Which quote to choose help!

[Nicky pies]

Hi all, I’ve been a lurker for a few months while toying with the idea of having solar installed. I’m now taking the plunge and have 2 final quotes…I had decided on going with an established local company (20 years in the game) but a newish national company I had spoke with have come back with a lower offer tonight, problem is I’m due to sign contracts tomorrow, so need to make a quick decision, so any advice will be appreciated. The two quotes are follows

Local firm

Prices for both system split array

20 x Perlight 400kw panels
2 x 6.5kw Growatt batteries
Birds protection
1 Iboost
8.0kw Growatt inverter

£17,935

National Firm

Solar Panels
Trina
7.7 kW Total Solar Power
20 x 385 Watt Panels
6,906 kWh per year

Inverter
Sunsynk
8 kW Total Inverter Rating
1 x SUNSYNK-8K-SG02LP1

Battery
Sunsynk
10.24 kWh Total Battery Storage
2 x Sunsynk 5.12kWh

£15,500

Help please

 

[Murdoch]

National company sounds warning bells. This almost certainly means the install will be done by sub contractors , and what happens when it goes wrong or the installation is poor?

 

[Nicky pies]

Yeah the reputation is a main concern for me, they have 8 reviews on their Google rating ‘All seasons Energy’ based in Sheffield. I can’t find much information on SunSynk battery or inverters either, just it’s £2.5k to consider saving with them..

 

[Murdoch]

Company appears to have been incorporated in February 2021

Hum

 

[Nicky pies]

Company appears to have been incorporated in February 2021

Hum

Yeah, cheers didn’t think of checking company house. Not great. Think I’m leaning towards the old saying buy cheap buy twice or in this case have a nightmare if things go wrong.

 

[Nicky pies]

Hi, sorry to drag this up but wondered on thoughts that the installer has said it is not a 8kwh Growatt inverter but a 5kwh apparently Growat don’t do single phase inverters that size and that it was an error. Will 5kwh be sufficient for an 8k Array? Any help appreciated.

 

[binky]

Hi, sorry to drag this up but wondered on thoughts that the installer has said it is not a 8kwh Growatt inverter but a 5kwh apparently Growat don’t do single phase inverters that size and that it was an error. Will 5kwh be sufficient for an 8k Array? Any help appreciated.

I wouldn't, too much like strangling the system even on a split array.

 

[Nicky pies]

I wouldn't, too much like strangling the system even on a split array.

Thanks for the reply Binky, When you say strangling, can you expand a bit for me? Just if necessary I’ll get onto them before install on the 31st. Also is it in anyway hazardous? My inverter and batteries will be in the loft if that makes a difference in terms of fire relating to the strangling.

 

[Nicky pies]

The inverter is a 6kwh Inverter, would that be much of a problem still? Installer says it has a 8000kw output.

 

[Mrjmegson]

It's a huge drop is 8kw to 5.

I think Binky means that you are strangling 8kw down to 5kw, which is too much of a drop.

You prob won't ever reach 8kw, or rarely, but even on duller days you'll be losing a lot of power with only a 5kw inverter.

I'm using 6kw inverters on a 6.4kw PV array. It probably won't hardly ever get strangled.

 

[Mrjmegson]

The inverter is a 6kwh Inverter, would that be much of a problem still? Installer says it has a 8000kw output.

It's input that's the issue. What is the input?

 

[Nicky pies]

20x400kw Perlight panels 8.0kwh

 

[binky]

Thanks for the reply Binky, When you say strangling, can you expand a bit for me? Just if necessary I’ll get onto them before install on the 31st. Also is it in anyway hazardous? My inverter and batteries will be in the loft if that makes a difference in terms of fire relating to the strangling.

It won't cause a fire. What is the roof pitch and orientation?

 

[Nicky pies]

It won't cause a fire. What is the roof pitch and orientation?

It says roof pitch 30

-62 from south on first input

130 from south on second input

On the calculations that were sent it says the estimated output is 5600kwh

 

[Nicky pies]

It says roof pitch 30

-62 from south on first input

130 from south on second input

On the calculations that were sent it says the estimated output is 5600kwh

Guess I have just answered my own question?

 

[binky]

Guess I have just answered my own question?

With those orientations, the inverter won't be maxed out very often, if at all, assuming it's equal size arrays on each roof

 

[Nicky pies]

With those orientations, the inverter won't be maxed out very often, if at all, assuming it's equal size arrays on each roof

It is equal yes, thanks for the help.

 

[Mrjmegson]

20x400kw Perlight panels 8.0kwh

That's a bloody big roof to be able to fit 20 x 400kW panels up there. How big is a 400kW panel, at max efficiency of 22%, they must be the size of a football pitch.

Lol. Sorry, couldn't resist.

 

[johnb2713]

Hi, sorry to drag this up but wondered on thoughts that the installer has said it is not a 8kwh Growatt inverter but a 5kwh apparently Growat don’t do single phase inverters that size and that it was an error. Will 5kwh be sufficient for an 8k Array? Any help appreciated.

Use the SPH6000, 6kW Growatt Inverter, a bit nearer match to your PV. I would also reconsider EDDI in place of iboost which seems to have some reliability and support issues. If you're considering EV, a ZAPPI charger integrates perfectly with the system and works with EDDI energy diverter seamlessly.

 

[Nicky pies]

Use the SPH6000, 6kW Growatt Inverter, a bit nearer match to your PV. I would also reconsider EDDI in place of iboost which seems to have some reliability and support issues. If you're considering EV, a ZAPPI charger integrates perfectly with the system and works with EDDI energy diverter seamlessly.

Thanks John, great that’s the inverter that is being fitted I’d made an error on that post you quoted, I’ve already been reading your posts on Eddi and I’ve switched my iboost from the quote out for Eddi. EV purchase is a couple years down the line for us but zappi definitely part of the plan, thanks for the advice, hugely appreciated