Green Building Forum - 2023 solar generation

2023 solar generation

revor — Mon, 01 Jan 2024 16:34:45 +0000

Been comparing my 2023 generation with 2022 they are the only full years data I have. 2022 generated 6281Kwh and 2023 5347 Kwh. We peaked in May but we had a wet June so not surprised followed by very wet autumn into winter. I have 6kw of generation. Efficiency was 69% in 2022 and 58% in 2023 and used 200 Kwh more from the grid in 2022. How have others on the forum done?

2023 solar generation

djh — Mon, 01 Jan 2024 20:14:39 +0000

Here are my numbers:

year day night total generated
2016 2188 2361 4549 3,963.86
2017 2077 2405 4482 3,822.45
2018 2149 3132 5281 3,884.38
2019 2126 2642 4768 3,835.84
2020 2086 2497 4583 4,022.27
2021 2270 2798 5068 3,616.00
2022 2380 3084 5464 4,139.75
2023 2551 3780 6331 3,824.94

We have 4 kW PV. We bought an EV part way through 2022. All electric house.

Not sure what you mean by 'efficiency'?

2023 solar generation

bhommels — Mon, 01 Jan 2024 22:11:09 +0000

Compared to the PVGIS projection, 2023 has only delivered 94.5%, the worst year since installation in 2011. Second worst was 2017 with 97.9%. The 2011-2022 average performance is 104.2% (yes, it means the projection needs tweaking!)

2023 solar generation

revor — Tue, 02 Jan 2024 09:00:30 +0000

Posted By: djhNot sure what you mean by 'efficiency'?

apologies should be self sufficiency. 69% means 69 came from solar and 31 from grid. During summer typically 98/99 % as battery helps to cover non generation periods The 200 kWh more should refer to 2023.

Having been clear of any signing on issues etc now having problems had 3 attempts to do the last posting. Said was not signed in when I was. Had to come out go back in and then when I post what I had written have to sign in again.

2023 solar generation

philedge — Tue, 02 Jan 2024 12:49:40 +0000

From 2016 to 23 our figures from a 4kw system have been
16 3732
17 3547
18 3740
19 3680
20 3557
21 3661
22 3774
23 3555

MCS forecast was 3342 for the first year with a small but steady decline in output but annually we've produced between 6-13% more since installation. We went for a solaredge system with optimisers which I think accounts/contributes to the over production

2023 solar generation

Peter_in_Hungary — Tue, 02 Jan 2024 13:45:47 +0000

First year of PV, 6.8kWp system
We are on annual reconciliation, October to October so we can use the grid like a BIG inter-seasonal storage.
PV output was 0.5% over PVGIS estimate
Production was 41kWh over usage.
Total annual usage 7902 kWh.
DHW during summer, EV for 8 months, all water pumped from bore hole and usual domestic stuff.

2023 solar generation

Doubting_Thomas — Tue, 02 Jan 2024 15:16:04 +0000

My PV numbers, 4.2 kWp system in the South West

2019 3,728.82
2020 3,968.28
2021 3,617.17
2022 3,816.17
2023 3,510.23

against an installers prediction of 3,467.52 kWh/annum. Ours is also Solar Edge with optimisers, due to intermittent overshadowing by mature trees. Seems to be doing its job, but we also saw a dip last year.

2023 solar generation

djh — Tue, 02 Jan 2024 15:27:14 +0000

Hmm, don't think I've ever looked before....

MCS Cert says "Estimated Annual Generation (kWh): 2829.00" (why am I not surprised!!!)
PVGIS says 3994.77 kWh which is a lot closer (actual average is 3,888.69 kWh)

We have a couple of oak trees that reduce output in winter (reduces afternoon generation) so I can forgive PVGIS overestimating with a clear horizon. Enphase microinverters.

We're in Suffolk. Where is everybody else? Doubting_Thomas and philedge seem to have generation patterns more like each other and distinct from me.

2023 solar generation

philedge — Tue, 02 Jan 2024 18:41:48 +0000

2020 wasn't good for me but good for you and DT. I'm in NW Wales so I'm gusseing it's regional??

2023 solar generation

Mikel — Wed, 03 Jan 2024 09:31:57 +0000

Year Generation Sun hours Avg sun hrs
2012 3567
2013 3775
2014 3847
2015 3753
2016 3648
2017 3404 1278 1584
2018 3657 1417 1574
2019 3781 1436 1497
2020 3708 1509 1649
2021 3754 1486 1645
2022 3816 1648 1645
2023 3432 (1384) (1613)

3.84kW PV system. Generation data taken from generation meter, which is on average 96.3% of the datalogger reading.
Sun hours data obtained from our nearest Met Office station, which is only a few miles away from us.
I only started keeping the monthly sun hours data from 2017 onwards
Figures in brackets are data up to November.
Switched in 2020 to rolling 30yr average sun hours.
We get the peak generation in months May-Jul and any drop in sun hours for those months has a significant impact on total generation.

