Help - Advice needed on solar PV quote

Yeti1980

Hi
I am looking to get a solar pv system installed on the roof of my house and have received my first quote. Whilst I await quotes from another couple of installers I would be immensely grateful if I could get your opinion on the equipment and price in the first quote.

Just as a bit of background the roof is pitched at around 30 degrees and is East - West facing, the quote is just for panels on the East facing roof as this is completely unshaded although I will be going back to ask for a second quote to add a few panels on the West facing roof. These additional panels will only be on the top half of the roof as the bottom half of the roof becomes shaded by a large oak tree later in the day.

Components:
14x Jinko maxim integrated 300w high efficiency panels (total 4.20 kWp),
Schletter roof mounting system,
Solis MPPT inverter
Solic 2000 for diversion of power to immersion heater,
Landis gyr solar generation meter single phase.

Quote includes supply of components, EPC cert, installation, MPC Cert and commissioning. The system comes with 25 yr performance warranty on Solar Panels, 10 year product warranty on the inverter and labour & parts has a 5 year warranty.
So, drum roll, the quote is £4,620 inc 5%VAT.

Many thanks in advance

Martyn1981

Hiya and welcome. Without wanting to mislead you, or persuade you, my immediate response is that that seems like a good package and price.

I'd definitely explore the West option too, as it won't impact the rest of the kit, you should be fine with the same, or similar inverter as both orientations won't peak at the same time, so always cheaper to get as much PV in one go, rather than to add.

Struggling even to suggest any tweeks, perhaps ask about higher power panels, perhaps 330Wp etc, but the cost per Wp does start to rise somewhere north of 300Wp, so do the maths and see what you think.

Keep chatting and updating, I bet you have a 100 questions, and we probably have a 1,000 answers for you.

Mart.

1961Nick

Yeti1980 wrote: »

Hi
I am looking to get a solar pv system installed on the roof of my house and have received my first quote. Whilst I await quotes from another couple of installers I would be immensely grateful if I could get your opinion on the equipment and price in the first quote.

Just as a bit of background the roof is pitched at around 30 degrees and is East - West facing, the quote is just for panels on the East facing roof as this is completely unshaded although I will be going back to ask for a second quote to add a few panels on the West facing roof. These additional panels will only be on the top half of the roof as the bottom half of the roof becomes shaded by a large oak tree later in the day.

Components:
14x Jinko maxim integrated 300w high efficiency panels (total 4.20 kWp),
Schletter roof mounting system,
Solis MPPT inverter
Solic 2000 for diversion of power to immersion heater,
Landis gyr solar generation meter single phase.

Quote includes supply of components, EPC cert, installation, MPC Cert and commissioning. The system comes with 25 yr performance warranty on Solar Panels, 10 year product warranty on the inverter and labour & parts has a 5 year warranty.
So, drum roll, the quote is £4,620 inc 5%VAT.

Many thanks in advance

That seems to be a very reasonable price.

Splitting the panels between the East & West roofs would be better as it would extend the generating day.

pinnks

Given the move towards electric cars you might want to talk to whichever installer you chose about using the Eddi diverter rather than the Solic 2000. My reason for suggesting this is that the Eddi can talk to the Zappi from the same firm (myenergi.com). This means you can intelligently divert to immersion heater and car when the time comes. I think the firm also has an app that can act as a monitoring device too so you can see generation, usage and diversion at any point.

I have no idea of the cost difference but installation should be the same as these things are just intelligent switches...

Yeti1980

Martyn1981 wrote: »

Hiya and welcome. Without wanting to mislead you, or persuade you, my immediate response is that that seems like a good package and price.

I'd definitely explore the West option too, as it won't impact the rest of the kit, you should be fine with the same, or similar inverter as both orientations won't peak at the same time, so always cheaper to get as much PV in one go, rather than to add.

Struggling even to suggest any tweeks, perhaps ask about higher power panels, perhaps 330Wp etc, but the cost per Wp does start to rise somewhere north of 300Wp, so do the maths and see what you think.

Keep chatting and updating, I bet you have a 100 questions, and we probably have a 1,000 answers for you.

Mart.

Thanks for the speedy response.
Having seen various sites that suggest the cost of installing a 4kWp system would be around £5-6k or more I was pleasantly surprised by the quote and wondered if they were using particularly cheap (low quality) equipment which I take from your response I was wrong to assume.

David (Yeti).

