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Discussion Starter #1
We generated 50kWh for the first time yesterday from our solar PV! We have 9kWp of panels split 50/50 E/W. As they are E/W we only have a 6kW inverter.

This is way more than I was expecting at this time of year and way more than we need. We went for such a big system in an attempt to mitigate the E/W orientation... I think we over did it a bit! :D If I were doing it again I'd have less PV panels and a 10kWh battery for a similar price. My bad!

Now that they are in it is what it is... I don't think there is a lot I can do with the extra except export it which at 5p/kWh isn't too bad a result. I not only don't have much of an electricity bill but I have enough in export fees to cover that and make a profit of over £1 a day at the moment especially as I am on the Octopus Agile tariff.
 

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i have had my solar in since last July and yesterday was my second best day by just 1kWh under my record of 39.1 back just days after install, so 38.2 yesterday out of a 5.7kWh system, I think this comes back to the point I made on another thread where I was talking about the impact on temperature to the panels, basically colder is better. Interestingly the solar prediction data I have is saying today should be just as good if not a tiny but better.

I live in Wiltshire by the way.
 

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@AnthonyL Yes, PV panels always generate more when cool so this cool but sunny weather is pretty good. Later in the summer, when it is hotter, the panels will be less efficient but there is more daylight so I am still expecting to generate more in summer. Looking at the daylight hours now and what we will have mid-June I predict that a 60kWh day is quite possible from this system. That is exciting!
 

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You know you really need some batteries😁
But why? He's likely to get free electricity over the full year anyway. A profit maybe!

I'd certainly wait for 18 months to get a full picture before considering any capital expenditure.
 

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Discussion Starter #8
We already have a good idea of the winter months... this is December last year...

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We regularly use over 20kWh and on some days over 30kWh... and that is without an EV so even my 9kWp solar barely touches my use. According to these figures, even a battery wouldn't help a great deal. I already used 56% of what I generated leaving just 44%, 65kWh available to store in a battery. If I stored all of that it wouldn't touch the 533kWh I imported.

With this in mind then... a battery wouldn't win us much in winter. With so much solar available in summer and with Agile tariff rates it won't win us much in summer either.

This is all very confusing. I had set my sights on a battery believing that was the way to go to maximise our solar and reduce our bill but now that is not necessarily the case. Agile rates in winter, combined with us cutting down on our consumption altogether, may well be a better option for us.
 

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Discussion Starter #9
March looked a lot better...

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Now, this would benefit from a battery. I would have 419kWh available to store and I imported 413kWh so I could be energy neutral in March.

Obviously we don't have a full month for April yet but so far this is what I have...

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Not much bad weather so far this month so it is difficult to extrapolate forward for the rest of the summer. So yes, I have to wait at least until I have a had a full year of data before making any decision on battery.
 

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Blimey. Our South-facing 4kWp array in Yorkshire only did 22kWh yesterday, and it was in sun most of the day. It's over 8 years old though, so will be fading slowly. But we got the FiT 8 years ago too, so we get 56p per kWh combining FiT and export tariff at 50% 👍
 
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East West systems are good for self consumption and making the most out of days with changing cloud. Ours has more on West side because we are 5degrees off true East West and because we are more likely to consume electricity late spring summer autumn afternoon than at 5AM.
 

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Discussion Starter #12
Blimey. Our South-facing 4kWp array in Yorkshire only did 22kWh yesterday, and it was in sun most of the day. It's over 8 years old though, so will be fading slowly. But we got the FiT 8 years ago too, so we get 56p per kWh combining FiT and export tariff at 50% 👍
Actually then, your system is about on par with mine... almost exactly

My system 8.96kWp and 50kWh = 5.5kWh per kWp

Your system 4kWp and 22kWh = 5.5kWh per kWp

:)
 

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Indeed. But ours is 'almost ideally' sited on a 30 degree roof facing almost South, so ours should 'in theory' do better than yours as it's making the most of the peak radiance during the middle of the day. Obviously YMMV ;)
 

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9kWp, 49.24kWh yesterday. 60% East and 40% South.
I find the best days are in May and June.

The panels we installed 6 years ago this summer and I was still getting peak days of 54-55kWh last May, the same as when the panels were new. Last year's total generation was the second highest we've had, the highest being 2018.
I haven't noticed any drop off in generation over the 6 years. Maybe we're getting more sunshine.
 

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From the Scottish Borders, yesterday we made 58.217kWh - a 3-phase system with 9.72kWh of panels and a 9kW inverter. All 36 panels aligned roughly SW.
System installed December 2015.

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