2023 solar generation

revor — Wed, 03 Jan 2024 17:11:09 +0000

Looks like 2023 poorer than 2022 for all. I am 14.8% down which seems a lot, Cannot find sun hours for 2023 so far.
I am N Wales (Anglesey)

2023 solar generation

Mikel — Wed, 03 Jan 2024 20:10:55 +0000

Valley station data available from here

https://www.metoffice.gov.uk/pub/data/weather/uk/climate/stationdata/valleydata.txt

2023 solar generation

djh — Wed, 03 Jan 2024 20:26:01 +0000

Posted By: revorLooks like 2023 poorer than 2022 for all.

True, but for us that's more a case of 2022 was our best ever year, so far! 2023 was just below average (which is 3889). 2021 was our worst year.

2023 solar generation

PeterStarck — Thu, 04 Jan 2024 08:40:44 +0000

When PV generation readings are submitted for FiTs payments, I assume the results eventually end up with OFGEM. Does anyone know if it is possible to access the historical data, for your own PV array. What I would like to see, is all the annual output data for each year that my array has been producing. My array was fitted in 2012 and I have lived in the property for just over 2.5 years. I have searched the OFGEM site without any luck.

2023 solar generation

sgt_woulds — Thu, 04 Jan 2024 09:30:51 +0000

To be honest I stopped recording my PV generation a while ago - building my house is more of a priority. All I do is check my Leiderdorpe occasionally to see that it is producing near or over 2500w at midday on a sunny day. Anything else and I'd be suspicious.

[The main array has terrible panels - I would never have sold them to a customer - but I was offered them brand new at £25 each, (the whole installed system cost £600 including scaffold when the average at the time was £3500) so I'm just happy to get any generation out of them!]

I do monitor the PV system at work for our carbon reporting, but only been doing that for the last two years:

2022 - 8563
2023 - 8307

This is a 9.75 kW system and one of the strings was shut down for the first 2 1/2 months in 2022 so 2023 was a bad year for generation. Given that we are likely to have more rain and more heatwaves in the coming years, (both are bad for PV panel generation) I can only see this trend continuing.

PV generation and performance are affected by many factors. Location and average sun hours are just one aspect.

Panels next to the sea generate as well or slightly better than inland, despite experiencing more morning mists that you would expect to reduce output. This I believe is due to more reflected light reaching the panels from the water.

Panels in flat areas, (Norfolk, Cambridgeshire) generate more than expected – our theory was that they experience more uninterrupted wind flow, and the panels are operating slightly cooler on sunny days.

Microinverters obviously help increase generation, (about +5% on an unshaded roof from figures we gathered), but I never considered the extra initial cost and poor reliability to compensate enough for this. Well-designed strings using tier 1 panels and a top-notch inverter is almost as good unless shading is a major issue.

It should be noted that (AFAIK) all MCS figures are still based on a single panel test they conducted when they were set up, (funded by Sharp using some (fairly average) poly panels when the trend was already towards mono cells). If this has been updated since - I hope someone can correct me on this.

That ‘test’ took no account of the variation in panel performance for different technologies or manufacturers, (they only tested a single panel from a single manufacturer) and was seen as highly unfair by the PV installation companies, (and other panel manufacturers) that existed before MCS came along to widdle in our tea.
Whilst it was very true that there needed to be some checks on the Cowboy installers who were popping up like rats from a McDonalds drive through dustbin at that time, they ignored the years of data we had compiled and took a backhander from a company with a vested interest in the outcome. It’s hard to sell a more expensive and much better-performing Sanyo HIT panel if the only figures you are allowed to quote show it as equal to any old Poly panel.

This trend continues today. I watched a video on YouTube recently that showed them removing 250w HIT panels for some ‘more efficient’ 300w mono panels. I’d love to see the comparison between the original and the new panel outputs at the end of a couple of years… I doubt there would be much difference between the two.

But it’s a win for the salesman who has gulled another sale from an unknowing Joe public.

2023 solar generation

djh — Thu, 04 Jan 2024 12:23:38 +0000

Posted By: PeterStarckWhen PV generation readings are submitted for FiTs payments, I assume the results eventually end up with OFGEM. Does anyone know if it is possible to access the historical data, for your own PV array. What I would like to see, is all the annual output data for each year that my array has been producing.

I suspect Ofgem just see aggregate data and even if they do have individual site data I don't think they would release it to you. It's only 'your' site since you purchased it; before that it belonged to somebody else. So I suspect they won't be prepared to give 'somebody else's data to you. Sorry, but that's IMHO.

2023 solar generation

fostertom — Thu, 04 Jan 2024 15:13:24 +0000

Posted By: bhommelsCompared to the PVGIS projection, 2023 has only delivered 94.5%, the worst year since installation in 2011. Second worst was 2017 with 97.9%. The 2011-2022 average performance is 104.2% (yes, it means the projection needs tweaking!)

