4kw system?.

Spies

I don't feel like the installer really did anything wrong here, they usually send a prediction based on generation over the year, if you wanted PV to cover your load you should have mentioned that at the time or did your own research.

Being in Scotland, you'll most likely never really see much over 800w/sqm anyway, panel specs are based on 1000w/sqm so you've lost 20% purely because of your geographical location. 

Spats

arty688 said:

Also in the scheme of things over the year the number of times your panels would go above 3.6kw would be tiny if any given your location and the electric generation you are worrying about would be pence. To be fair though this should have been explained to you.

Thanks but it was never explained to me at anytime, that's why I was going nuts when I was told I would never reach 4kw at anytime after it was fitted and we had the lovely weather in July, I questioned it but told it will not happen. 

I do have a right to be angry tho. 

Cheers bud

Heedtheadvice

...and there is a benefit in having panels that could generate 4kW maxumum (normally wrotten 4kWp for peak) in that they will overall generate more output for much of the year. Consider 3kWp set of identically installed panels and they would only generate 3/4 of the 4kWp panels over the year.

Using the inverter as the generation regulation limiter means that it is likely to be more efficient too.

My 4kWp system rarely hits near 4kW generation. was calculated to produce 3600kWhours energy a year (kWh) but has actually exceeded that at approx 3800kWh a year. Even so I still need to buy 2600kWh from the grid. Rather than worry about maybe not generating 20 or 30 kWh because you do not hit panel peak output it would be much more productive (if you can!) to concentrate on using all you generate, rather than exporting it.

It is difficult to use all you generate as production time does not always match consumption time such as in hours of darkness, poor weather (especially winter) or generation when you cannot use it. Today is a good example of this. 4kWp panels but only generating 0.2kW, nearly keeping the house ticking over, fridge etc. but not enough when the kettle is switched on!

That is one reason why many are keen to have battery storage to time shift energy production to better match consumption periods though one can go a long way towards this matching by changes in your consumption pattern spring, summer and autumn. You will do well to not export 30% of what you generate.

arty688

out of interest what was your forecasted generation for the year ? As that is what the installer would have given you.

Solarchaser

Spats said:

Hi. 
System is

Ja 330w black panels x 12
Growatt 3.6kw inverter
Solo 2 monitor. 

Just had a 4kw system fitted last month, with the lovely weather we had I was expected to see on my solo 2 monitor 4kw but that never happened, it was 3.35kw tops.

From Glasgow, South facing roof 30 degree pitched roof, no trees nothing to stop sunlight, daylight. 

What should my output be guys / gals. 

The panels is 3.96kw output also MCS has given the output at 3.17 kw.

What should I achieve please, thanks and sorry for the long story trying to get in as much as possible. 

As someone also in Glasgow with a sse facing roof and 4kw of panels through a 3.6kw inverter I'd guess I'm pretty comparable to you, so I checked back my days of good generation,  and the best was 15th July


As you can see it peaked around 3.1-3.2kw.
It was hot, and so efficiency goes down a bit.
Our best months for solar tend to be April and September as its bright but colder so the panels do well, so hold on for a couple of weeks and you should see them hit the 3.6kw no bother.

Solarchaser

Actually I was looking through my records and found this day In April and I think it explains things quite well


You can see with constant sun the panels heat up and are less efficient,  but with clouds and then sun, the panels have cooled and so the sunny spells result in a higher peak.

I do agree entirely about the thing of being sold a 4kw system yet never able to make more than 3.6kw, I was pretty annoyed when I found out too, it should be explained, but never is.

It's sales right? Not quite a lie, just the omission of truth

Spats

Solarchaser said:

Spats said:

Hi. 
System is

Ja 330w black panels x 12
Growatt 3.6kw inverter
Solo 2 monitor. 

Just had a 4kw system fitted last month, with the lovely weather we had I was expected to see on my solo 2 monitor 4kw but that never happened, it was 3.35kw tops.

From Glasgow, South facing roof 30 degree pitched roof, no trees nothing to stop sunlight, daylight. 

What should my output be guys / gals. 

The panels is 3.96kw output also MCS has given the output at 3.17 kw.

What should I achieve please, thanks and sorry for the long story trying to get in as much as possible. 

As someone also in Glasgow with a sse facing roof and 4kw of panels through a 3.6kw inverter I'd guess I'm pretty comparable to you, so I checked back my days of good generation,  and the best was 15th July


As you can see it peaked around 3.1-3.2kw.
It was hot, and so efficiency goes down a bit.
Our best months for solar tend to be April and September as its bright but colder so the panels do well, so hold on for a couple of weeks and you should see them hit the 3.6kw no bother.

Solarchaser said:

Spats said:

Hi. 
System is

Ja 330w black panels x 12
Growatt 3.6kw inverter
Solo 2 monitor. 

Just had a 4kw system fitted last month, with the lovely weather we had I was expected to see on my solo 2 monitor 4kw but that never happened, it was 3.35kw tops.

From Glasgow, South facing roof 30 degree pitched roof, no trees nothing to stop sunlight, daylight. 

What should my output be guys / gals. 

The panels is 3.96kw output also MCS has given the output at 3.17 kw.

What should I achieve please, thanks and sorry for the long story trying to get in as much as possible. 

As someone also in Glasgow with a sse facing roof and 4kw of panels through a 3.6kw inverter I'd guess I'm pretty comparable to you, so I checked back my days of good generation,  and the best was 15th July


As you can see it peaked around 3.1-3.2kw.
It was hot, and so efficiency goes down a bit.
Our best months for solar tend to be April and September as its bright but colder so the panels do well, so hold on for a couple of weeks and you should see them hit the 3.6kw no bother.

Thanks mate, I only have a solo 2 monitor, so I can't give graphs. 

Will let you know how I get on in September. 

Solarchaser

Doesn't the growatt have monitoring through shine link?

I owned a growatt inverter a couple of years ago and could monitor it through that 

Spats

Solarchaser said:

Doesn't the growatt have monitoring through shine link?

I owned a growatt inverter a couple of years ago and could monitor it through that 

I don't have a dongle for it mate, just the monitor. 

Solarchaser

Fair enough mate, can pick them up for ebay for £35 if you are interested, I'm not saying its great monitoring,  just something to consider.

https://www.ebay.co.uk/itm/Growatt-wireless-Inverter-Online-monitoring-accessory-Shine-WIFI-S-stick-/264778925204?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=710-127635-2958-0