Have some Solar Panel quotes - was looking for advice

markin

It must be worth trying some larger companies that will travel? Or has the China panel shortage started to affect prices uk wide?

ispookie666

Looks like a reasonable quote.

Definitely yes to littering your roof with panels. As others have said your predominant N facing will be reducing less during the summer months and pretty much nothing during the darker months. 

My panels are split over 4 roofs - it's a very new system and hoping for it to hit the expected target of 5.2MW/yr from installed capacity of 6.6KWp @£1.6/KW.   I do have Enphase micro inverters 

flyinggoose

Exiled_Tyke said:

I have to agree with Martyn.

 If the other two roofs don't have serious shading issues then you can spare the additional cost of SolarEdge by going with a two string system and just stick to the two roofs.  So I think the additional costs of going onto the NW may be significant and not worth it or indeed if you crunch the numbers may make sense for the additional generation.  

Could you get quote 3 to upgrade the panels? Then I'd be more tempted.

I did ask about upgrading the panels but they said higher rated panels would mean they would be able to fit less of them on as they would be bigger in physical size meaning a smaller system overall, obviously the other company disagrees there, so i don't know which ones correct at this point, i did look at the dimensions myself for both panels and the higher rated Trina panels were slightly bigger (about 10cm in length).

The roofs facing south may have slight shading in the latter part of the day, i'll have to get outside at certain points in the day and check, i'm more leaning towards just the two roofs at this point because i've also realised that with the 5kWp system over three roofs thats 1.66kWp per roof, whereas the 4.29kWp system over two roofs would give me 2.14kWp per roof, so going over three roofs would mean less output from the two roofs which are best positioned for the panels, and the 6.63kWp for £8983 would give slightly more at 2.21kWp per roof but the price is quite high, so i'm not sure its worth it going over three roofs now after seeing it all this way, i might be better off saving the extra money for a battery in a few years time.

I've also read in a couple of places that installers should be checking the roof from the outside and inside the loft and making sure the roofs can take the weight of the panels, is this correct? I've not had any installers telling me they would need to do this inspection first.

2nd_time_buyer

I've also read in a couple of places that installers should be checking the roof from the outside and inside the loft and making sure the roofs can take the weight of the panels, is this correct? I've not had any installers telling me they would need to do this inspection first.

Yes, that is a requirement of MCS approval. In practice, few do. Those that do will probably just check that the roof  is of standard construction, not sagging, and in good conditions. They are not structural engineers.

I did ask about upgrading the panels but they said higher rated panels would mean they would be able to fit less of them on as they would be bigger in physical size meaning a smaller system overall, 

Yes, you are right that higher-powered panels tend to be bigger as the efficiencies are similar. An exception is the SunPower Maxeon panels which have higher efficiency and much higher cost. Jinko Tiger range have slightly higher efficiency and are a similar price to the Trinas and worth a look. They do them in two different sized/power-output in the same range. This means you might be able to work out a combination that fits well. 

The other issues where the guidance is a bit grey is the distance the panels are situated from the roof edges. This is dependent on the mounting system. Generally, the minimum is 0.2 m but 0.3 m is often recommended. If you are not in a very windy site going down to the minimum 0.2 m could be considered.

Finally, you might want to check the accuracy of the roof dimensions. They will be going from Google maps. This has some inherent accuracy, particularly if the photo is not taken from directly above. Also make sure they are assuming the right roof slope when projecting the roof area. The easiest way to do this, without going on to the roof, is to count the tiles (and look up tile dimensions and overlap).

Aussie_Tips

Flyinggoose, 

First question I'd ask is why no battery 🤔. Second question - you don't mention your daily consumption so how do you know your system will meet your needs? 

I started by looking at what my electricity consumption was, converted that into how much solar or battery I needed, and then used that to go to suppliers and have an informed conversion rather than get a bunch of sales patter. It also meant I could compare quotes fairly as a slightly under sized quote may save me money but still cover the majority of my needs.

In terms of how much energy is produced, I've made some broad assumptions based upon my reading. Have a read of this, it explains in straight forward term how I worked out my usage, turned that into solar & battery spec, as well as giving some pointers on how to select a supplier. It also covers the assumptions I've made about how much will be produced.

Hope it helps

https://pghintsandtips.blogspot.com/p/my-contribution-to-net-zero.html?m=1

QrizB

PGammage said:

Flyinggoose, 

First question I'd ask is why no battery 🤔.

Probably because the financial case for batteries remains marginal.

flyinggoose

PGammage said:

Flyinggoose, 

First question I'd ask is why no battery 🤔. Second question - you don't mention your daily consumption so how do you know your system will meet your needs? 

I started by looking at what my electricity consumption was, converted that into how much solar or battery I needed, and then used that to go to suppliers and have an informed conversion rather than get a bunch of sales patter. It also meant I could compare quotes fairly as a slightly under sized quote may save me money but still cover the majority of my needs.

In terms of how much energy is produced, I've made some broad assumptions based upon my reading. Have a read of this, it explains in straight forward term how I worked out my usage, turned that into solar & battery spec, as well as giving some pointers on how to select a supplier. It also covers the assumptions I've made about how much will be produced.

Hope it helps

Funny you mention that, initially i wrote a battery off due to roi issues and thought i'd wait a few years for battery prices to come down but with whats been happening these past few days i've been looking into some of the Octopus tarrifs and have a few ideas about how i'd make use of a battery if i was to have one installed, i'll have to run a few calculations though and of course those tarrifs could change/dissapear so will have to think carefully about which way i go about it.

Spies

IMO you need enough panels to at least cover base load when its cloudy and rubbish as, the majority of the time in winter, that's the weather you get.

flyinggoose

Good point, i did read the post you linked to, interesting info, thanks.

In the meantime i've almost decided to go with a Tesla Powerwall, £9000 installed on top of the solar pv cost, i've done the calculations, i'll recoup 50-70% of the costs, maybe, in the next ten years but i'll be happy with that.

Screwdriva

We invested in a LG panel + Solar Edge system and couldn't be happier. I've experienced mixed reviews of the Chinese component manufacturers, especially around after sale service, so would strongly caution against them. 

This was a quote given to a neighbour recently for a 4kW system incase it helps you?

Equipment;

10 x 400w Hyundai panels, 25 year warranty to 86.2% efficiency and a 25 year product warranty

10 x Solar Edge optimizers fitted to each panel making the panels smart panels. 20 year warranty.

  1 x Solar Edge 3600w HD Wave inverter system w/ 20 year warranty

  1 x All cable run’s isolators and fitting’s 

  1 x Micro generation meter

  1 x System Wi Fi monitor  

  1 x System registration

  1 x Access Equipment

  1 x MCS and G98 Certificates 

 All service and maintenance under the terms of the warranty.

Fully fitted price of £5,650.00