New to Solar PV and getting quotes

mparter

Waiting on my Tesla Model 3 being delivered and decided I would look into getting Solar PV installed. I wouldn't be doing this on the basis of ROI but more along the lines of cheaper fuel for the car and saving house running costs.

I've done some research but don't have any particular allegiance to any brands. My house has a south-west facing roof (226°) with a dormer and is based just north of Edinburgh. One guy that came out reckoned I would be able to fit a 4 - high 4 kW array of panels. Another guy that came out basically wanted me to tell him what I wanted and the third asked for some photographs of my roof and sent me a quote based on that!

1. I was initially looking for a Solar PV setup with a battery. I'm now thinking, do I need a battery? As mentioned above, I'm looking at getting this installed to save money and fuel my car. I'm not too bothered about how long it takes to recoup the cost of install.
2. There's a chance the left hand-side of the panel array may be slightly shaded by the dormer during the later part of the day. Do I need optimisers?
3. Am I better just getting a Solar PV installed for now and adding a battery on in the future?

I'm struggling to get anyone to actually give me a quote at the minute. The only one that has, hasn't even visited. Are they basically looking for me to tell them what I want? Panels, inverters, etc. Whereas I'm looking for them to come and tell me what I need, so maybe there's an impasse there.

As you can see from above, I'm kinda unsure at this stage what approach I should go for. Solar PV with battery or without but with the option of adding one later. Should I get a list together of items and ask for quotes for supply and install rather than relying on them figuring it out?

I guess I'm just looking for a bit of guidance from a "seasoned solar PV veteran". Not sure if it matters but I'm planning to take advantage of the Scottish EST interest free loan which I believe is £5k for solar PV and £6k for battery.

Martyn1981

Hiya, got some general bits and bobs, but to warn you in advance, nothing definitive, sorry.

First things first, congrats on the TM3, I've got one and couldn't be happier.

Jumping straight in with prices, I'd suggest roughly £1k/kWp for about 4kWp, and if you haggle and perhaps get lucky, somewhere under £1k/kWp as you get into the 5kWp+ range. But there's another soul on here, been trying his damndest to get reasonable quotes for sometime, with no luck.

Still price related, there's no rush (unless that solar loan has time limitations), so take your time, chat on here, and don't pay too much.

PV for BEV charging is soooooooo great, but of course the BEV needs to be home when the PV is generating. If you granny charge at ~2.2kW, then hopefully the PV can cover all or most of that for many hours, and at a charge rate or around 8miles/hr you can be driving on sunshine, which I still think is mindblowing.

SW orientation is excellent, obviously you won't generate much in the early morning, and annual gen may be down 5-10% v's due south, but generating in the afternoon and early evening can help to displace a lot of household demand at times that are harder to avoid or timeshift.

Do you need optimisers/SolarEdge system, hard to say. If it's just a small amount of shade, for a small amount of time, perhaps not. I have SolarEdge on both my systems, and it's utterly brilliant at doing what it says on the tin, but if you don't need it, then it'll  probably add £500+ to the price, maybe even a grand, so it's a tough call.

I don't have a battery, but lots on here do. They really know what they are talking about, but my overall impression from reading what they say (and understanding little) is that it's great fun, but possibly not economic yet. So it may be a case of doing it, if you can spare the cash, to help maximise the usage of the PV, but it may not save you anything.


Not wishing to seem rude, nor pedantic, but I wasn't sure what this meant:

One guy that came out reckoned I would be able to fit a 4 - high 4 kW array of panels.

and having a rough idea of what you can, or hope to, install is really useful for giving advice. Do you know how many panels may fit, typically now expect to get panels of 350Wp+ each, so for instance 10 panels would be somewhere north of 3.5kWp (3,500Wp).

mparter

Martyn1981 said:

Not wishing to seem rude, nor pedantic, but I wasn't sure what this meant:

One guy that came out reckoned I would be able to fit a 4 - high 4 kW array of panels.

and having a rough idea of what you can, or hope to, install is really useful for giving advice. Do you know how many panels may fit, typically now expect to get panels of 350Wp+ each, so for instance 10 panels would be somewhere north of 3.5kWp (3,500Wp).

He did say how many panels but I can't recall the amount. I'm still waiting on his quote to be sure. He said that he reckoned with the amount of panels, it would yield between 4 and 5 kW.

