System:
You would probably be better off having three seperate 3.3 kW systems, one on each phase.
Installer :
You should ask around and see some previous installs and get other customer feedback.
Do not use anyone using you as an inspection project ...we have removed two of these as appalling!
Use an established registered electrician not a new ECO start up company as after the PV bubble bursts your registered electrician will still be trading and maintaining his relationships with his long established customer base. Also most registered electricians will know about three phase.
You can find your nearest installer here:
The Microgeneration Certification Scheme
MCS PV registration has been around since April 2010.
We had our second inspection last week which was the end of our first PV year with over 60 installations. We had three minor non conformances - all paperwork related and all cleared on the day. This was three non coms for three technologies!
Find out how many projects your installers have done and how long they have been doing it. Dont be fooled by a flash website, ask for contact details of customers.
As an example we have a new PV expert started near us but they have only done the directors home and had two of our installation photos on their website until our solicitor wrote to them.
Modules:
We wouldn`t install any of the makes you mention.
IMO Sharp are poor and have delivery issues and Welsh fields full of returns which does not inspire a lot of confidence.
Try to get hold of the OKO test report which case studied 17 modules.
Kioto, Romag and some Chinese products are IMO only fit for lining a skip. They are however a lot cheaper.
For efficiency Sanyo is the market leader.
SANYO :: Solar :: Product Comparison
SANYO Component Europe GmbH - Sanyo Solar Photovoltaics-Europe: Home - Higher efficiency
For product strength which may be an issue on a community hall roof I would use Schott modules.
basically you get what you pay for, inverters from Germany, Holland and Austria are far better than the others and will still be around to honour the warranties.
Common sense says that not all of these start up PV equipment manufacturers in China will still be around in 25 years.
use the internet ...research is everything .
Good luck
Some good info here :
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