Daily pv production

YFlyer · 23-09-2022 11:15am

https://www.boards.ie/discussion/comment/119653146#Comment_119653146

Was it much more cloudy the previous three days? 21kWh is impressive.

bullit_dodger · 23-09-2022 11:55am

https://www.boards.ie/discussion/comment/119654313#Comment_119654313

And there in is the problem with "winter" and off grid that we were talking about ELM327. You could have 4-5 days of that in a row. Very difficult problem to solve even with 20Kwp of panels, even with big banks of batteries. There is always a solution, but just wanted to highlight how bad it is on some of those dark winter days. I've seen lower than 0.7 Kwh myself :-(

ELM327 · 23-09-2022 11:57am

I'm currently pulling 7.0kW into my inverter. Not every day is like that. If you have 100kWh of battery you can live on 2-3 bad days with one good day of supply.

(Just to clarify.. it was 7kWh yesterday not .7)

deravarra · 23-09-2022 12:45pm

https://www.boards.ie/discussion/comment/119654614#Comment_119654614

What would be the cost of 100kWh battery?

ELM327 · 23-09-2022 12:57pm

Well i paid ~10k for 20kWh installed by someone. And that includes the inverters and mounting and labor for multiple staff etc.

I'm now seeing that I could have bought and DIY'd it for a lot lot less, 3-5k per 20kWh. 15-25k for 100kWh of batteries.

Or simply, replace one of our EVs with an ioniq5/ev6 and wire up some V2L to charge batteries.

bullit_dodger · 23-09-2022 12:58pm

https://www.boards.ie/discussion/comment/119654614#Comment_119654614

That 7Kwhr over 0.7 Kwhr makes a big difference! :-) LOL

In theory your right, not every day is like that. My telemetry on the website only goes back to Dec20th, but here's my production for the last 10 days of Dec.

This is off 5.3Kwp. Difficult to fill a 100Kwhr battery after taking out what the house might need (20Kwh?) even if you have 50Kwp in panels. There just simply isn't enough sunshine on those short dark cloudy days. Course as mentioned above, there's usually a solution and if you managed to couple that production above with a (decent) wind turbine, you might start to get close.

Still think that a fully off grid solution is non-workable, but anything is doable - just getting the right balance between cost and reward.

ELM327 · 23-09-2022 1:02pm

Yes that mid november to mid jan period is the challenge. I still reckon it's doable, adding wind and hydro would be necessary.

I'm at over 10kWh today, which is approaching the sum total of the last 2 days together! (~13kWh)

slave1 · 23-09-2022 5:28pm

Nov to Jan is brutal, I'll be going from over a MWh a month to 300kWh for Dec and Jan together (obviously depends on your orientation and panel angle)

slave1 · 23-09-2022 6:14pm

Better day today, 37kWh, 6.4 to house load, 11.1 to water, 15.9 to EV, 3.6 exported

bullit_dodger · 23-09-2022 6:29pm

11.1Kwh to water?! Holy smokes batman! How big is your tank?

slave1 · 23-09-2022 6:38pm

Not huge, would have been emptied and reheated again throughout the day

DC999 · 23-09-2022 6:43pm

What you sent to your hot tank today is close to what our PV generated today. I've PV envy as usual :)

Decoda · 23-09-2022 9:11pm

After communication issues with the MyEnergi servers all week I finally get access to data again. A lot of big cloud around so plenty of dips and troughs throughout the afternoon. Finished with 29.1kWh (from an 8kwp system with a SE / S orientation)

AckwelFoley · 23-09-2022 9:19pm

Not too bad today. Could have been much better but 2- 3 hours of peak time was destroyed by bastard clouds

Came out with 15.9 at ten end

6.5kw South facing

deravarra · 23-09-2022 11:03pm

Got my BER results back. Previous BER was a C3. Today I got the BER update and it came in as a B1.

In the interim, I got my heating controls upgraded and house zoned; went to a condensing oil boiler (grant vortex); new dhw cylinder (kingspan ultrasteel); new composite front door; wood pellet stove replaced open fire; and the 4.4 kWp system.

Delighted.

