi link via my router to the Solax server. I've noticed several minutes of zero recorded generation once or twice a day, but closer inspection of the data stored on the server shows that during these 'zero' times, the server has not recorded any output via the internet. The inverter continues to function correctly and power is generated normally.

Another possible reason - and this is more serious - is that your inverter can be shutting down due to high mains voltage. This would occur when you are exporting the most energy and causing the mains voltage to rise at your property. You should to check your incoming mains voltage. This should be around 230 - 240 Volts. If it is much higher, the increase in voltage due to the current you are exporting can cause the inverter to shut down due to 'a fault condition'. The inverter is probably programmed to cut out if the voltage rises above 253V. It would take a few minutes to restart after cutting out. If this is the cause, you should contact your network supplier so that they can make adjustments to the incoming supply.

Dave F