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PV panels again...

Posted: Tue Nov 01, 2022 8:36 am
by daveg
Have been monitoring PV panels production at the Elect Meter,for the settled days it has shown around 10-12 kw production except for yesterday which was 18 kw ?
Any ideas as to why the sudden uplift?
Weather has been stable......

Re: PV panels again...

Posted: Tue Nov 01, 2022 9:58 am
by trevnhil
That does seem strange.. I didn't check mine last night but previous days have been around the 12 kw region

Re: PV panels again...

Posted: Tue Nov 01, 2022 10:56 am
by johnandjen1
Strange. Yesterday mine generated 15.2kWh from a 3.72kWp system which seems consistent with previous days.

Overall though for me October was a poor month relative to 2021, generating 485kWh compared to 520kWh.

Did anyone else notice a drop off in generation last month?

Re: PV panels again...

Posted: Tue Nov 01, 2022 7:42 pm
by Anarita John
Our panels were very dusty for most of October, but after the downpours our production increased. We have 17 panels installed three years ago and 3 new panels, which are much more efficient than the original panels. However, they are facing west so, at this time of the year, produce less than the south facing ones.

In the last 12 days of October, our solar production averaged 26.22kwh per day. That is an average 1.31 kwh per pv panel. Our total production was 314.7kwh.

Last year, when we just had 17 panels (all 3 years old) for the last 12 days of October our solar production was 20.23kwh per day. That is an average of 1.19kwh per panel. Our total production was 242.76kwh.

Our 3 extra panels have made a huge difference to our production. The pv units Greenair use are one of the best for longevity. For the week of the longest day in June, our production averaged 39.9kwh. The previous year only 31.5kwh and before that 35.5kwh.

Re: PV panels again...

Posted: Tue Nov 01, 2022 8:00 pm
by trevnhil
John, I puzzle as to why you need all those panels (20), although I know you have a pool. We have just 12 panels that are about 5 or 6 years old and we only pay the standing charges every 2 months

Re: PV panels again...

Posted: Tue Nov 01, 2022 8:55 pm
by cyprusmax47
If one wants to compare electricity production from PV you have to know how much kWp your whole system is. PV-panels (actually they are called "modules" not panels in photo-voltaic installations) which were used in the last years from Green Air could be 250 Wp or 320 Wp and recently as much as 400 Wp.

Below one can see the figures for Paphos area per 1 kWp installed modules, for every month of the year, but only when conditions are perfect (South/27 degree tilt)

So if you have p.e. a 3 kWp system you will produce ca 12 kW/h per day in November, also depending air temperature, humidity, wind, dust in the air and on the modules.


Image

Max

Re: PV panels again...

Posted: Tue Nov 01, 2022 9:46 pm
by Anarita John
Trev, basically for heating the pool in winter. Unlike your home, ours is an uninsulated concrete box. Last winter we almost used all of our surplus kwh, and we did not heat our pool in the very cold weather. With those extra panels, we will be able to heat all of our house to a comfortable level, using just electricity, and our pool for most of the winter. Also, we kept our home cool during the hottest weather, with no worries about big bills. We were also thinking of the future, and being able to generate enough kwh for an electric car and a heat pump for our underfloor heating.
If we were using our diesel underfloor heating, our diesel bill would be at least €2000 for the winter.

Re: PV panels again...

Posted: Tue Nov 01, 2022 10:23 pm
by trevnhil
Anarita John.. Thanks for the explanation. With that knowledge it make more sense :-)

Re: PV panels again...

Posted: Thu Nov 03, 2022 6:09 pm
by daveg
So yet again today 20 kw recorded on the electric meter today, whereas it has been around 10-12 kw the last few days....?.

Re: PV panels again...

Posted: Fri Nov 04, 2022 6:35 pm
by Anarita John
Our solar edge app tells us exactly how much electricity we produce each day.
solaredge (900 x 507).jpg
solaredge (900 x 507).jpg (62.8 KiB) Viewed 3515 times
Today we have used 6.5kwh through the meter.
We have exported 20.1kwh to the grid.
We produced 25.84kw of electricity.