Decoda · 25-09-2022 8:41pm

Really dull day of with lots of cloud cover but still generated a respectable 14.2kwh (from an 8kwp system with a SE / S orientation). System went live last Monday and total generated in 7 days was 124kwh. If only every week for the next 6 months could be like that.....

slave1 · 25-09-2022 10:05pm

Looks dull for remaining of month, solar winter is upon us

DrPhilG · 26-09-2022 12:43am

Muck day today, forecast for the next few days is the same.

fuse · 26-09-2022 9:51am

I have an East/West split, installed at the start of the month. I was playing around with charts in Home Assistant trying to get a better view of how the two sides perform through the day. 24th probably shows the most typically expected result - East (orange) gets the morning sun and west (blue) takes over for the evening. On a dull day like yesterday, they both pick up the ambient light.

East has 6x 405w panels. West has 8x 405w panels.

AckwelFoley · 26-09-2022 9:55am

Yea. The ambient light in the evening cracks me up. I'm south facing, even in the evening it can do 300w 400w when the sun isn't directly at the panels. 300w isn't much but it's a few lights etc..

micks_address · 26-09-2022 9:56am

https://www.boards.ie/discussion/comment/119657804#Comment_119657804

We are currently b3 and adding 6.5kw solar and battery.. interested to see how that might affect the BER

slave1 · 26-09-2022 10:13am

there's a fixed formulae for the impact on BER with the addition of PV panels....good luck searching for it though.

paulbok · 26-09-2022 10:16am

https://www.boards.ie/discussion/comment/119665627#Comment_119665627

I went from a D1 to a B3 when I added 6.84kwh of panels, the battery isn't considered in the calcs.

ELM327 · 26-09-2022 10:20am

Doing quite well so far today, pulling since before 845 (when i got up lol)

viewofthehill · 26-09-2022 2:07pm

Is there a reason why the energy app would be showing a large discrepancy between the charged and discharged values? For the current month I am seeing a charge of 125.07 (Aug 105.09) and a discharge of 150.94 (128.19) on a 5kWh battery. Surely if it were down to losses the difference should be the other way

Also I am assuming that the self use figure (not percent) is calculated as one of the following:

Production - (Grid feed in + Energy Charged)

Aug. 856.01 - (514.64 + 105.09) = 236.28

Sept 649.46 - (320.26 + 125.07) = 204.13

Consumption - (Purchased Energy + Energy Discharged) =

Aug. 354.36 - (73.45 - 128.19) = 152.72

Sept. 376.74 - (107.81 + 150.94) = 117.99

Does any one know why there is a big discrepancy in these figures? In both cases the discrepancy is bigger than the charging/discharging difference.

SD_DRACULA · 26-09-2022 2:45pm

So if it is on a Solis it looks like it's not great at detecting small grid imports on fluctuating power requests, i.e. when you cook stuff, the hob goes and on off a lot and it will will ever so slightly pull from the grid by the time the inverter/battery kicks in.

Solis app can show 0kwh imported for that day but I have a CT clamp on the mains and that's not what I'm seeing, it's missing anywhere from 1-2kwh times 30 days etc.

Battery difference is about 20% which is expected but I also expected the values to be flipped, not sure they are not.

viewofthehill · 26-09-2022 3:09pm

@SD_DRACULA I was thinking the same about flipping the charge and discharge butt that still leaves roughly 25kWh as the difference.

I have a Sofar inverter with a solarman stick attached. Below are two screenshots from roughly the same time. In the second screen the production is showing at 90kWh more than the historical data so self used and production are the same figure as expected but battery discharge is still showing as 25kWh more than charged.

An export of the raw data is showing a cumulative consumption of 355.10 at the end of August and 732.80 today a difference of 377.7 roughly equal to that on the first graph. It doesn't make sense unless they are calculating Total Consumption from Production (Self Use) + Purchase + Discharge.

SD_DRACULA · 26-09-2022 6:28pm

It's hard to tell without seeing the raw data to be honest.

But today 18kwh and the met prediction was spot on 😁

Decoda · 26-09-2022 7:53pm

19.11kWh generated and achieved our highest production rate so far of 6.19kWh. Still waiting for 4 optimisers to be fitted so it could go a little higher yet.

deravarra · 26-09-2022 8:32pm

https://www.boards.ie/discussion/comment/119665627#Comment_119665627

Would there have been any other improvements made since the previous BER?

I had a good few small improvements.

What was quite surprising was that the BER advisory report suggested that an A1 rating was possible with some improvements - namely window replacement.

Daily pv production

Comments