How much will my system earn?

[Josh Ekins]

Hello all, I've had a chap come round to talk about getting some panels on the roof before the tariff changes in Jan. I've signed up and am using the cooling off period to consider if I can afford it.

He's planned to put 10 mono panels on the roof (he said the mono panels produce more than the polys), it's only a few degrees off south and we're in Bristol, which is sunnier than most places in the country.

The calculations were done using minimum, guaranteed projections. He's guaranteed us a £600 per year return. That's £311 from the feed in tariff, £60 export and £229 "energy used" (which I assume means savings on our energy bill).

Some of the numbers he gave us are 30* inclination, 10 mono panels, 30* from due south, it's a 2.65kw system x 942 "kwh/kwp (kk) from table" x 1.00 shade factor = 2496 output kwh/year

The loan repayments are about £100pm.

So £600/12 = is £50pm

Which leaves us with a short fall of £50pm.

However, he also told us that these figures are a guaranteed minimum, that in reality the panels will produce considerably more than that. He also said that the calculation is based on poly panels, not the monos which we'll be getting. So can anyone give me an idea based on their own experiences of how much money the panels will likely produce? Our energy bill saving I suppose is a constant at £229, but how much would the current £60 export and £311 feed in likely be in reality? Not using the minimum statistics and using mono panels?

Sorry for the newbie questions, I'm very grateful for your help.

 

[telectrix]

i'm no expert, but those figures seem in the right ballpark. i'd be more concerned about the total cost of the system , over what period the finance is and what apr is the loan.

 

[Gavin A]

how much is that loan for? seems rather a lot for a 2.5kWp system assuming it's over at least a 5 year period that'd be £6k repayments.

some systems will perform a little better than predictions, but only by 5-10% or so average, so not by enough to get anywhere close to covering the loan payments. The energy savings on site look to be quite high too, I'd suggest you look closely at the assumptions made to produce that figure and see if they seem right - if you're a high daytime energy user they might be, but if you're out at work most days then probably not.

 

[sean_ork]

Also ask him exactly who will be providing the guarantee for the minimum income he has quoted - that just sounds like salesman speak,unless they've done a deal with an underwriter who will guarantee how much sunshine your roof will be getting for the next 25 years.

 

[TedM]

The figure for 2496 kWh/yr is the right ball-park for a 2.65 kW system. But for that to save you £229 a year off your current electricity bill looks to be a stretch.

Say you are paying 13p/kWh on your bill - that means a reduction of 1761 kWh in a year is required from a system that is only producing 2496 kWh. That's 70% and rather unlikely. 50%, coming to £162 saving, is more probable - especially as you make no mention of an Immersun, or similar hot water immersion diverter, being included. If you are home all day (especially all summer) and can arrange to use the power when the sun is shining then it might just work.

 

[Josh Ekins]

I am home in the day, so the savings shouldn't be too far off the mark... but if it's unlikely those panels will generate much more than he said then I shall cancel. He said the minimum payments are guaranteed and that they are liable if we don't generate that amount, but a £50 short fall on the loan repayments is too much for me at the moment.

The system is £6500 for 10 monocrystalline panels installed... the loan is something like 9% APR.

 

[sean_ork]

Cancel it immediately !

 

[Josh Ekins]

Cancel it immediately !

Why'd you say that Sean?

The only thing is the tariff changes at the end of the year.

 

[Somecamel]

£6500 is way over for a 2.65kW system. We charge that for a 3.99kW system with a Solar Edge Inverter.

If you're in Bristol, I'm sure there's a local installer on here that can help spec up a proper system for you.

If funds are an issue, might be better to take out a loan yourself.

I've run a quick quote through for a 2.85kW system using 10 JA Solar 285W Panels with a Solar Edge Inverter and it's coming in at £5533.23 so yes I'd cancel the above immediately.

What kind of boiler do you have? Do you have an Hot Water Cylinder with an Immersion element on it?

It's unlikely at this stage the 'Big' Feed in tariff cut will happen at the end of the year and the normal digression will happen to the tariff taking it from 12.47p to 12.03p which will make a minimal impact on the feed in tariff payments.

Don't rush this before the end of December. Any decent installer should really be stacked out until then.

EDIT:- I didn't include any access costs in my price and I'm not touting, you're too far away from me

 

[sean_ork]

Unless it's a very very difficult install that's an awful lot of money for such a small system - shop around, get a few more quotes - see if the bank will afford you a loan.

 

[Josh Ekins]

Thanks very much for your help guys, what would the access costs be? It should be a standard install.

How long do you think the tariff will stay above 12p for?

Unfortunately we recently had our immersion heater replaced with a combi on the green deal.

 

[Somecamel]

The big cut is coming, it's when that we're waiting for.

Best information at the moment is Feb 11th but this is just rumour.

 

[whinmoor]

If you have limited roofspace, you could consider more powerful panels from LG or BenQ.

 

[solarfred]

Will you get correct EPC?
What inflation rate is being applied to the rate of return calculation? (this has a big influence on the "savings").
I am not sure there is significant difference anymore between Poly and Mono so why use this as an excuse it is just a sales gimmick?