Solar panels and battery - any real world reccomendations?

a1ex2001 said:
I've been thinking about Solar panels (who hasn't with current energy prices!) it seems complicated/difficult to have over 4KW of panels that are hooked into the grid and I was wandering is it possible to have additional panels beyond 4KW that just charge your battery bank and don't feed into the grid? I have loads of roof space and obviously in the winter in particular the more panels you can hook up to a battery bank the better!
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How is getting G99 form for your DNO completed complicated? You pay your installer, or they do it free, and then the DNO give you permission of don't, there is nothing hard about it. The G99 is valid for 3+ months so you can have pre-approval for an approximate sized system, as they'll tell you what you are allowed if you ask.
 
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Journey said:
How is getting G98 form for your DNO completed complicated? You pay your installer, or they do it free, and then the DNO give you permission of don't, there is nothing hard about it. The G98 is valid for 3+ months so you can have pre-approval for an approximate sized system, as they'll tell you what you are allowed if you ask.
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I mean if the DNO don't approve it or ask for a substantial levy to upgrade the infra. I have the roof space (garage and house to probably put up something like 8-10KW)
 
a1ex2001 said:
I mean if the DNO don't approve it or ask for a substantial levy to upgrade the infra. I have the roof space (garage and house to probably put up something like 8-10KW)
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If they don't approve, then they don't approve. However as long as you are staying within the single phase limit (assuming you are single phase) then there is a greater chance of being approved than not, especially if you live in a more built up area. Also the sooner you do it the better, as more and more people add solar the less chance you will get approval.
 
Journey said:
If they don't approve, then they don't approve. However as long as you are staying within the single phase limit (assuming you are single phase) then there is a greater chance of being approved than not, especially if you live in a more built up area. Also the sooner you do it the better, as more and more people add solar the less chance you will get approval.
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What I'm asking is has anyone developed an invertor that will send the max amount to the grid (3.8KW or what ever the DNO will sign off on) but is also capable of diverting any excess power from running a much larger array connected to a battery? It seems a logical solution to me if the local infrastructure can't take the load we shouldn't be saying to people don't harness it.
 
a1ex2001 said:
What I'm asking is has anyone developed an invertor that will send the max amount to the grid (3.8KW or what ever the DNO will sign off on) but is also capable of diverting any excess power from running a much larger array connected to a battery? It seems a logical solution to me if the local infrastructure can't take the load we shouldn't be saying to people don't harness it.
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You'd probably have to speak to an installer or two and see if such a thing were possible, getting the DNO sorted isn't a huge headache though, but bigger than 3.6kw inverter/system you'd generally need one, the main sticking point seems to be the capability to send excess power to the grid above that 3.6kw mark.

Below 3.6kw the DNO just needs a notice after install, above it, and they need to approve it before the work can go ahead, with lead times currently around 3 months.

Installer may be able to isolate/limit how much can be sent to grid whilst allowing additional generation locally to feed into battery bank, but I am really not sure if that is a) possible or b) additional complexity/cost.
 
@a1ex2001 It's all doable, you can you use a G100 certified inverter which will limit how much is exported. Alternatively you can use an MPPT charger between your panels and batteries to charge the batteries directly. You then use an inverter to turn that into 240v, and as long as the inverter has a maximum output of 3.68kw all you have to do is inform the DNO once fitted - you are legally entitled to export up to 3.68kw, and if the network is not up to job the DNO has to pay.
 
Afternoon all,

First post on here so be kind!
Just had a quote for Solar and battery, just looking for some confirmation that it looks ok price wise?

House is West facing in Edinburgh, 4 bedroom and Detached with no large trees or buildings creating shadows. We have 2 kids and no EV yet, so probably fairly average when it comes to Electricity usage.

