Help please - 2 parallel South South East facing roofs

[jdeep]

Cheers Solar City. I am really tempted by the Sanyo. They seem to be the "best" panel and can all be placed on one roof at the back of the house.

Only one additional problem in my mind is that the company offering the Sanyo have only obtained their MCS certification in Nov last year. The started the company up in July 2011 and previously worked for other companies for years before. They are in REAL and MCS accredited and seem very genuine.
My head tells me to play safe with the Suntech unless the Sanyo is a much much better deal but am I worrying about nothing if they are MCS and in REAL.

 

[SolarCity]

The key is to talk to their past customers and go and take a look at their work.

I've seen work from MCS firms that have been registered for ages that is utterly shocking so it's not necessarily a good measure of quality.

 

[Earthstore]

On the main roof are they leaving a decent border around the edge, it should be 500mm, or are they squeezing as many panels on as possible?
Why not go for the Suntech and have two inverters, you may find you would get more out of your system that way.
Hope this helps.

 

[jdeep]

SloarCity - I now have 3 previous customers telephone numbers to chat with tomorrow
Earthstore - We estimate 300mm from Ridge to first and the same gap from bottom panel to guttering
Following earlier advice on here I looked at power one pvi 3.6 inverter, dual tracker to run 2 uneven strings (11 + 5) or (10 + 6) or to deal with shading issues.
I believe reducing the start up voltage on MPPT 2 helps.
Happy to consider 2 smaller inverters. Do their combined ratings need to be under 4kW. Will they still be guaranteed not to produce more than 16A

 

[SolarCity]

Something to consider when going for two inverters is that the efficiency of the smaller inverters will probably be lower than if you went for a single inverter. Transformerless inverters are a rare beast when you go below 2kWp.

I'm preparing to be proven wrong with this, but I don't consider a low start up voltage to be such a big issue. It certainly helps with designing a system but you really don't need much light to get a pretty high voltage so I don't see it increasing yield much, if at all.

 

[jdeep]

Hi SolarCity and others, First sunny weekend day for ages up here, Spent most of it on garage roof watching shadows and on SunCalc website. How sad am I.
I am almost certain to to go 4kW 16 X 250 Suntech (11 + 5 split). With power one pvi 3.6 inverter. I will have no shadow on 11 but some shadow from chimney on 5 from mid afternoon. Shadow should be reduced when sun higher in sky. Need to act quickly for March deadline but look to take down chimney during summer. Unless the installers tell me differently I will leave start up voltage at default. The company originally suggested 2982 kWh on a 3.5 kWp system. Hope for around 3200 for 4 kWp.
Thanks for all your help