Is it possible to produce more power than the panels are rated at?

That peak may have been when weather was cold and the panels can produce more when weather makes the panels colder than the test conditions of aout 74 F.

Amorphous type panels tend to be be conservative on panel output when new. They have or had an initial "burn in" period where the rating drops fairly quickly and then settles in on a long shallow degradation curve. Not sure if mono panels have the same issue. Very cold conditions and high insolation from snow reflection will also cause panels to exceed their ratings.

Thanks for these answers . I think the weather was slightly colder on the days I recorded those3000w+ peaks also strong north winds they call the ‘mistral ‘ in france . This probably explains why on the very sunny and warmer days we’ve had this week when I was expecting the same over peaks around midday, that the levels seem to block around 2600 2700w. Whatever it feels good to be producing one’s own energy. As the days are warmer ne I’ve turned the heating off and so we are producing more than we use. In france the EDF buys the surplus production at 10cts per kWh and sells it back to you at 20cts. Maybe in the mid term when I see what our mean yearly production is( see what happens over the autumn and winter period)I may consider getting an extra battery .
thsnks again for your answers.

Cloud Edge Effect, something to think about.
Cloud-Edge Effects on Solar Arrays – SKY LIGHTS (sky-lights.org)

There are a lot of things that can push production over the rated limit.

When it's cold panels provide a lot more voltage and slightly less current. The net effect is you get more power when it's colder.
When there are clouds around, they can reflect light and cause more incoming solar radiation.
If you have bifacial panels and the back of the panel is seeing some reflection you can see more output.
If something nearby (snow on the ground) is reflecting light you can see more output.

Putting all these together, the times you are likely to see highest output is right after it rains. This is because 1) the panels are clean, 2) the panels are cold, 3) the sun comes out and 4) nearby clouds reflect light onto the panels. Often you'll see a high peak that drops slowly as the panels warm up.

Once again
Thanks for all your answers. What you have said I have been able to observe on certain days when there was cloud cover then hazy cloud then thicker cloud then clear skies. The production bumps up from 600w To 2900w very quickly then back down again before becoming stable.
I had an issue with the output circuit breaker on the inverter today, the switch was in the off position when I came in to check on the output. I opened the cover and put it back to the 'on position' and everything functions normally again. I have no idea why this happened , could it be that we were drawing too much power ? Several appliances were on , washing machine, dish washer, fridge . But this has been the case on other days at the same time(between 11: 30AM and 3PM ) with no consequence. Today is one of the days I described above, cloudy to hazy to clear sky and back again! so I' m thinking that the sudden variations may have something to do with it. I sent an SMS to the technician who just told me to do what I had already done, flip the with back on, Any user experience would be welcome to help understand the cause.
Cheers
Gead

I have a set of 100 watt panels that consistently produce more than 100 watts in the sun for a some hours at the brightest time of the day. An extra 5%.

I do nor put much into an extra 5%, even when I’m told things like, “You’ll rarely see over 80%,” even though I typically get 105% when the sun is high in the sky for between 2 and 4 hours.

To me this means I got lucky and the testing probably could have been better, or the marketing department chose not to advertise them as 105 watt panels.

Are you in a cold, high elevation climate?

The negative panel temperature coefficient is only one reason for higher output in colder weather. The maximum absolute humidity of air increases with temperature, so on cold, clear days there is less water vapor/haze in the air to block/absorb solar radiation. The height of the upper atmosphere also tends to increase with warmer temperatures, reducing solar irradiance.
Finally, it's rare to find panels that will output much (>3-5%) more than they are rated for, since their rating is based on STC and 1000W/m^2 irradiance. So when irradiance is > 1000W/m^2 and the panels are below 25C, they should output more power than nameplate.

No. I use these panels with an RV in sunny Arizona with daily temps in winter at 45 and summer is 115 at between 1000' and 2000'.

My panels simply overperform because its one of the rare times that the manufacturer "under measured" their product.

The panels I talk about are lion energy 100 watt portable panels. Can't post links here. Supposed to be designed in Germany and manufactured in Vietnam. Walmart lists them for much cheaper than other distributors.

As far as meter squared, I'm sure the size of the panels are slightly bigger than other 100 watt panels and my slightly extra output has nothing to do with efficiency. Probably 5% bigger than another 100 watt panel and that accounts for the bigger output.

EDIT: I see the OP's panels are about 4% overproducing, similar to mine, so my guess is someone is at the company is in trouble for not putting 380 watts or 385 watts on the label.

In my own case I was surprised as the panels are distributed on different rooves so I didn’t understand how they could all be at optimum output when two of the 8 face east 3 south and 3 south west. The explanation given by other members in the posts links above show that in certain conditions at the right time , for me it’s usually between 11 30 and 2pm , the diffusion of light and réflexion from clouds can cause this to occur.

IMO, your panels are probably underrated on the sticker and are perhaps 380 watt or 385 watt panels.

In my limited experience, when the sun is higher in the sky and all sets of panels point within 30 degrees of elevation, I find the output does not change that much. This is more so in the longer days of the year in my local area where the sun is overhead. I can have my 100 watt panels set up at a 30 degree elevation as measured form the ground in the summer between 11 am and 1 pm and point them South East or West, and the output will change little. It’s just that the overhead angle is nearly the same no matter what direction the panels are pointed. Kind of like you’re seeing.

In my case my panels are easy to move so I can test that easy. For you, unless you have some sort of DC disconnect going to each of those roofs, you probably can’t measure individual string output unless you have a clamp ammeter.

I don’t think mine are diffusion or reflection, since my area there are rarely clouds in the sky.

In my experience selling thousands of used panels over the years I have found I can quite accuratly aim a freestanding panel Evactly at the sun using 1, The shadow for east -west directional, and, 2 a DMM for elevation. Once you see the shadow going directly 90 degrees off the back of the panel you simply connect the leads to a DMM and do a short circuit current test. Watching the current rise and fall for elevation. There is a very substantial change in current with any more than the slightest change in elevation.

I'm having a bit of a problem from one of my 7 strings; my two Kostal Piko MP Plus 5.02 inverters can take as much as 600 V from either of their two MPPT's and 5.500 W, but for some reason one of the strings as soon as I reach 530V and producing 4.200 W, the inverter shows an error stating the DC current as being too high, switches off and restarts after a few minutes... It will continue to do so as long as the sun is providing the same power. I have tried swapping the strigs between the two inverters, but then the other inverter will fail...
What is more, I installed a brand new Piko MP Plus 5.02 and it is the same problem. How come not reaching the limit in voltage or watts it still makes three inverters fail to work? the only thing I have not checked is the amps, but on DC there is not much to calculate having the voltage and watts produced...(around 8-10 Amps).
One more thing; both my Kostal inverters have been working with their strings flawlessly for more than two years (take into consideration the third brand new inverter, having the same problem.

What can go wrong with one string, other than decaying some production percentage after two years?? I'm totally baffled..