Solar / Battery Storage considerations

Just purchased my solar panels with Sunsynk hybred inverters…hope my 10kw system will be installed in early spring… :grinning:

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And indeed it was, a whopping 54.3kWh produced and 34.6kWh exported, giving net income for the day :sunglasses::sunglasses:

Regarding the low winter production in the UK at the moment, I’ve noticed that our production is about 50% during light cloud and even fog, and about 25% during heavy dark grey cloud, and zero during rain (or at night :roll_eyes::+1:).

Interestingly, production varies on successive sunny days. Some Google research reveals that solar radiation varies according to air pressure and atmospheric conditions, which I never new before.

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Thats a great result Mike, do you get paid for all of the 34kwh exported?
Best deals around here at present only pay for the first 10kwh exported per day

Yes, we get 14.5 cents per kWh with no export limit. Having said that, our retailer has a plan cap of a solar array less than 10kW capacity. Our array is 8.8kW and had a projected peak output of 8.2kW, but so far our peak output has been 6.8kW. We we did the install we moved 2 panels from the NE array to the NW array, which probably accounts for the difference.

How is your system going now that we are close to the longest day? Our November was the wettest on record, but we still dropped our bill from $400 to $95 and had a lot of wet and cloudy days.

We continue to be really pleased with the performance, November has been dry and sunny ( as I type that the heavens have just opened) and was the first month since our install in April when production has exceeded consumption - still doesn’t make the battery equation work though, our metrics from our 8.8kw system for November were

Solar production 1.2MWh
Consumption 1.01 MWh
We consumed 68% of our 1.2MWh produced
Electricity bill for the month was $85 - typically would have been $260
We also ran the pool heater a lot during November and we didn’t have the pool before we put solar in
Of our $85 bill, $56 was supply charge

Bit of a game now with retailers, trade off a low supply charge and receive very little feed in tariff or vice versa, almost need one electricity supplier for spring/summer and another for winter/autumn

Two of our near neighbours have just had their install completed - real pick up in interest in the suburb in recent months

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Well… Having seen @Mike_S generation figures I think in the fairness of sharing the misery I’ll show my potential figures over the next three days (and predictions which weren’t that off for the last three days)

So Tuesday and Wednesday look hopeful but the past few days have been truly dismal!

My last full 3 years of production are

  • 2019 4614KWh
  • 2020 4616KWh
  • 2021 4625KWh

Amazing how close they are, so although I do watch weather and think I’m winning when the Sun comes out, in reality it all averages out the same

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thats amazing - also good that your production is increasing each year - given that panel performance does deteriorate over time

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Perhaps that’s global warming verses deterioration :disappointed:

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Wow interesting!!! what size is your system and what part of the country are you in…

This is better for December in the uk isn’t it? Was full sun nearly all day. Peaked at just over 3kw though for a 6.6kwp array but guess that’s low sun this time of year?

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15.2 Kwhr from my 16 panels ( 400w each) set up in Kent today.

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A mere 3.3KWh in the north west :disappointed:, although it was enough to get my water to 60degrees. But we are due some sunny weather for the next three days - Yipee

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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.