kWp query

JohnW
Posts: 53
Joined: Fri Jul 22, 2022 2:31 pm

kWp query

#1

Post by JohnW »

Hi Guys
Well the panels were finally switched on Friday afternoon and are generating, just over 11kW yesterday, and I'm trying to get to grips with the info I'm getting from the inverter.

I have 14 panels in 2 strings, 7 panels East facing and 7 West. Each panel has an STC max rated power of 380W and NOCT of 287W so 2,660kkW and 2009kW respectively per string, I think!

The inverter doesn't show two strings, just a total string capacity of 2.000kWp. I would have expected the figure to be at least double this, or am I wrong? Does it matter what capacity it shows?

As a newcomer to PV I'm still on a steep learning curve.

Thanks in advance for any advice
JA Solar panels 14 x 380W East/West arrays
Solis S5-EH1P hybrid inverter
Pylontech US5000 battery x 1
Pylontech US3000C batteries x 4
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Joeboy
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Re: kWp query

#2

Post by Joeboy »

You have a max cap of 380Wx14= 5,320kW array size. Your inverter will show the Watts being generated at a point in time and a total for the day. There will be other data too. It's getting late in the year and 11kWh isn't too shabby. One of my systems is also on a W/E split and similar size to your own. It generated 6.2kWh yesterday.

There are prediction models out there that will with your location and panel orientation and angle give a close estimate for your expected annual generation. Welcome onboard and congratulations on PV power on switch being engaged, its a great place to be!

You are now going into the shoulder months and you will see a huge drop off in the coming months which will turn around in March. Just the nature of the beast, where are you? Send Nowty a PM with your system details and he'll add it to the collective. :)
Last edited by Joeboy on Sun Oct 09, 2022 11:31 am, edited 4 times in total.
19.7kW PV SE, VI, HM, EN & DW
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nowty
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Re: kWp query

#3

Post by nowty »

The short answer is its October and you've got an East West system. The sun is getting lower and lower in the sky each day so the strength of the sun is less and the angle to your panels become less optimum.

I generated 39kWh yesterday, but I've got 13kWp of panels, I'm on the South Coast and over 5kWp of my panels face SSW.

You've got 5.32kWp of panels and are in North Wales, so I'd say that's about right.
18.7kW PV > 109MWh generated
Ripple 6.6kW Wind + 4.5kW PV > 26MWh generated
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nowty
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Re: kWp query

#4

Post by nowty »

This is what you should expect on a monthly basis, note the daily average for Oct is about 6kWh a day so you generated almost double that yesterday.
5.32KWp on an E/W system in North Wales.

Image
18.7kW PV > 109MWh generated
Ripple 6.6kW Wind + 4.5kW PV > 26MWh generated
5 Other RE Coop's
105kWh EV storage
60kWh Home battery storage
40kWh Thermal storage
GSHP + A2A HP's
Rain water use > 510 m3
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nowty
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Re: kWp query

#5

Post by nowty »

Joeboy wrote: Sun Oct 09, 2022 11:24 am Send Nowty a PM with your system details and he'll add it to the collective. :)
He's been on the secret list ever since he bought the kit. :twisted:

But I had him down as an annual yield of 4.5MWh but now I know he's got an E/W, I've had to reduce him to 3.8MWh. :evil:

Maybe he can find some room in the garden for a small south facing ground mount. ;)
18.7kW PV > 109MWh generated
Ripple 6.6kW Wind + 4.5kW PV > 26MWh generated
5 Other RE Coop's
105kWh EV storage
60kWh Home battery storage
40kWh Thermal storage
GSHP + A2A HP's
Rain water use > 510 m3
User avatar
Joeboy
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Location: Inverurie

Re: kWp query

#6

Post by Joeboy »

nowty wrote: Sun Oct 09, 2022 11:44 am
Joeboy wrote: Sun Oct 09, 2022 11:24 am Send Nowty a PM with your system details and he'll add it to the collective. :)
He's been on the secret list ever since he bought the kit. :twisted:

But I had him down as an annual yield of 4.5MWh but now I know he's got an E/W, I've had to reduce him to 3.8MWh. :evil:

Maybe he can find some room in the garden for a small south facing ground mount. ;)
Can't go wrong with that!
19.7kW PV SE, VI, HM, EN & DW
Ripple 7kW WT & Gen to date 19MWh
42kWh LFPO4 storage
95kWh Heater storage
12kWh 210ltr HWT.
73kWh HI5
Deep insulation, air leak ct'd home
Zoned GCH & Hive 2
WBSx2
Low energy bulbs
Veg patches & fruit trees
JohnW
Posts: 53
Joined: Fri Jul 22, 2022 2:31 pm

Re: kWp query

#7

Post by JohnW »

Thanks guys, I get that at this time of year input will be reduced, and I was pleased with >11kW yesterday it's just that the max string capacity figure of 2.000kWp doesn't change, it seems to be a parameter that's been set at installation, as it's on a screen that shows the system details, not live or historical generation data. It may not matter and I'm being unnecessarily picky

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JA Solar panels 14 x 380W East/West arrays
Solis S5-EH1P hybrid inverter
Pylontech US5000 battery x 1
Pylontech US3000C batteries x 4
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Fintray
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Re: kWp query

#8

Post by Fintray »

JohnW wrote: Sun Oct 09, 2022 12:18 pm Thanks guys, I get that at this time of year input will be reduced, and I was pleased with >11kW yesterday it's just that the max string capacity figure of 2.000kWp doesn't change, it seems to be a parameter that's been set at installation, as it's on a screen that shows the system details, not live or historical generation data. It may not matter and I'm being unnecessarily picky

Image
I wouldn't worry about that figure as it will not affect the output from the system.
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JohnW
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Re: kWp query

#9

Post by JohnW »

Thanks Fintray, I'll sleep easy tonight. I'm amazed how much power's being produced. 5.5kW so far today and the weather is dull.
I just need to get the batteries sorted now, and a smart meter fitted (next Saturday) to start exporting.
JA Solar panels 14 x 380W East/West arrays
Solis S5-EH1P hybrid inverter
Pylontech US5000 battery x 1
Pylontech US3000C batteries x 4
spread-tee
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Re: kWp query

#10

Post by spread-tee »

Pedant alert!!!

5.5kW so far today

That should be 5.5kWh so far today.

As I am sure you are aware kW is power or the rate that energy is flowing, kWh is the amount of energy that has flowed.

Usually it is obvious what is meant, but not always..

Sorry :D

Desp
Blah blah blah
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