Solar panels and battery - any real world reccomendations?

Similar to HungryHippo, my guys took day and a half, 3 of them, 2 on the panels/in the roof and 1 in the understairs cupboard, got most of the stuff done on the first day barring 5 panels and then finished off second day by 11 or so and one guy hung around commissioning the Givenergy stuff until about 2 when it eventually sorted itself out! Couple of hours were spent by all 3 of them getting the cable through under the floor from outside to the understairs cupboard. Certainly no complaints about the tidiness of the install thats for sure.
 
HungryHippos said:
The givenergy dongle does not work on 5Ghz, I had to disable it on my BT router (which doesn't let you split out the bands) and then re-enable once connected.
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Same for the solis equivalent.

I haven't been brave enough to re-enable 5ghz either in case it messes it up.

It's on an access point though not my main router so not really neefing much else only running on 2.4.
 
BUDFORCE said:
Same for the solis equivalent.

I haven't been brave enough to re-enable 5ghz either in case it messes it up.

It's on an access point though not my main router so not really neefing much else only running on 2.4.
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It seems OK after re-enabling it, but router reboot/power cut and it won't reconnect without disabling it again.

Don't know why BT doesn't let me split the bands out :(
 
Not sure why you'd need to disable the 5g at all. The 2.4 only device would only see the 2.4ghz network.

I've got a ton of IoT devices that are 2.4ghz only, not had any issues with my hybrid network (Deco mesh).
 
Bug One said:
Not sure why you'd need to disable the 5g at all. The 2.4 only device would only see the 2.4ghz network.

I've got a ton of IoT devices that are 2.4ghz only, not had any issues with my hybrid network (Deco mesh).
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Ideally shouldn't need to, but apparently this is a fairly common issue with some 2.4Ghz only wifi devices.

The same SSID is used for both, and I guess it can't see/connect to it on the 5Ghz so it doesn't try.
 
HungryHippos said:
The givenergy dongle does not work on 5Ghz, I had to disable it on my BT router (which doesn't let you split out the bands) and then re-enable once connected.
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Same with the growatt one, although it works fine with the dual band tplink "Deco" access points, the only issue i have is that if the server at the other end goes down for more than about 15 minutes (which it's done twice) I have to turn the access points off to force it to reconnect as it decides that no response from the server = no internet and gives up trying after a few attempts. So turning the wifi it connects to off gets it to reset the attempts.
 
Mercenary Keyboard Warrior said:
Thx @SoliD so seems for a mid/large install with battery 4-5 man days is kind of the going rate, although you guys may have literally had the same people

I wonder how long it took for @katie279 to have the install completed.
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Three days in total - although that was partly us (we were getting new roof fitted at same time, so needed to do the roof, then the batteries/inverter were a few weeks later
 
Werewolf said:
Same with the growatt one, although it works fine with the dual band tplink "Deco" access points, the only issue i have is that if the server at the other end goes down for more than about 15 minutes (which it's done twice) I have to turn the access points off to force it to reconnect as it decides that no response from the server = no internet and gives up trying after a few attempts. So turning the wifi it connects to off gets it to reset the attempts.
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If you have a Growatt inverter take a look at solar assistant, its hosted locally on a Raspberry Pi and updates in realtime... doesn't look as nice as the Growatt portal but the way the data is presented is better in my opinion.

Plus as its hosted locally there is less risk of one day all your stats and history being gone! :)

The wifi dongle continues to work incidentally so you do get the best of both worlds if you need it.
 
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If you do you will need to wire up an RS485 to USB adaptor (mine was a fiver from Amazon) which then connects to 485-2 on the inverter (set to VPP mode)

The connections for the RJ45 connection on the website are wrong, and should be Pin4 (BLUE) to B and Pin5 (BLUE/WHITE) to A on the RS485 adaptor.
 
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Ok, so I've had the solar running for a few weeks - one question is how much should I set the batteries to charge overnight?

I find on sunny days I get the dreaded 'flat line' - ie the solar has maxed out the battery and is wasting excess generation.

I've had one day so far where battery went to zero (and as on Octopus Go I pay 38p rather than 7.5p, so that'd be expensive)

Do you set your batteries to a fixed charge amount (ie grid charge to 50% overnight at cheap rate)?

Also do you adjust this regularly or just broadly with seasons?
 
katie279 said:
Do you set your batteries to a fixed charge amount (ie grid charge to 50% overnight at cheap rate)?
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As I have said previously I do my best to predict forward based on knowledge of my use, but I only have a single 8.2kWh battery installed as of now. Usage is much lower for me usually sub 10-12kWh a day, so even on a terrible solar day I can almost guarantee that the battery will cover all my needs unless I am charging the car, and that is done in the Go Faster window of 21:30 to 02:30.

Have you worked out your usage patterns yet, using your graphs, what time of day are you likely to use lots of power and when are you not? Even though I don't need to I still do heavy draw stuff like washing and tumble drying/immersion use when after 21:30 when I know it will be a terrible day the following day, and make sure the battery is fully charged to run the house for the 02:30 to 21:30 the next day. I know you can't do that due to your power use, but you can work it out, but it is all about data gathering, and you are unique so can't be compared to others.

katie279 said:
Also do you adjust this regularly or just broadly with seasons?
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Seasonal really, as if you check sunrise/sunset time, and predict generation you'll get a good idea of what state the batteries will be in once you've used the data gathered above. Sadly a couple of weeks of solar data isn't enough, but I know you are itching trying to get it all setup perfect. I suppose to some extent I don't have automation really, as I have a habit of checking at least once a day the weather, and then making sure I'll have the battery where I want it for the following day. Some people can't be bothered, but the system will pay back faster (it's being sold anyway) and I feel better knowing I did my best to lessen the load on the grid at peak times. :)
 
I think today was almost a perfect day weather wise, very consistent sunshine as todays graph shows.

What is interesting to me however is despite being poorer weather yesterday the peak power was higher.

Still need to stop that export though :p

62ek5f.png
 
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Got my first 20kwh day today, was cooler but pretty sunny. Can see some gaps though so wasn't a perfect day, same again but more sun and I could see it getting into low 20s on a good September day.
 
Wow @iwrox the second day chart is great having almost no cloud disruption!

Good start to the day here but the weather slumped off after 10am so ended up being poor. 14 kWh.
 
Yeah 28 kwh here yesterday. Obviously not at the peaks of the summer but still hitting 4.7kwh at midday peak. One for those who've had it a few years what's the drop off on a clear day in winter? What sort of potential max would you see at the middle of the day in winter with no cloud cover?
 
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