question

Armel Peel avatar image
Armel Peel asked

Solar panel wattage higher than inverter wattage

I am watching a video of a guy with a 13kw solar panel array on his house. Only problem is his inverter is only 6kw. That sounds incredibly dangerous to me. He says he was told it was not dangerous because the extra power generated will go straight into the batteries via the MPPT controller and will not overload the inverter. Can someone confirm or deny this is the case?


I know a 6kw inverter can convert a max of 6kw dc power from the batteries to ac power for use with no grid and no generator. My question is what if for instance 10kw of solar comes in one day. Will all that extra power just go into the batteries via the MPPT controller, or will it overload the inverter and possibly cause shutdowns or even explosions? Thanks for the help. Here is the video

https://www.youtube.com/watch?v=kjYMrDMYxQY

Of course I would only have ~1kw of solar on my boat with a maybe 10kw quattro inverter, so this situation would not apply to any boat setups. There just isnt enough room for that much solar on a boat. But it sparked my curiosity. I just always assumed never have less inverter wattage than solar wattage. But maybe this can be offset by the MPPT controllers going straight to the battery bank? Not really sure. Of course the MPPT controllers would have to be rated to handle 13kw which is a hell of a lot.

MultiPlus Quattro Inverter Charger
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

4 Answers
Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

I didn't watch the video but if all the PV power is connected to MPPT DC chargers there is no problem.

The 1:1 rule applies only to AC coupled PV inverters connected to the AC output of the Victron MultiPlus/Quattro.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Kevin Windrem avatar image
Kevin Windrem answered ·

The MPPT controller will provide as much power to the inverter/batteries as they can accept. It will throttle back the input from the array to avoid problems like you describe. If the batteries are fully charged, the excess solar energy would go to waste but no damage would occur.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

mvader (Victron Energy) avatar image
mvader (Victron Energy) answered ·

Think of it like this: plugging in a battery charger & a small battery (like your phone) also doesnt make your phone blow up.


even though you just connected to several Meta Watt powerplants


its the charger inbetween that only takes the power needed.


same with solar: the solarcharger in between takes only the power needed

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Armel Peel avatar image
Armel Peel answered ·

I saw three MPPT controllers. He didnt talk about the ratings of those controllers but I really dont think they are rated to handle 13kw of solar. The biggest MPPT controllers I have seen can only handle 100 amps.

1 comment
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Matthias Lange - DE avatar image Matthias Lange - DE ♦ commented ·

100A x 48V = 4800W x 3 = 14.400W

0 Likes 0 ·