I'd a thought 94.5%, 97.9%, 104.2% was pretty good projecting, when it's based on 10yr or whatever rolling average of a mixture of largely indirect data.

2023 solar generation

sgt_woulds — Thu, 04 Jan 2024 16:23:57 +0000

&quot; When PV generation readings are submitted for FiTs payments, I assume the results eventually end up with OFGEM. Does anyone know if it is possible to access the historical data, for your own PV array. What I would like to see, is all the annual output data for each year that my array has been producing. My array was fitted in 2012 and I have lived in the property for just over 2.5 years. I have searched the OFGEM site without any luck.&quot;

Quotes are not working for me so I'm copying and pasting :-(

PeterStarck, you could try contacting the original installers to see if they have any generation data. You might strike lucky and find that the previous owner was enthusiastic enough to send the figures to the installers and that the installers were diligent enough to store them to justify and improve their calculations.

Enthusiastic 'greenies' are generally the best source of information... :-)

2023 solar generation

revor — Fri, 05 Jan 2024 08:52:11 +0000

Posted By: MikelValley station data available from here

https://www.metoffice.gov.uk/pub/data/weather/uk/climate/stationdata/valleydata.txt

Thank you. Have looked at their figures which are provisional at moment and it looks like we had about 10% less sun hours. My generation was 15% down so might warrant some investigation.

2023 solar generation

philedge — Fri, 05 Jan 2024 09:28:33 +0000

Retrospectively tracking down a 5% loss sounds like a tall order. Have you got optimisers/microinverters with monitoring and data logging?

2023 solar generation

Mikel — Fri, 05 Jan 2024 11:47:39 +0000

@revor

I am in west Cornwall and we get very localised weather, probably due to being surrounded by sea. In summer, we can start out with a clear sky, have clouds by lunchtime and back to clear sky by late afternoon. I dont know how our weather differs from that where the Met Office weather station is located, even though only a few miles away.
I dont know whether you get similar localised weather in Anglesey.

This year the sun hours for March, April, July, August, October and November were all down significantly (approx 30-50%). July's generation was about 60kWh down from the PVGIS figure. However, although the July sun hours were 70% of average, the generation was 88% PVGIS. May was the top month with 132% of average sun hours and 120% PVGIS generation.

I only look for gross anomalies, e.g. if the percentage sun hours are higher than average but the generation is lower than expected.

2023 solar generation

revor — Fri, 05 Jan 2024 12:09:17 +0000

Posted By: philedgeRetrospectively tracking down a 5% loss sounds like a tall order. Have you got optimisers/microinverters with monitoring and data logging?

My data goes to a server in Italy I can monitor and graph on my pc and phone data every 10 mins. I can get data every 1 min by selecting at inverter. Every piece of data the inverter records which is more than what I access locally can be down loaded as an Excel file from the manufacturers server. I have had little excursion into this there is a phenomenal amount of data recorded and at moment do not have time to delve into it as it will be a another time consuming learning curve. I do not have optimisers/microinverters so if an issue with panels will only be able to get to string level.
I will need to check the figures I have got. I learnt last night that there is a weather station about 5 miles away which may have more relevant data. I was aware that this summer was getting a lot of cloud edge effect where the inverter throttles back on one of string inputs which protects the inverter from spikes. It is a strange arrangement one MPPT is 4 kw the other 2kw the 2 kw one is the one that throttles back (it drops out for a couple of seconds below 5 amps and 10 seconds above 5 amps. The manufacturer is rather protective of their information understandably so. Think there will be a contribution albeit unquantifiable from this. We had periods when it was very hot in the summer and panels were clocking over 50C which will also have been a contribution to lower output.

2023 solar generation

philedge — Fri, 05 Jan 2024 13:28:59 +0000

It was optimiser/micro inverter data logging I was asking after as its a god send for diagnostics. I guess dual MPPT inputs are logged individually so a bit more helpful than a single input.

2023 solar generation

Jeff B — Sat, 06 Jan 2024 20:39:48 +0000

Posted By: Mikel@revor

This year the sun hours for March, April, July, August, October and November were all down significantly (approx 30-50%).

These concur with what we found this year - March, April, July, August, October and November were all down significantly.

We are in west Wales and the outstanding weather feature this year has been the cloudiness. We had two very good months i.e. May and June and these compensated for the poorer six months, so that the total for the year was almost exactly bang on the average for the 12 years the system has been in place (3100 kWh).

These are the actual monthly figures:

Jan ...70 Average: 54
Feb...133 Average: 138
Mar...197 Average: 268
Apr...353 Average: 395
May...513 Average: 452
Jun...482 Average: 438
Jul... 383 Average: 425
Aug...304 Average: 362
Sep...280 Average: 280
Oct...151 Average: 175
Nov...75 Average: 76
Dec...30 Average: 35