About 9.5kWh here, peaking around 4.5kW.
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Hmm, slightly concerned about my peak then, didn’t you say your array was slightly smaller than mine (6.6kw)?
It’s 6kWp.
I suspect that the issue may be more to do with the regional weather than anything else (I’m in the SW). Also my panels are ground mounted and at a 45 degree angle which is (probably) better for low winter sun. If yours are roof mounted and at a shallower angle that might have something to do with it?
One other thought, your system seems to have a battery? Could it be that the 3kW was what the inverter generated (240v AC) while some other amount from the panels was being transferred to the battery (DC power)?
Maybe, just looked a the installer’s original proposal and with the calcs, angle from south and roof pitch etc with losses peak should be 5.8kwp. Will speak with them tomorrow but maybe time of year, just seems quite a bit less given the full sun we had today
We’re in New Zealand, in the Northland region. The system is a 8.8kW array, and set up in two orientations: 8 panels facing NW and 15 facing NE, which gives us 2 peaks and a flatter curve between the peaks, with the peak generation being around 7kw. The 54.3kWh production the other day was a record, as we are near the longest day and it was mostly clear. The next 2 days were 35.3 and 17.9. Looking back to winter in July the best day was 29.5 and there were many days at only 2 to 3kWh.
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This is how much electric the Air Source Heat Pump uses in the current cold weather. Effectively heating our upstairs using 22kwh or the equivalent of a small fan heater running continuously. The output temp is set at 39c and we get 32-34c in the radiators. It manages 17-18c in the upstairs we heat.
I could raise the water temperature to make the rooms warmer. The average December temperature has been just below 2c compared to 9c in November. December 2021 averaged 7.5C. On sunny days the weather station indicates we might generate 5kWh with 6kWp of panels.
Just musing about whether the ASHP is cheap to run. This year the downstairs is heated by the wood burner 12-13 hours a day. Its the first job I do. Last year the gas took the chill off in the morning.
Phil
Anyone seeing a drop off in how much energy is discharged from their battey when it’s colder? My Givenergy 9.5kWhr is stored in my garage, but is showing 10 degrees C. I know others who have theirs stored outside will be seeing close to outside temps.
I’ve noticed on cold evenings my charging rate has slowed down meaning it’s not as charged by morning on a cold night as it is on a milder one, I mentioned something about this about three weeks ago ‘up there’. 15 degrees seems to be the critical temperature for my system (and it’s also the recommended minimum temperature for optimum performance).
The battery management system on the battery (which I assume in your case is also Lithium based?) will manage the charge rate based on a number of inputs; state of charge, temperature of the cell being two (there may be others, I don’t know). I think the BMS might also manage the discharge rate based on similar parameters so it’s possible that on a cold day the battery would only discharge at (say) 1kW rather than the 3kW it could manage on a milder day; however I’m mostly using my battery in the evening, at peak times when there is around a 500W load or so, so this isn’t something I’ve noticed.
In the past I used to do a fair amount of off-road motorcycling. I fitted a lithium battery to a bike (to save weight) and I found that first thing on cold mornings it felt flat and often wouldn’t churn the bike over fast enough to comfortably start. If I churned it for a few seconds and then waited ten seconds and tried again, on the second attempt (when the battery was warmer) it span much faster and started. So I guess this gives an example of Lithium based battery discharge rates being temperature dependent.
Ive not found any issues so far charging or discharging. The inverter ( Givenergy AC 3.0) does both at errr 3.0Kw.
The internal battery temperature is measured and monitored by the BMS and has been as low as 13 degrees in my garage.
This afternoon i have lagged it with a hot water cylinder ( one of those red things) lagging kits. As much out of curiosity. I’ll see how tonight goes.
I’m still very new to this but noticed a couple of occasions the battery has given up its charge very quickly, like dropping from 40% down to 10 in a matter of minutes. Other times it’s been a very smooth discharge curve
I think relatively speaking they are. Obviously the ambient outdoor temperature will be a factor, as with any heating source. Now that we have learnt how to run them efficiently, our power usage has improved - they key is too set a sensible temperature and leave them to run without changing any settings. Apparently it is also best to have them set at heat only or cool only, rather than the “auto” setting to stop it heating and cooling through cycles (though haven’t tried this yet).
Our weather has been all over the place lately. Heating one night last week, cooling last night 
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Not right, and not helpfull. If you are inside the warranty period id be onto the installer.
That’s my thoughts too, and I am 
Not a Givenergy battery is it? A recent firmware update has caused a similar issue. ( not sure why a battery needs firmware, but hay…)
No it’s a Growatt, was only installed a couple of weeks ago
I thought it was almost mid summer down under! We are going through a long cold snap. Colder than last year certainly. Not what anyone wanted at these sky high prices.
Phil
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It is mid summer - but some parts of Australia are reporting snow at present - temperatures are varying significantly from day to day in some parts
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Yes, we’re getting sunny warm days and wet cool days at the moment. The metrological summer starts at the longest day (19 December), so hopefully things will pick up.
Has anyone considered the fire safety of their battery? Does yours have a built in fire extinguisher? Is it outside away from you home?
Phil
I was interested in who built the battery cells before I bought it (I used to work with battery supply for mobile phones and had some residual knowledge of which suppliers we favoured, battery was from one of these suppliers so I was happy).
It is a risk, but I’ve also got a wood burner, oil fired central heating and an EV with a much larger battery so I doubt the home battery is the biggest risk.
It’s in my attic above a room I use as a gym.
Not aware of any having inbuilt fire extinguishers, problem would be if a lithium battery of multiple kWh failed it would probably be quite a violent reaction that a fire extinguisher wouldn’t help with.
The risk of it failing doesn’t really worry me very much.
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