Looking to get solar panels

Raggs_2

I'm sure there's been thousands of threads like these, but I guess each one is also unique.
Just starting to look into solar. Heard back from Silvercrest energy, who are also solartherm UK from what I can gather.

They've quoted a 3.7KW system, made up of 10x 370W panels, on an almost south facing roof. There is a chimney on the roof, but plenty of space around it, and hoping with just 10 panels to avoid major shading issues. We also have an almost west (slight southerly) facing roof that could be used instead with no issue from shading.

So 3.7 system, with a 5.8wkh solax (i believe) battery, and netting to stop pigeons etc getting underneath. Installation etc, quoted at £10145. Seems a bit high to me, but the battery is large. 25 year guarantee on the panels, with a 30 year performance guarantee. I've asked for information on exactly which panels, battery etc this is for. 

They also push signing up to Social Energy. I'm not sure if this is a requirement or just recommendation, so I've asked for clarification. They sell it in terms of trading electricity helping balance the national grid and earning credits, but I've been reading some stories about customers not getting anything, finding it hard to get their smart meters installed etc, so I've asked for more details there. I think I'd rather just use the electricity ourselves, as we do have an electric car (albeit a tiny Zoe, but can probably top up the car daily). Not sure if the credits from trading would offset the extra we will have to pay in standing charge and per unit.

We're on the isle of wight, so plenty of sun relative to much of the UK.

We're looking to do it because we obviously have quite high electricity usage with the electric car, and I work from home. It's also to be greener. Also been looking into going for finance on it, rather than paying cash. Of course overall the cost will be higher with the interest, but it fits better with our current plans, debt is not a concern.

So advice? Suggestions? Recommendations of companies to contact/avoid etc?

ABrass

Batteries are borderline on breaking even for most people. I'd ask for a quote without it for comparison purposes. It also looks expensive, £4-5,000 is a good price for a 4kW system.

Raggs_2

I work from home, so there's basically a computer running for most of the day, with regular cups of coffee throughout, most the week will be 2+ people at home during the day, and 3 adults and a child at home in general. With the car as well I was thinking we can pretty much guarantee making full use of every bit of generated power, hence the battery. Though I guess such a large battery may not be required since we'd not actually get to a point of having that much stored.

ASavvyBuyer

With a 3.7kW system it is very unlikely you would have much spare power to charge an EV for the majority of the year. Most of the time, the system will not be producing 3.7kW. Most EV's usually need a minimum of 1.4kW to start charging and at that level of charging it is not very efficient.

Also, suggest that you get at least 3 quotes to compare prices.

Raggs_2

Just had another company call, although unfortunately they don't cover the isle of wight, quoting £6250 for 3.8kw and a 5kwh battery. Which looks like a very good price to me. Shame they can't actually help!

EDIT - I realise the panels couldn't solely charge the car, but I meant more using the electricity in the battery along with mains, to charge it, to ensure we use everything we produce.

michaels

WE charge our leaf at 2,2kw just set it to charge for the portion of the day when pv output is likely to be above this level.  AFAIK you can choose any export tariff provider although I think there may only be a couple, probably worth looking at Octopus.
https://octopus.energy/outgoing/

Our panels are W facing and if you have a variable export tariff the generation (most from 11-6) is probably worth more than the export from s facing panels even though output is about 10% lower.  I also can't see the value in batteries at this time.  Our 4kwp panels 3.68 invertor was installed 5 years ago for 4600.

Petriix

Run a mile from anyone suggesting that batteries will ever break even for all but the most extreme usage profiles. You might do alright with a 4kWp system if you can get it for around the £4,000 mark. Do some simple maths to work it out and ignore their projections.

Start by looking at how many kWh of electricity you use in a typical year and then work out how much you can realistically shift to times when you are generating. In my house we average around 10kWh usage per day, 3500kWh per year. With our 3.42kWp solar PV system we are roughly able to halve this to 1750kWh which saves us around £220 per year off our bill. We both work from home and are often in during the day.

We also get a low feed-in-tariff of around 4.3p/kWh and deemed exports of 5.5p/kWh on 50% of what we generate which adds up to around £250 per year (from 3500kWh generated). On the Smart Export Guarantee which has replaced the FIT, we would only get around £100.

On our purchase price of £4150 that's between 8 and 9 years for us to break even under the FIT. Under the SEG we would be looking at 13 years. You need to do your own sums, but don't assume that you will use more than 50% of what you generate, and base the savings on 12.5p/kWh. 

Raggs_2

So now in contact with a company that's offering 5.5KW and around 6KWH battery for £8k. Don't need a system that large, but if they can do something more appropriate at a more reasonable cost, that'll be encouraging. They also apparently fit a system around here in the last 2 weeks.

Exiled_Tyke

Raggs_2 said:

So now in contact with a company that's offering 5.5KW and around 6KWH battery for £8k. Don't need a system that large, but if they can do something more appropriate at a more reasonable cost, that'll be encouraging. They also apparently fit a system around here in the last 2 weeks.

Sounds better.  A few suggestions 

1. Put the details on here for us all to have a look over. 
2. The bigger the system the more of your winter electricity requirement will be produced by the system. There are plenty of days in winter where I barely get 1 kWh so I still import most of what I need.  (There have been a few days in the last week that have been equally bad) but today I shouldn't pay for any electricity so it's definitely a laundry day! )  So don't underestimate the benefits of a bigger system. Most on here would encourage you to go as big as you can afford (within reason) 
3. I presume you've thought of it already but can you go to see what they've installed and talk to the customer?  If they are as good as they sound then they really won't have a problem with this. They just have to ask their customer first. 

Raggs_2

Definitely planning on posting up here first, will ask them for information on what panels they're suggesting, which battery etc. And yes, I was planning on asking them to ask if their previous local customers are happy to talk to us.

Fair point on the larger system generating more over the winter.

Currently we live with my mum, have done for a couple of years, and it seems to be going OK, and no desperate urge to move out, but obviously we need to take into consideration the possibility of us moving out, and then it'll only be her left with the system and repayments. It'll be a numbers game as it often is. We'll work it out though.

Pile_o_stone

If I were buying panels now I'd buy the largest solar array I could afford (and fit on the roof) and not worry about batteries. You'll end up exporting a lot of energy in the summer months but you'll use it all in Winter and the shoulder months (and on rainy or overcast days), and these are the months where your electricity bill is at its highest.