Quote
Panels 4.7kW (although we have room for 9kW) Trina Monocrystalline 390W (expected to produce 3,553kwh per year
Roof Mount Schletter & Blackbird guards
Inverter
£5,890

Battery
Hyper Inverter with Pylon Lithium Ion Batteries
3.55kWh - £3,480
7.1kWh - £4,734

Great to hear of someone with more experience than me could confirm this sounds ok and the number of panels would suit our need and which battery to pick

Thanks in Advance
 
Get as many panels as you can reasonably get away with, without it being ridiculous. Installers have some fixed costs such as scaffold and just coming to do the work, adding more panels when already on the roof won't cost a lot extra, but it will increase the usefulness. If you have space for 9kw of panels I would definitely go bigger than 4.7kw, even if you don't stretch all the way to 9kw.

Get more than one quote for sure, get several if you can.

What is your usage like at the moment? roughly how many kwh per day do you use?

You can get larger batteries or even two smaller ones to give you a larger capacity, which will work nicely with a bigger system to store more energy for usage outside of generation times.

Adding more panels and battery storage will cost some £££ though, but depending on your usage it may be worth a bit more upfront cost for reductions later.
 
Scooby2004 said:
Afternoon all,

First post on here so be kind!
Just had a quote for Solar and battery, just looking for some confirmation that it looks ok price wise?

House is West facing in Edinburgh, 4 bedroom and Detached with no large trees or buildings creating shadows. We have 2 kids and no EV yet, so probably fairly average when it comes to Electricity usage.

Quote
Panels 4.7kW (although we have room for 9kW) Trina Monocrystalline 390W (expected to produce 3,553kwh per year
Roof Mount Schletter & Blackbird guards
Inverter
£5,890

Battery
Hyper Inverter with Pylon Lithium Ion Batteries
3.55kWh - £3,480
7.1kWh - £4,734

Great to hear of someone with more experience than me could confirm this sounds ok and the number of panels would suit our need and which battery to pick

Thanks in Advance
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Price for the panels looks good to me, do you know what model of inverter it is? I'm not up to speed on battery prices to make any comment about that.

How will the panels be arranged on your roof?
 
~Divine~Wind~ said:
just enough to cover the VAT drop yeah?oh wait :(
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I had a nice email from my supplier saying I needed to pay £4k to secure the price I have been quoted for my setup, as prices are going up on the 1st June! They already have a £3k deposit! Asking further questions, led them to tell me they already have the panels, inverter and battery in stock... Still can't get a straight answer as to why I have to pay another £4k upfront. Absoutely gutted, my install date was only a week away. I really hope I don't have to start from square one again.
 
casper_uk said:
I had a nice email from my supplier saying I needed to pay £4k to secure the price I have been quoted for my setup, as prices are going up on the 1st June! They already have a £3k deposit! Asking further questions, led them to tell me they already have the panels, inverter and battery in stock... Still can't get a straight answer as to why I have to pay another £4k upfront. Absoutely gutted, my install date was only a week away. I really hope I don't have to start from square one again.
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Hmm surely they can wait a week to charge you? seems silly, it's not like you're going to duck out and forego your deposit.

When they appear and do the work you are legally obligated to pay them, they can't be so strapped for cash that they need that much additional before the job goes ahead in less than a week!

My installer on the other hand is doing my DNO application at the moment which has an expected answer (hopefully a yes) by end of July, with a 3 month wait I kicked it off about a month ago. So far they've taken the princely sum of £500 from me lol!
 
OldKitMan said:
Price for the panels looks good to me, do you know what model of inverter it is? I'm not up to speed on battery prices to make any comment about that.

How will the panels be arranged on your roof?
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Not sure of the model but it is a Solis Inverter standard string inverter which would be upgraded to a hybrid inverter if we decided to take a battery with it. The roof is about 12m Wide and 8m Height and just roof times, no windows and just roof tiles. Not sure how they will be arranged tbh

From
January 18 > Feb 13 we used 924.1 kWh 26 days = 35kWh per day
April 18 > May 13 We used 588 kWh - 25 days = 23kWh per day
 
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Flat roof? they work best at an angle if that's the case. They may need to be angled on brackets, but that will mean planning permission could be required, was discussing this point with @Ron-ski earlier in the thread.

The angle of the panels would take them above the existing roof height.

