Soldato
Wow, this is frustrating, did they not check the panel voltages before ordering it?
Solar panels and battery - any real world reccomendations?
- Thread starter GinG
- Start date
Wow, this is frustrating, did they not check the panel voltages before ordering it?
Soldato
That sucks buddy. This is what you have to weather when your at the mercy of maintaining a system. Experience and long standing companies should be able to limit this, hope its sorted quickly!
Associate
As far as I know they sent the speck needed to their supplier and that is what they sent them.
New inverter is for 2 strings, old one was single string inverter with a high voltage capacity.
Don't think the electrician is very happy as he has to come out again,140 mile round trip.
Old Fronius is huge, still looks like new.
New inverter that they fitted is SOLAX 3.0KW X1-BOOST 1PH 2X MPPT TRACKER
Soldato
Sounds me like they are both as much to blame, they must have known it was a single string setup, and should have flagged it when they received the item suggestion to place the PO for it in the first place.
Hopefully it will be sorted quickly for you and you can get back to maximum generating capacity soon. Fingers crossed for you.
Associate
If it wasn't for the fact its a rental property, I'd be up on the roof and reconfiguring the solar to be a 2 strings system, not hard to do just swap some cabling around.
Be 2 full months lost FIT payment 800/1000Kw down.
Be 2 full months lost FIT payment 800/1000Kw down.
is this a different switch to an isolator between mains and fuse board?
Associate
This is what they both had as info the Voltage is there to see.
Soldato
I think so.
If I am correct you need a switch that does two things, it disconnects you from the grid and generates a signal that the solar equipment detects and treats the same as the incoming grid
Solar looks for incoming grid and if it cannot see it it shuts down.
Thats my laymans interpretation.
So a blackout switch (UPS equivalent in effect) would automatically cut you off the mains supply and generate this "fake grid" so that the solar would be allowed to run.
Whilst of course continuing to monitor the grid to reverse the process.
I think it can be done manually a bit cheaper but you still need the fake grid signal
Not a clue. I just told the installer that I wanted to be able to run the house from the batteries if there was a power cut. Bang - £700 please.
Associate
Hi Merc - thanks for your reply. But in that config 1, 2 and 3 wouldn’t have enough voltage for the MPPT which is 150-550v for this inverter. Even when 4 comes out of shade that’s only just over 150v so realistically 5 would also need to be clear I think
Putting 3, 4, 5, 9 and 10 onto one MPPT sort of sacrifices 3 until 4, 5, 9 and 10 are clear but at least the other 5 will be generating.
I think
Soldato
Well IMO if its upto 550v then I would stick them all on one string, I don't see any gain by spreading them (I just checked mine and looks like the 150-550 is range is pretty normal) Mine will be 2x 7 panels, couldn't run 14 on one string
Although maybe the inverter would be less stressed over 2 strings, in theory should string 1 go down you would hope that you could switch to string 2 input, would clearly depend what went wrong where however
If it was me I would be asking my installer if there is any reason to not have them all on one string, that way you should get to the required voltage earlier (ie lower sun) and as the shaded panels start to come online they are adding in rather than having to get over a step point
Associate
All good points and thats what I alluded to in my fourth option. I‘m just not sure if the Tigo optimisers will work effectively if 4,5,9 and 10 are in complete shade. Good point about redundancy on the MPPT though!
Well I'm back on this again, in the wake of today's horror show announcement of course.
As the majority of my electricity usage is accounted for by a low yet constant 24/7 draw (around 300W base ALL the time, rising to 500W during the day when I'm home) I still can't see how a relatively small solar install of a couple of around 3kW wouldn't pay for itself in pretty much record time.
Are there any calculators out there which actually allow you to enter your energy usage patterns and do a proper calculation? They all seem to just assume typical usage when generating their headline "you could save..." numbers.
I feel like maybe I need to talk to a company but have no idea where to start. Anyone have any recommendations for the Birmingham/Midlands area?
As the majority of my electricity usage is accounted for by a low yet constant 24/7 draw (around 300W base ALL the time, rising to 500W during the day when I'm home) I still can't see how a relatively small solar install of a couple of around 3kW wouldn't pay for itself in pretty much record time.
Are there any calculators out there which actually allow you to enter your energy usage patterns and do a proper calculation? They all seem to just assume typical usage when generating their headline "you could save..." numbers.
I feel like maybe I need to talk to a company but have no idea where to start. Anyone have any recommendations for the Birmingham/Midlands area?
Soldato
Try and get 3 quotes.
Install costs could be high now due to demand, although how short lived that demand is I don't know.
I would aim for at least a 3.6kw system if you can, or more if possible. There are sort of fixed costs just for getting a system installed (scaffold, getting installers to care etc).
Associate
Very roughly and there are lots of variable….so you’re roughly using 3500kw/h per year. Assume solar would provide two thirds of that - 2310kw/h. Don‘t know what you’re paying but assume it goes to 45p per kw/h = £1039. So on a £10k system payback would be 10 years. The more expensive the electricity, the quicker the payback time.
Soldato
2/3rds would be quite hard to hit without a battery, with one, maybe!
Associate
I was assuming a battery - hence the £10k price I suggested.
Soldato
You could try this https://great-home.co.uk/solar-export-guarantee-seg-calculator/ but the very nature of solar makes it very difficult to predict, it depends on so many variables.
PS. No idea how accurate it is. Selecting the two battery options seems to end up with wildly different ROI periods.
Soldato
You're right, sorry, Friday + tired is not a good mix!
Install on my end still going ahead, plan for additional panel accepted and they reckon it will all fit.
The rails are up, next Tuesday panels will go up, and then the remaining cable work and commissioning should be able to go ahead.
Exciting!
Soldato
Whats the solar yield on the shortest day. Barring bad weather and other factors just wondering whats the low ebb to the yearly cycle. How many Kwh on that day just wondering for those that dismiss the point of solar. I realise its greatly improved over the years in its yield, hope one day its just default for any new build.
I was also thinking batteries are more important, because of the low peak rates available to some. Perhaps when ordering that capacity to carry over cheap energy should be the main emphasis. Maybe batteries are too expensive to just double up like that and panels arent, the excess energy to water heating gadget is obviously smart in this respect
I was also thinking batteries are more important, because of the low peak rates available to some. Perhaps when ordering that capacity to carry over cheap energy should be the main emphasis. Maybe batteries are too expensive to just double up like that and panels arent, the excess energy to water heating gadget is obviously smart in this respect