Solar panels and battery - any real world reccomendations?

leezer3 said:

Solar panels and battery - any real world reccomendations?

I'm talking about excess power not power you need, and in the saving sessions it will be 100% worth exporting as much as you can even if you wind up using the grid later on that day, because the payments for exporting then will far out weigh the costs of importing.
forums.overclockers.co.uk forums.overclockers.co.uk

The post I think you're looking at is a 5.2kwh battery, so £1,000 odd of battery less.
Add that and take off £700 of panels and it's somewhere actually pretty close to the same ballpark figure.

Sure, in an ideal world the labour costs would be much less, but I think that's the issue I'm hitting here, in that the labour figure for 6 / 13 panels is going to be pretty similar.
Being a mid-terrace, I can only fit the 6 on the S facing roof. Might fit another 4 on the rear if I was lucky, but they didn't suggest any on there.

Doing some skimming on MSE, it seems to suggest that a battery is pointless (export the excess!!!), but interestingly the numbers he was showing me suggested the battery to be a considerable part of the benefit.

FWIW, total daily usage is ~8kw
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I can recommend the guys that did mine.
I will send you a message later with the details.

They have some kind of loyalty thing but I am not sure how it works I never really paid much attention to it.
But I will include details so you can include my name. They are Norwich based btw.

However I would consider the main systems that install are Solax based (they do do GE as well but complain it takes ages on site sometimes to get them commissioned)
 
So actually an update to my woes of batteries.
Two were replaced about 12 days ago.
The first few days didnt look great, but the last few days have shown a different picture.
I only include the days when charge is 10->100% since the SOC is pretty bonkers at times.

DateBattery whGrid whEst real SocStart °CEnd °C
27-Oct​
9828​
10442​
89.9%​
11​
20​
29-Oct​
10174​
10773​
92.7%​
14​
22​
30-Oct​
9538​
10123​
87.5%​
10​
19​
01-Nov​
9454​
10082​
83.6%​
11​
21​
02-Nov​
10227​
10848​
93.1%​
11​
20​
05-Nov​
10209​
10825​
93.0%​
9​
19​
06-Nov​
10076​
10689​
91.9%​
11​
20​
07-Nov​
10503​
11198​
95.6%​
11​
20​

They are now saying its temperatures again, which does my head in since I said if you keep delaying we will end up in winter and temps will drop but we are where we are.
If I can see 10.5kwh into battery consistently I would be pretty happy (vs the 11 usable quoted)
They do keep quoting 25C as the target temp, but I found that LiFePO4 quote 15 as basically should be capacity and by 25C they should give a bit above capacity. And as the temps increase the over capacity also increases!
Battery will likely get to 10% later today, so likely get another go tomorrow morning at 10-> 100%

The new batteries certainly seem to have fixed it, but the question is consistency now. And oddly the two original when charged to 100% before we did the same with the new ones showed a completely different charge curve to what they had always previously with a proper tail off of charge current at the end!

Fingers crossed we may be close enough that I am happy to accept :)
 
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Hmm, a second number now:
Number of Panels 6 JA Solar
System Output 2.37kW
Battery Capacity 9.60kWh Pylontech
Panel Warranty (years) 12
Performance Warranty (years) 25
Self Sufficiency (Panels only) 28%
Self Sufficiency (with Battery) 51%
Years to Pay Back 14
Total Lifetime Saving £29,907.00
Total Cost £8,394.03
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This is from Glow Green, large national bunch, who would by the looks of things use a local subbie.

No bird proofing or fuseboard mods mentioned, and similar battery capacity (the others are quoting 80% usable)

The headline figure looks better, but I wonder if there'll be addons for those....
 
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Had the batteries and inverter installed today.
Some sort of issue with the scaffold preventing the guys getting the panels up, so they'll have to go up after the scaffolding has been redone. :(
 
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My panels finally went up yesterday, have the commissioning / activation tomorrow.

They thought they would only get 6 on the garage and as it turned out 9 went on perfect. The remaining 4 have gone in the other planned position on my main roof, but now all I can think about is there is still space for 3 under the original plan for my main roof… do I get more.

The positive is I don’t need scaffolding so it’s easy for them to go up and fit more. I am just wondering if there is any point or I run things for a year and see how my 5.2kw panel / 11.6kw battery setup works for us.

Anyone wondering why we would have more panels on our garage roof instead of our house roof, it’s due to dormer windows and a skylight being in the way.
 
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JDR82 said:
My panels finally went up yesterday, have the commissioning / activation tomorrow.

They thought they would only get 6 on the garage and as it turned out 9 went on perfect. The remaining 4 have gone in the other planned position on my main roof, but now all I can think about is there is still space for 3 under the original plan for my main roof… do I get more.

The positive is I don’t need scaffolding so it’s easy for them to go up and fit more. I am just wondering if there is any point or I run things for a year and see how my 5.2kw panel / 11.6kw battery setup works for us.

Anyone wondering how we would have more panels on our garage roof instead of our house roof, it’s due to dormer windows and a skylight being in the way.
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For me, as many panels as possible - subject to inverter capacity, will help with the winter generation.
 
Freefaller said:
Ah I don't force export, I'm not after making money, but reduce how much I spend.
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Making money on export reduces how much I spend, but if you haven't the battery capacity its not worth the juggling/risk.
HungryHippos said:
I'm talking about excess power not power you need, and in the saving sessions it will be 100% worth exporting as much as you can even if you wind up using the grid later on that day, because the payments for exporting then will far out weigh the costs of importing.
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I keep missing the updates on this thread, sounds like it will benefit me to charge prior to the saving session then export at full power if it works the way you think.
 
Ron-ski said:
Making money on export reduces how much I spend, but if you haven't the battery capacity its not worth the juggling/risk.

I keep missing the updates on this thread, sounds like it will benefit me to charge prior to the saving session then export at full power if it works the way you think.
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9.5k doesn't last long with oven and other bits and pieces during peak hours.
 
Okay, so following my previous comment about having more space than originally estimated, they have quoted me £600 to install three additional 405w panels.

However they also highlighted that will take me to 6.4kW system and the inverter is 5.6kW so will be clipping in the summer.

I assume it’s still worth it for the duller months and days for £600, but any advice otherwise?
 
panels went up today :)
1G96IXX.jpg
 
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Interesting development, I had one final installer come to quote today and he suggested that they fit a Tesla power wall for the same price as the giv energy all in one now.

I had previously written it off as too expensive but I’m intrigued as to what price they come back with.
 
b0rn2sk8 said:
Interesting development, I had one final installer come to quote today and he suggested that they fit a Tesla power wall for the same price as the giv energy all in one now.

I had previously written it off as too expensive but I’m intrigued as to what price they come back with.
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What reason did they give? The All in One is what I want, but I’m a bit worried about the software issues that people seem to be experiencing with it.
 
200sols said:
The powerwall 2 has been discounted, probably to clear out all stock before the PW3 arrives.
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This basically.

The installer was very honest and said they had only installed one giv all in one so far. It also suffered from one of the reported issues after a couple of days which needed sorting. They’ve done a couple of hundred power walls which I didn’t expect given they were like hens teeth up until recently and very expensive.

I’ve got a tesla so the power wall ties into my existing set up well.
 
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