Daily pv production

Gerry

11kwh today from 3kwp sw 1kw ne. ne array is waking up a bit.

Moreilly

37.6 kWh today, Kildare area south facing 22x400w. When the sun came out it ramped up well, second half of the day was fairly dull though..

DC999

https://www.boards.ie/discussion/comment/120393167#Comment_120393167

Same for me. My NW has finally left hibernation and is getting juice to 6pm in the evening now. Getting power from 7am to 6pm now - though it's low amounts and the start and end of course. We've E, small SE and NW.

ELM327

@Moreilly that's some good usage!

I've a similar array size to yours, 8.2kWp but it's south east facing instead of due south, and I "only" got 22kWh yesterday

Moreilly

https://www.boards.ie/discussion/comment/120395430#Comment_120395430

Things are starting to improve a little weather wise !!, although my wife reckons i have made a mess of the weather for the whole country as as soon as i got the panels installed Ireland's weather went to pot !

Mr Q

https://www.boards.ie/discussion/comment/120395430#Comment_120395430

19.3kWh for me yesterday with similar size. 4kW East and 4kW West but at a low pitch.

Getting close to 12 hours a day of production now.

ECO_Mental

https://www.boards.ie/discussion/comment/120393025#Comment_120393025

Just went back to look at March 2022...bloody hell it was good!! Even had a 41.5 kWh day on the last day😎 44 kWh is the most I have ever got out of my 6.1 kWp system even during the summer. Ah the good auld days

paulbok

https://www.boards.ie/discussion/comment/120393025#Comment_120393025

It certainly was, I just looked at last year's and it's looking like it will have been 50% better than this March.

The clouds bringing all this rain is killing it this year. I was doing 90% production of my 6.84kWh panels at 11am this morning, now the rain has come and it's down to 8%.

Still, at least the panels are getting a good wash ahead of the summer 😁

jkforde

31.5 today 🥳, 6.67 near max at 13:15 which was great to see. slowly dialling down the nightly charge period is very satisfying! and yes, have started inevitably eyeing up untapped roof and E & W wall space... 😆

olympicweights

30.2 here, my first time breaking the 30 mark since install late November on a 7.9kWp split E/S in Limerick Great to see battery at 30% before 8am this morning! Also seeing peaks of 5.4+ on my 4.74kWp South array which I didn't know was possible.

THE ALM

32.8kWh yesterday and looking back last March was a quality month.

We've only hit the 30's three times this month whereas last year that was 9 times with 7 days in the 40's, I think we will be short of the forecasted production of 591kWh.

@Moreilly I take it that 8.56kW is a peak reading and the Solis doesn't maintain that for any length of time?

slave1

Last March was legend, such an outlier in my (now) years of production

bullit_dodger

https://www.boards.ie/discussion/comment/120402828#Comment_120402828

Yup - although (at least for me) this March isn't terrible. I'm currently sitting at 79.6% of forecast, and there's 5 full days after today to get me ~60 or so units. I reckon I'll be within 5% or so of estimate, course we all wish it was more :-)

ECO_Mental

Decent day yesterday 33 kWh (6.1 kWp Cork) and used 87% of it which is a result. Need at least 35 kWh every day until the end of the month to actually reach my predicted... which wont happen. Forget about matching last March 😕..

micks_address

Seems like since the first week of March there hasnt been a day without rain.. had some decent periods of sunshine but don't think we've had 24 hours dry.. and it looks like the week ahead isnt promising either. Today starting out nice with intermittent cloud.. at least will cover the washes and keep the battery topped up.. what i have noticed is a few hours of sunshine in march does a lot more than a few hours in january!

bullit_dodger

Today looks OK, (bit weird around 1pm) tomorrow better, but back to crud on Weds

Sun's slant angle improves very nicely in March. March 1st sun is at 29degrees above the horizon at noon. March 31st it's at 41 degrees. That slant angle makes a big difference.