Martyn1981 said:

PV for BEV charging is soooooooo great, but of course the BEV needs to be home when the PV is generating. If you granny charge at ~2.2kW, then hopefully the PV can cover all or most of that for many hours, and at a charge rate or around 8miles/hr you can be driving on sunshine, which I still think is mindblowing.

I forgot to mention, I already have a HyperVolt EV charger installed so will be using that to charge the M3.

mparter

The one quote I have had so far was around £4600. This was for a 4Kw system using JA Mono 340W panels, Solis 3.6 inverter, installation and all the related electrical work and installation.

Martyn1981

mparter said:

The one quote I have had so far was around £4600. This was for a 4Kw system using JA Mono 340W panels, Solis 3.6 inverter, installation and all the related electrical work and installation.

That's actually a good start. If 4kWp(ish) then that suggests 12 panels, so if you get them to come down a few hundred pounds, and up the panels to 370Wp (pretty common), just as an example, then approx 4.44kWp for £4,400, and you're already in the 'pretty damn good' ballpark.

Just to say, don't be surprised if a 3.68kW inverter is offered, as that size meets regs, before you need to ask permission to go bigger, and for the UK climate, would work well with 4 to 4.5kWp of panels.

Spies

It's the wrong time of the year to be getting quotes I've found as they're actually pretty busy installing systems. 

Solarchaser

Hi and welcome, nice to see a burger on these forums, and you may see me in my blue tm3 as I leave weegie land for burger ville a few times a week with work.

Is the tm3 likely to be at home during the day? If the answer is yes, then no point in doing batteries as the Tesla will sup up your free (solar) leccy, but if you are away during the day, then solar will be on when you are not there, and so depending on your electric usage it may be worthwhile. 
As in, if you use 6000kwh a year or more, I think batteries work, if you are only using 3500kwh a year, they will really struggle to pay you back within 15 years.

If the Tesla is at home, you may find that a zappi charger will suit you better as it works with solar.

mparter

Solarchaser said:

Hi and welcome, nice to see a burger on these forums, and you may see me in my blue tm3 as I leave weegie land for burger ville a few times a week with work.

Is the tm3 likely to be at home during the day? If the answer is yes, then no point in doing batteries as the Tesla will sup up your free (solar) leccy, but if you are away during the day, then solar will be on when you are not there, and so depending on your electric usage it may be worthwhile. 
As in, if you use 6000kwh a year or more, I think batteries work, if you are only using 3500kwh a year, they will really struggle to pay you back within 15 years.

If the Tesla is at home, you may find that a zappi charger will suit you better as it works with solar.

Thanks!

My usage for the last year was around 6500kWh. But I’ve been working from home in that time. I’m supposed to be heading back to the office in a month or so, so the Tesla will be at work for 3 days a week.

Looking back at bills pre-COVID, it looks like it’ll drop back down to around 4500kWh per year.

The HyperVolt charger also works with solar.

I’ll be collecting my M3 from Glasgow as the Edinburgh centre no longer does collections. So a nice wee drive back to the east coast will give me some time to get acquainted with the car!

Solarchaser

At work 3 days means potentially at home 4 days, so I think the solar could be a good thing, though it should be said the Edinburgh chargers are still free to use for the moment.

I've not heard of hypervolt, I'm not impressed with their website... or maybe its not impressed with my phone,  but the blurb sounds good, and it's good to see an alternative to the zappi, which seems to have ruled the solar charging for years now.

I dealt with Callan in the Glasgow office, and he was top notch for me.

I hope you enjoy your new toy, I absolutely love mine

mparter

Solarchaser said:

At work 3 days means potentially at home 4 days, so I think the solar could be a good thing, though it should be said the Edinburgh chargers are still free to use for the moment.

I've not heard of hypervolt, I'm not impressed with their website... or maybe its not impressed with my phone,  but the blurb sounds good, and it's good to see an alternative to the zappi, which seems to have ruled the solar charging for years now.

I dealt with Callan in the Glasgow office, and he was top notch for me.

I hope you enjoy your new toy, I absolutely love mine

Yeah the website doesn't seem to work great on my phone either but is okay on a bigger screen. Their support so far has been top notch (had a couple of install issues). Has built-in PEN fault detection and is "powered" by a Raspberry Pi so should be fairly updateable longer-term.

Just had my delivery text today so collection from Glasgow on the 7th September, the countdown begins

mparter

Finally got a quote through today. This is for a 12 x JA 380W panels, Huawei 5kw inverter and Huawei 10kWh battery for just under £11k. Anybody have any experience of the Huawei kit? Does the price seem reasonable?