Does this look right?

[Allanm]

We have a single 100w ( so I was told when we bought the van) panel on the roof, a Victron 75/15 mppt controller and 2x LDF 90 batteries. We have regularly had up to 75w shown as being produced by the panel but yesterday, it showed 109w!
Does this look right? It’s showing a max of 91 w today, currently generating 68w (3.7a)

Or is it a little over ambitious?

 

[Lenny HB]

Sounds high for the north of France at this time of year, perhaps your panel is 150W.
What are the dimensions of the panel?

 

[Allanm]

It was at Canterbury P&R this morning!
Can’t measure the panel at the moment as we aren’t home till Wednesday.
Currently in sunny Ramsgate where it’s showing up to 80w.

Rough measurements, without climbing on the roof are 100 x 70 cm.

 

[gus-lopez]

Rough measurements, without climbing on the roof are 100 x 70 cm.

I'm sure that is a 100w.
I've just changed one on mine a few minutes agi which was 1010x 670mm = 100w

 

[Jaws]

The ratings of panels seems to be rather guesswork than factual.
I suspect the figures given by manufacturers are just the minimum rather than the actual.. covers their bums so as no one can say they paid for an x output panel and it only gives y output..
I would just be happy !

^{_{Subscribers  do not see these advertisements}}

 

[Abacist]

All these different readings e.g. amps, watts, amp hours etc are just adding complexity.

You can put a voltmeter on the solar controller input from the panels and see what they are producing in terms of volts which will vary according to the angle of the sun in the sky and cloud cover etc. You can also check the output of the controller to be sure that the controller is duly controlling the voltage. After that I just accept that they work and let them get on with it. I have 2 X 130 watt solar panels and they are adequate to power/charge my hab batteries when I am on site. As long as the voltage in the batteries is over 12.5 volts I'm happy though that would be a just before bed reading and then they should go up to 13 volts as they charge during the day. If the voltage starts to drop more quickly then the chances are the batteries are getting towards the end of their life or if they don't get back up to 13 volts.

 

[autorouter]

It's 109 watts peak power. It might have only been for a few seconds. For example, maybe the panel caught a reflection from a window in a nearby building. Such things happen - when the Shard in London was first built, cars were actually damaged by the concave reflecting surface concentrating the sun onto them.