Therefore our total consumption for the day was 12.24kwh, of which 5.74kwh were from solar.

We had our pool heater on for 2 hours this morning, which raised the water temperature 1.5c from 25.5c to 27c. This used in total 7.55kwh of which 3.55kwh was solar. (4kwh through the meter) However, this also includes household use at the time which was one washing machine cycle.

Re: PV panels again...

Posted: Sat Nov 05, 2022 7:06 am
by cyprusmax47
I assume that the 3 new modules you mentioned before John were also producing electricity, what means your system size is ca 6,2 kWp installed modules.... :?:

Max

Re: PV panels again...

Posted: Sun Nov 06, 2022 10:15 am
by Anarita John
Max, yes, they are all live and producing. In June we were achieving just over the 5kw with the new modules. Probably with dust free panels we would get over the 5kw mark.

Re: PV panels again...

Posted: Mon Nov 07, 2022 11:10 am
by mark4007
cyprusmax47 wrote: Tue Nov 01, 2022 8:55 pm If one wants to compare electricity production from PV you have to know how much kWp your whole system is. PV-panels (actually they are called "modules" not panels in photo-voltaic installations) which were used in the last years from Green Air could be 250 Wp or 320 Wp and recently as much as 400 Wp.

Below one can see the figures for Paphos area per 1 kWp installed modules, for every month of the year, but only when conditions are perfect (South/27 degree tilt)

So if you have p.e. a 3 kWp system you will produce ca 12 kW/h per day in November, also depending air temperature, humidity, wind, dust in the air and on the modules.


Image

Max
Hi Max - the table you posted is helpful - I've been trying to get feel for the spread of the power production during the year. Where did you get it..

I do have one reservation in that my initial reaction was that it looks like it predicts production than are higher than I was expecting (if I am reading this right it is suggesting an average of 5.3 units per day per Kw) for a 4KW system it implies 7,738 units in a year (4x5.3x365).. whereas I have seen other websites suggesting more like 6,800 a year for Cyprus.

Re: PV panels again...

Posted: Mon Nov 07, 2022 12:53 pm
by cyprusmax47
mark4007 wrote: Mon Nov 07, 2022 11:10 am
cyprusmax47 wrote: Tue Nov 01, 2022 8:55 pm If one wants to compare electricity production from PV you have to know how much kWp your whole system is. PV-panels (actually they are called "modules" not panels in photo-voltaic installations) which were used in the last years from Green Air could be 250 Wp or 320 Wp and recently as much as 400 Wp.

Below one can see the figures for Paphos area per 1 kWp installed modules, for every month of the year, but only when conditions are perfect (South/27 degree tilt)

So if you have p.e. a 3 kWp system you will produce ca 12 kW/h per day in November, also depending air temperature, humidity, wind, dust in the air and on the modules.


Image

Max
Hi Max - the table you posted is helpful - I've been trying to get feel for the spread of the power production during the year. Where did you get it..

I do have one reservation in that my initial reaction was that it looks like it predicts production than are higher than I was expecting (if I am reading this right it is suggesting an average of 5.3 units per day per Kw) for a 4KW system it implies 7,738 units in a year (4x5.3x365).. whereas I have seen other websites suggesting more like 6,800 a year for Cyprus.
To this program only I had access when GreenAir was sole importer for Lorentz pool pumps in order to calculate which pump size and how many modules one needed for different size pools, commercial and private. (also for bore hole installations, which was much more tricky as there were as much as 50 different pumps available).

But it also shows the amount of electricity which can be achieved from 1 kWp modules in perfect conditions and not mounted on a roof with a tilt of 27 degree. (however no tracking)

In Cyprus the average for 1 kWp installed on a roof is ca 1650-1800 kWh per year. If optimizer are installed even more. Very important is also the location of the system because wind and humidity can effect the production a lot. (beside shading from clouds or objects on the roof)

Max