Solar PV - paid for 4kw and got 3kw

jimjames

Martyn1981 wrote: »

Hiya Jim, I chatted with Paul on a PM. He is quite northerly, up by Middlesborough, so 1000kWh/kWp is unlikely.

Ah that makes sense. We're in far South East but have very similar roof that has no shading and almost directly South, probably about as ideal as you can get from seeing our generation results.

As you say, it's interesting to see actual vs theory for capping and how it affects in practice.

defaultdriver

ajbell wrote: »

Normally you get a 3.6kw inverter with a 4kw system.
I have a solis 3.6kw inverter which maxes out at about 3.75kw.

Hi,
Do you know which model of inverter you have? I have the same inverter, I know it is 2G Single Phase. I do not have the exact model number.
I have never seen over 3.2Kw and after reading this thread am now wondering if it is my inverter.
Thanks
defaultdriver

jimjames

defaultdriver wrote: »

Hi,
Do you know which model of inverter you have? I have the same inverter, I know it is 2G Single Phase. I do not have the exact model number.
I have never seen over 3.2Kw and after reading this thread am now wondering if it is my inverter.
Thanks
defaultdriver

We have a 3kW inverter and 3kW system. The only time I've seen near 3kW is in spring when sun comes out after cloud. Generally in summer the peak is around 2.5kW

defaultdriver

jimjames wrote: »

We have a 3kW inverter and 3kW system. The only time I've seen near 3kW is in spring when sun comes out after cloud. Generally in summer the peak is around 2.5kW

Thanks for the info. I get a max peak of 3.17kW with a 4kW system. In terms of % max peak you have a slightly better max peak then my system. Did not get a chance this weekend to have a look at the inverter and find out what its capacity is.

ajbell

Mine is a Solis 3.6k and today I was getting 3.5 - 3.75kw for around 4 hours midday.
Any time there is a clear sky around midday from Feb thru Nov I get the max 3.7kw.
My house is bang on south facing with no shading.

ajbell

Good day today, at 3:33pm still outputting a constant 2.71kw.

defaultdriver

ajbell wrote: »

Good day today, at 3:33pm still outputting a constant 2.71kw.

Thanks for the info. I just checked my paperwork from the Install and I have a 3.6kW inverter (Solis)
Between 3.30pm and 3.45pm I generated 0.77kWh, so had around 3.08kW being generated.
7.15pm now and I am generating 1.2kW
I have never seen over 3.17kW. I am SW facing, but would have expected that at some point in the day I get max peak/output.
Unfortuntely I also have some shading from a chimney in the morning, so my generation does not really take off until after 11am.

ajbell

Gloriously sunny still here but because I have a south facing roof my generation has gone down to 200w.


I guess the difference we are seeing between our systems is the difference between south and SW systems.


Probably should have a different FIT system to encourage more systems that are off south facing to get peaks at different times of the day.

defaultdriver

ajbell wrote: »

Gloriously sunny still here but because I have a south facing roof my generation has gone down to 200w.


I guess the difference we are seeing between our systems is the difference between south and SW systems.


Probably should have a different FIT system to encourage more systems that are off south facing to get peaks at different times of the day.

From reading the forum I knew that we would have a difference in the generation between the different facing panels, but did not realise it would be that much.

EricMears

defaultdriver wrote: »

From reading the forum I knew that we would have a difference in the generation between the different facing panels, but did not realise it would be that much.

It will of course be balanced by a period early in the morning when the SW system doesn't start generating until a True S one is producing quite a lot (and a SE one would be heading rapidly for max output),