JKenH

Yes, as others have said, the price looks fine. All I would say is check your roof orientation very carefully. If it is exactly E-W then spreading the panels across both roofs is a good idea but anything facing slightly north will be at a disadvantage. The orientation of my house is 15* off the cardinal points and the ENE roof seriously underperforms the WSW roof. If there is any way you can get some panels facing south it would be well worth a bit of effort/extra expense.
As an example over the year to date my East roof has generated 1.97 MWh and my West roof 2.62 MWh which equates to 547kWh/ kwp on my East roof and 623 kWh/ kwp on the West. A house nearby where the roof orientation is at 90* to mine has generated 818 kWh/kwp. I would suggest that you check out Mart’s excellent PV FAQ thread to check the PV that you might anticipate from your system.

Good luck.

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

Hexane

Yeti1980 wrote: »

Having seen various sites that suggest the cost of installing a 4kWp system would be around £5-6k or more I was pleasantly surprised by the quote and wondered if they were using particularly cheap (low quality) equipment which I take from your response I was wrong to assume.

No, these parts are fine. My inverter is a Solis, and mounting system from Schletter, both are absolutely fine. Solis (Ginlong) are of course a Chinese firm and not exactly Rolls Royce in terms of quality, but absolutely fit for purpose. I'm not familiar with the Solic 2000, I know there are alternatives for power diversion. (You might want to check if it's one of the ones that has a fan, some people have found these too noisy depending on where they're fitted.) The prices in the £8000 to £12000 range that you sometimes see mentioned on this forum and elsewhere, are from companies that just like taking plenty of your money and need to pay a lot of enthusiastic salespeople and advertising to do so.

I would advise getting a single quote for a total system of whatever you're getting both east and west facing at the same time, because I think you could run both off a single inverter ("dual MPPT" with one string to each set of panels) which would work out cheaper than two separate inverters. A complicating factor is that with both sets of panels together, your potential peak output could be over the 4kw "limit" and therefore potentially require permission from your Distribution Network Operator (DNO). It's worth checking that your installer is familiar with this process and willing to handle it; or alternatively limit the output by either using an export limiter or only getting a 4kw inverter.

I wouldn't worry too much about one of the orientations having "a bit of north" ... my east facing panels have that and it doesn't limit generation too much (partly because I have a deliberately over-sized system anyway). Now that you don't get paid FiT for generation, the advantages of south-facing panels are less substantial; and in terms of using the power that you generate, east+west orientation means more power at the potentially higher usage times of morning and early evening.

JKenH

Hexane wrote: »

Now that you don't get paid FiT for generation, the advantages of south-facing panels are less substantial; and in terms of using the power that you generate, east+west orientation means more power at the potentially higher usage times of morning and early evening.

That is true, particularly in summer. In winter I am not, though, generating enough to heat my hot water tanks and run the ASHPs -that’s when I would like some south facing panels.

I also have Solis inverters.

pinnks

I would recommend filling as many roof areas as possible ranging from east to west. This would allow you to max out on kW generation from sun up to sun down rather than having nothing for part of the day and then a load at another time.

My original system is on a broadly west-facing roof and until the sun eases round past south I generate a couple of hundred watts from "borrowed" light. As soon as the panels come into direct sunlight the generation leaps to 3+kW. I spent ages worrying about the probable impact of the shadow from my chimney, only to realise that it is irrelevant because it is gone before the sun hits the panels directly.

For this reason I added the second system on my south-facing roof. I now get up to about 1.5kW from about 9:30 meaning that I can boil a 1kW kettle. Come midday I can generate up to 5kW, meaning a lot goes back to the grid in summer unless we are running the washing machine and making the tea at the same time...

If money is more an issue than space, you could consider spreading less kWp over more roof directions, rather than placing the whole lot on one roof...

Hth

Hexane

If you're not planning any other monitoring, it's also worth asking the installer if the quote includes the Solis "Plug in data logging Wi-fi stick". This is a USB device that plugs into your inverter and communicates over Wifi with your internet router and thence back to Ginlong's servers. This allows you to check generation and other statistics of your system in near-realtime, and also view historical data. (It won't tell you how much you're using or exporting.) Some installers include this in the price, otherwise it is about £60.

Reed_Richards

The greatest demand for electricity is between the hours of 4 pm and 7 pm. If you pay for your electricity on an "agile" tariff then that is when it is most expensive. So those are the hours when your solar electricity is potentially most valuable. On this basis then west-facing panels may be the best.