Sunrise and sunset times in Dublin (timeanddate.com)

jkforde

anyone else find that the met.ie predicted globalRadiation (tilted?) W/m² are too low compared to actual output.. so when I apply the hourly W/m² values to my ~33m² array and apply a 0.18 panel efficiency factor, the output is way lower than what is actually being generated.

now, there's a high chance that I'm being thick! 😆🤪... how are ye converting from the predicted hourly W/m² to hourly system output? is it not W/m² x array m² x efficiency factor?

bullit_dodger

https://www.boards.ie/discussion/comment/120405787#Comment_120405787

I looked at doing it that way (that "efficiency factor" method). I don't like it as panels don't work that way for everyone. Some people find that it gives them great figures, others like me...... not so much. The problem is a couple of factors. For example firstly it assumes that you have perfectly aligned "sun tracking" panels. Naturally none of us have that. Another thing is that the panels we do have are often split across different aspects and not always equally. Take me for example, I've 1.3kwp East and 3.8Kwp west. So if I had a great solar radiation value in the morning, I'd generate a lot less than the SAME value if it was to occur in the afternoon.

Best way that I found to give accurate predictions (for the day) is to sum up all the different radiation values for the day. you'll get a figure like 3600 or something, and then equate that to the actuals produced. do a 10 day moving average or something and then you will get 1000 solar radiation generates "x" kwh.

jkforde

gotcha, I thought I'd have to do something like that alright.. and re. the type of the predicted values, are they global normal then, ie maximum normal direct & diffuse irradiance? that's making sense as the predicted values are relatively high in the morning and evening since it assumes a normal incidence angle even with low level irradiance. just never thought about irradiance before this solar lark!

bullit_dodger

I believe (and I could be wrong) what it doesn't really account for is that some panels, and indeed inverters MPPT trackers, are better at dealing with diffuse light that others.

That's why I like the 10 day moving average for working out forecasts as it builds history from your specific system from the actuals obtained from those forecasts. Think it was in another thread, but it gives pretty good results.

Only 2-3 days where it was massively wrong (there around Feb 25th - where I think there might have been snow on the panels) and again on Mar10thm where the forecast was simply wrong for Dublin. Other than that, using that moving average system it does a pretty good job at forecasting.

graememk

Also it's still cold out, which makes the panels perform better too.

jkforde

https://www.boards.ie/discussion/comment/120406258#Comment_120406258

spot on, going to do that so

Gerry

10kwh today from 3kw sw and 1kw ne, not bad considering there was always some level of cloud around. Ne is now making up 25% of production. 12 hours of production now and with the clock change, more chance of offsetting peak time usage - no batteries here.

silver_sky

https://www.boards.ie/discussion/comment/120405787#Comment_120405787

I used the formula as a starting point and tweaked the efficiency factor based on actual vs estimate readings. Mine is currently 0.195.

The last week for me looks like this. Met Eireann being the calculated forecast from the solar radiation info in the API. I have an automation in homeassistant generating this daily. Aside from 21st March, other days seem to be within 10% or less.

the_amazing_raisin

27.2kWh today from a south facing 6kWp array, very happy with that

Ran almost all the appliances for free today and put 9.5kWh into the car

Problem is the car is full now so I've nowhere to put tomorrow's excess into 😂

graememk

https://www.boards.ie/discussion/comment/120408328#Comment_120408328

Rains coming tomorrow!

silver_sky

https://www.boards.ie/discussion/comment/120408328#Comment_120408328

I got 7kWh into my car today but as I upgraded recently it's a mere drop in the bucket. On my old car it would be around 30% topup. 😅

the_amazing_raisin

https://www.boards.ie/discussion/comment/120408422#Comment_120408422

Yeah I was at 71% and now at 80% where I've got the charge limit set

Will be pottering about a bit tomorrow morning so that'll drain the battery down a bit again

jkforde

once our D\N meters are swapped later this year for the RM107 unit, we can contentedly sell back metered without export anxiety! (weeeeell, as long as the bastards don't kick the legs from under the current CEG rates)

ELM327

https://www.boards.ie/discussion/comment/120408448#Comment_120408448

Yes I want one of those ASAP. Keep MCC02 but get actual export rates. I wont mind exporting then!