photovoltaic panels. How to choose

[merv]

My original post was june of last year.

Still no useful answers.

[Green Aura]

Hi fellas and welcome to Ish.

Unfortunately we don't allow advertising until you've been active for a while so I've removed them for the time being.

Sorry merv, you're question seems to have stumped us! Shame because I'd like to know how to choose the best system - it's so difficult for the lay person.

[Renewable]

I'm seriously thinking about installing a 4KW system. How are the efficiencies of the different panels measured ? What units should I be looking at when talking to the salesperson ? Any pertinent questions to pose ?
Any help appreciated
Merv

questions regarding your proposed system :-
1. Is it grid connected or standalone ?
2. If roof mounted , how much unshaded south facing roof space is available ?
3. What is the condition of the electrical installation in your home , do you have an RCD ? , is the earthing to current regs ?
4. Do you live in an area of oustanding natural beauty , do you need planning permission ?
5. If roof mounted what is the condition of your roof and roof timbers like ?

things to consider ...
a) If a company sends out a salesmen he is likely to be commission hungry so common sense says the job is going to be dearer. Do not sign anything on the day whatever the promises are .... you should receive a full MCS quotation with solar prediction before you do anything and you have a seven day cooling off period if you want to change your mind.
b) What you want is a few MCS surveys from smaller companies (no salesmen, no fancy eco shops etc ) where the actual installer is going to do the survey.
c) MCS surveys are FREE so go to the MCS search for an installer and find your nearest ones. Do not pay for an MCS survey.
http://www.microgenerationcertification ... Installers
d) Ask to speak to some of the previous customers and maybe go see some installs. recommendations are better than leaflet drops !
e) Do not use anyone offering a cheap non MCS install which they want to use for their MCS inspection project , we have removed two so far as both failed to meet the requirements and installers had vanished.
f) Do some reasearch ...Ideal Solar Ringwood, Hants is a national installer, featured on watchdog and in which report, so why do people still employ them ?
try the bad solar company website to see who to avoid . (http://www.heatmyhome.co.uk/solar-panels/?p=275) (http://www.realassurance.org.uk/news)
g) Ask Real the customers protection group for renewables if they have any knowledge of complaints about a member ( http://www.realassurance.org.uk/)
h) Ask to see your installers qualifications, apprentiship deeds, MCS certificates, insurances,real membershipetc etc get as much info as much as you can and do not be pressured into anything. Ensure you know who you are getting information from and that they can prove they are qualified to give it.

Make sure you buy the best quality of equipment available and try to stick to companies you have heard of .
modules by Sanyo, Schott, Schuco,Mitsubishi, Sharp
inverters by Mastervolt, Fronius , SMA
are just some of the better known names as these companies will still be around in the future . Some of the better inverters even have warranties extendable to 20 years.
If you buy cheap, "rushed onto the market to fill a void" , equipment you may regret it later.

Aesthetics are important to most customers , for example your proposed 4kW system is going to need :-
17 x Sanyo 240 watt ( 16 would look better, 4 x 4 or 8 x 2 but would only be 3.8kW) but these are over £600 each . (10,200) or
24 x at 170 watt which is going to take up a much larger roof area but cost around £400 each. (£9600)

A maximum budget "sort of price" is £5000 a kW so your 4kW system should be cheaper than 20K , including VAT at 5% . Obviously if your home needs massive electrical improvement that will cost as well .
As a guide our dearest ever project, so far, is 16.5 K for 3.5kW including VAT but included extensive electrical works to the home , 18 way board with RCBO to each circuit , earthing, equipotential bonding, sorting out a few existing faults etc and also about 4 hrs drive from home and staying away in b/b.

Hope this helps.

[merv]

Margo,

thanks for your very informative reply. Still didn't answer a couple of my quesions : what units are usefull to know/understand when comparing systems/panel types and talking to salespeople ? (furlongs per fortnight don't help)

second, typically (not theoretically or based on manufacturer's literature) how much can I expect to generate from a 2Kw system, facing south, unshaded, 35° roof slope, south of england ? I need this to calculate ROI at 100% feed-in. I can understand 2Kw crest but how often does that happen ?

Lastly, I would very srongly recommend solar water heating, not necessarily integrated with central heating. We have ours fore 3 years now and ROI is already 80%+

tnaks again

Merv

[Renewable]

Using an MCS approved solar prediction calculator gives you this result.
(The MCS predictions are IMO massively reduced but I believe this is to reduce the possibility of litigation.)

assume South facing, 35 degree roof, unshaded, Brighton, 2KW Poly system.

Feed in 1702 kW per year . minimum
Feed in tariff £702.93 . minimum

2 kW system costing £10K max outlay .
Return on investment
25 years at £702.93 minimum is £ 17,573.25 .
plus export bonus at £100 minimum over 25 years
plus reduced import costs of up to 40% .

As an alternative guide :-
My own system at home is West facing and 2.2kW and had a feed in payment MCS prediction of £538 per year . It was signed into fits on 25th May 2010. Our pre PV annual spend on imported electricity was averaged out to £80 a month. I have taken generation and import figures from day one. Our import has dropped to £29 June and £39 July.
We have generated 610 units up to 1/8/10 which is £251.93 with export bonus of £9.15.
We have also saved £80 + £80 - £29- £39 which is an additional £92 swing .
I had my first cheque for £116.84 for the period up to 30th June 2010. You get paid every three months. So my next cheque is due for July/Aug/Sept in early October.

So in two months we are nearly at the 50% figure for the MCS prediction . Although there is less sun hours in the winter it is also cooler so sytem will perform better and I fully expect to overtake the MCS predicted figure way before xmas.

If you want a copy of this information or see my system in Poole, Dorset or a free information pack just let me know.
nick

[merv]

Margo, or Nick, either way I could kiss you. Exactly what I was looking for

thanks


Merv

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(a free info pack would be useful. Please send to merv.newmanxyN°4@gmail.com (forget the bit in code, that's just to confuse searchbots))
m