I would also gun for an inverter that can support electric vehicles out of the gate, in case you get one in a few years. Probably wouldn't add much to the cost, way less expensive than swapping it later (more labour, new inverter).
 
Scooby2004 said:
Not sure of the model but it is a Solis Inverter standard string inverter which would be upgraded to a hybrid inverter if we decided to take a battery with it. The roof is about 12m Wide and 8m Height and just roof times, no windows and just flat. Not sure how they will be arranged tbh

From
January 18 > Feb 13 we used 924.1 kWh 26 days = 35kWh per day
April 18 > May 13 We used 588 kWh - 25 days = 23kWh per day
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Guessing as it's a flat roof they probably won't bother with scaffolding, still a decent price though.

I expect the 12 panels is to avoid having to submit a G99 application - I'm assuming the inverter is a 3.6 kW model which means a G98 is all that's required.

If you want to load up the roof and fit a bigger inverter you'll need to get a G99 done in advance, installers are so busy they probably just want to get as many installs done as possible, as quickly as possible.

Bear in mind in Jan and Feb you won't generate much from your panels regardless of size although with more panels you get more in winter.
 
HungryHippos said:
Flat roof? they work best at an angle if that's the case. They may need to be angled on brackets, but that will mean planning permission could be required, was discussing this point with @Ron-ski earlier in the thread.

The angle of the panels would take them above the existing roof height.

I would also gun for an inverter that can support electric vehicles out of the gate, in case you get one in a few years. Probably wouldn't add much to the cost, way less expensive than swapping it later (more labour, new inverter).
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Sorry it's not a flat roof its 60deg, i meant to say it has nothing on it windows etc - sorry!
 
Scooby2004 said:
Sorry it's not a flat roof its 60deg, i meant to say it has nothing on it windows etc - sorry!
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I'd get a price to max out the panels, as the retail price ex. VAT for a 390w Trina panel is only £158 or less. From my calculations that means you are going with 12 panels, adding a further 10-12 is going to cost less than £1900 plus the extra fitting rails, and the upgraded inverter to an 8kW model. I'd at least go back and ask them how much the system will be extra, then you can work out how much they are charging you for the paperwork/install/delivery/warranty etc. Bear in mind that a Solis 8kW inverter is only £800 ex. VAT, so in total 24 panels and the inverter is only ~£4.6k.

EDIT: From the quote above you are paying £3.5k+ for the install/warranty and sundry items. So less than half of the cost is the hardware.
 
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Ron-ski said:
@a1ex2001 It's all doable, you can you use a G100 certified inverter which will limit how much is exported. Alternatively you can use an MPPT charger between your panels and batteries to charge the batteries directly. You then use an inverter to turn that into 240v, and as long as the inverter has a maximum output of 3.68kw all you have to do is inform the DNO once fitted - you are legally entitled to export up to 3.68kw, and if the network is not up to job the DNO has to pay.
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Thanks, that's exactly the sort of answer I was hoping for :) I'm guessing as Solar becomes more popular export limits are going to come more and more into play as the main infra was never really designed to handle any sort of consumer feed in let alone if every house on a street has large solar arrays and it seems silly to be stuck with a 4KW array just because of feed in when in reality you could generate and use more yourself.
 
Journey said:
I'd get a price to max out the panels, as the retail price ex. VAT for a 390w Trina panel is only £158 or less. From my calculations that means you are going with 12 panels, adding a further 10-12 is going to cost less than £1900 plus the extra fitting rails, and the upgraded inverter to an 8kW model. I'd at least go back and ask them how much the system will be extra, then you can work out how much they are charging you for the paperwork/install/delivery/warranty etc. Bear in mind that a Solis 8kW inverter is only £800 ex. VAT, so in total 24 panels and the inverter is only ~£4.6k.

EDIT: From the quote above you are paying £3.5k+ for the install/warranty and sundry items. So less than half of the cost is the hardware.
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Sounds a good plan, I will email him back and ask the price for the increase in panels and upgrade of inverter to 8 kWh and can support a EV as I'm sure that won't be far away either.
The roof is 240deg South West
 
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