Solar Quotes

mavii

Hi

I was wondering if I could get some advice. I've had two quotes for solar for my house that are quite different and I'm not sure how to compare them.

I live in Bishop's Stortford area and have a large rectangular roof that is almost exactly south facing. There is one large tree that doesn't shade at the moment, but may cause some shade nearer winter.

Quote 1 - SolarEssence - done via call and googlemaps - 4kW system of 16 250W Mono All Black ECO-250M60 panels with GW 3600-UK inverter and iBoost included - total £5,908

Quote 2 - SolarBarn - excellent visit to the house to view - 4kW system of 16 LG 250 panels with SolarEdge inverter - £8,430 with iBoost extra £441.

Does anyone know what these panels and inverters are like so I can try and assess the benefit of the more expensive system? Or anyone used either of these companies?

Any advice gratefully received,
mavii

tunnel

Hi,


I've seen standard 4kWp systems now being quoted at around the £5-£5.5k(something without shading) so that should give you an idea of where to aim for, adding solaredge doesn't increase that by £3k. Aim for £6500 with solaredge (and iboost) if you have shading.


You may get away with a standard 2 string inverter if the winter shading only does lower roof or one side of a roof, just give us a bit more info so we can get an idea of the shading prob(if any)

mavii

Thanks for the quick response. Shading is one large tree (sadly evergreen) roughly in line with the middle of the roof, so I guess the issue would be shading of bottom half.

The tree is not on my property so I'm not sure how I can estimate easily what the shading will be like in spring/autumn/winter (no issue at the moment).

Will talk to the people with the higher quote and see if they will negotiate.

Martyn1981

Hiya mavii, and welcome. Keep bouncing back and for between here and the installers, and we'll be able to offer some general PV'er advice.

Also check out the PV FAQ for general info, and section 5 to work out (roughly) your annual generation:

https://forums.moneysavingexpert.com/discussion/3872445

Both tunnel and myself have multiple systems, and both of us have string inverter systems and SolarEdge system.

SolarEdge is brilliant, but might be overkill if shading is only minimal, and during winter. It would add about £500 to the cost, but more importantly, means having a PO (power optimiser) attached to each panel. These are very robust, and have 25yr warranties, but you need to consider access/costs if one needs replacing.

Two strings, top and bottom rows of panels, as tunnel suggests would be much simpler if shading is minimal.

Tried to look up the Goodwe inverters, found their UK site and the inverter range:

http://www.goodwe.co.uk/html/list_1430.html

but couldn't get into any of the "MORE>>" pages, so no idea what their efficiencies are. Also noticed that the contact us (on the .co.uk site) is for China, Germany or Australia ....... hmmmm. Minor issues, but maybe worth asking for prices with other inverters if any of this worries you.

Keep chatting. All the best.

Mart.

mac2008

Regardless of kit differences, I agree that the 2nd quote is just too expensive. Some slight efficiency gains are not likely to outweigh the additional outlay of nearly £3k.

Did either leave you any calculations about yearly outputs or payback period?

scepticOfCheltenham

We have just received a quote from SolarEssence for £5.8k for a 4kW system. It is the only quote we have had so far that details the equipment they are proposing and that gives a proper financial work up. Certainly beats the Big Green Co, who are asking £13k with no list of parts and a system (cost) prediction sheet that did not add up.

tunnel

scepticOfCheltenham wrote: »

We have just received a quote from SolarEssence for £5.8k for a 4kW system. It is the only quote we have had so far that details the equipment they are proposing and that gives a proper financial work up. Certainly beats the Big Green Co, who are asking £13k with no list of parts and a system (cost) prediction sheet that did not add up.

Care to expand on the kit they've offered as it may still be a little overpriced?


As for BGC, you'd be surprised how many fall for the spiel they and many others throw out.

scepticOfCheltenham

Kit they are offering is: 16 250W ECO-250M60 from EcoFuture and GoodWe GW 3600-UK inverter. 10 year warranty on inverter and panels.

The quote is the only one I have had which is broken down into separate items, with a price for each item.

One thing that amuses / confuses me is the warranties offered on panels, which are a 10 year manufacturer's warranty, but also a performance guarantee of 80% after 25 years. Surely if a panel fails completely after 20 years, it will have failed the performance guarantee as well...

theboylard

scepticOfCheltenham wrote: »

Kit they are offering is: 16 250W ECO-250M60 from EcoFuture and GoodWe GW 3600-UK inverter. 10 year warranty on inverter and panels.

The quote is the only one I have had which is broken down into separate items, with a price for each item.

One thing that amuses / confuses me is the warranties offered on panels, which are a 10 year manufacturer's warranty, but also a performance guarantee of 80% after 25 years. Surely if a panel fails completely after 20 years, it will have failed the performance guarantee as well...

I've got BoB (black on black) EcoFuture panels and they seem fine?
The inverter looks quite interesting - the UK site needs updating and the product link pages appear to go nowhere?!

However, Ecomaster in Norfolk have some more info.
Might be worth a look at their 4kw fully installed system - £5534.55 ecomaster site and choose 4kw from the dropdown menu.

scepticOfCheltenham

Looking at the contact info on their websites, solaressence and ecomaster appear to be the same company.

theboylard

scepticOfCheltenham wrote: »

Looking at the contact info on their websites, solaressence and ecomaster appear to be the same company.

Tell them you want a discount, and they can lose the voltage optimiser too!