Poor Solar PV Installation ??? Expert Help Needed

[Bucks]

Hi guys,

I am new to the forum & am hoping for a bit of help & advice on the issue described below, before I get in touch with the installer.

Sorry but if you bare with me I will spread the situation over 6 posts, then add a few photos (I can't add photos until I have made 6 posts)

 

[Bucks]

We have just had a 3.92kw solar pv system installed on our SW facing roofs, 12 panels on the main roof which is two storey & 4 panels on our dining room roof which is one storey and is shaded by the main house in the morning.

The panels are Sharp NUR245J5 & inverter is a Fronius IG TL 3.6

 

[Bucks]

I am now concerned that the 4 panels on the dining room roof that are shaded in the morning will be affecting the efficiency of the 12 panels on the main roof,
Sorry I don't know all the technical jargon but as far as I know all the panels are wired together in one string.
Before the installation I asked about the shading issue & the installer said shading wasent an issue but he could wire the 4 on the dining roof in a separate string, but when they came to install the system his colleague said something on the lines of the four panels couldn't be wired separately as there wouldn't be enough power for the inverter and wiring them all together would be fine as the panels have diodes & mentioned something about the christmas tree light scenario.

over the last six days since installation we have generated a total of 18.7kw, but to be fair we have had hardly any sun.

 

[Bucks]

The installer is MCS approved & also a member of REAL

 

[Bucks]

Also someone has pointed out that I have shading issues on the upper roof from the boiler flue, soil pipe & ariel.

 

[Bucks]

Looking through a few of the other threads on this forum other alarm bells are ringing now about the state of the roof membrane, at first I thought this was collateral damage & couldn't be helped, but now I'm not so sure, this all a bit annoying as the whole top roof & membrane was brand new two years ago.

 

[Bucks]

 

[Bucks]

These images of the tears are just a few of many

 

[SolarCity]

Before the installation I asked about the shading issue & the installer said shading wasent an issue but he could wire the 4 on the dining roof in a separate string

Not with the Fronius IG TL 36, he couldn't. You'd need an inverter with dual MPP tracking to do what you are suggesting and you'd need one which had a voltage range low enough to accept a voltage that the panels would produce (without looking too much into it, I'd say the Power One range is a good bet)

but when they came to install the system his colleague said something on the lines of the four panels couldn't be wired separately as there wouldn't be enough power for the inverter and wiring them all together would be fine as the panels have diodes & mentioned something about the christmas tree light scenario. .

The reason they couldn't be wired seperately is due to the poor inverter choice and nothing else. Inverters with one MPP tracker can still have more than one string but they must be strings with an equal number of modules.

The Fronius IG TL 36 can have two strings connected to it but it is unlikely - this is because it cannot cope with higher amperages. This is one of the reasons why the IG TL 36 is generally only suitable for unshaded situations.

 

[Noshocks]

The fronius can be wired as one string as it has a high input voltage, and the other guy is right four modules couldent go on a single string, so it does look like its a single string, however shading is shading and not ideal, the bypass diodes arent going to solve the issue.
Have you got any pictures?

Have just seen the pictures, waste stack should have been sorted, this is a school boy error, as said the PVI-3.6 inverter would have been a better choice.

 

[SolarCity]

The aerials look like the will create shading judging by the fact that you are south west facing. The vent stack will be having a very significant amount of shading. The fact that the panels have been installed like that is, frankly, an utter joke.

All of the damage to the felt membrance is unnecessary and very, very bad workmanship.

 

[SolarCity]

Ask the installer for his opinion. Mention some of the points brought up on this forum and see what he says. Have you paid him yet?

 

[Bucks]

That is why I thought I would try & get some advice on here first before I get in touch with the installer
I have just paid him 20% deposit, I got the invoice for the balance today.

 

[SolarCity]

Not sure where you stand with the poor system design (after all, it's just my opinion)

I'd definitely get them to sort out the vent stack and sort out the weatherproofing on the felt. You ordered an MCS quality installation and shouldn't pay until you get one.

 

[SolarCity]

It is difficult to see how much shading the lower roof area is getting. If it is significant then I'd ask the installer to suggest an alternative inverter.

By my sums, the Sharp 245w panels are a little low on the voltage for the 4-panel string. However, the Power One inverters can be configured to fire at lower voltages so this might be an option (never actually tried it myself)

 

[Bucks]

The lower roof area is shaded from the main house until about midday
Other people have told me that with them being wired into the same string as the other 12 panels, the efficiancy of the 12 top pannels would be greatly reduced.

 

[JD6400]

I would go with what Biggs is saying !
As for the vent pipe we had two neighbouring houses only about three weeks ago with two on each roof , after a quick enquiry with a building a contractor we work closely with on other projects and a double check of what they said with our domestic roofers just to make sure , half hour latter we have four tile vents at about £40 each and the job is looking good !
I may be barking up the wrong tree but do you live in Bucks more specifically Steeple Claydon , your house design does look very similar to some in that area ?

 

[JD6400]

Just looked at the pictures again , now i may be wrong but the block of four are clamped on the their short side , not sure about the 245's but i know that used to void the warranty on the 235's ?

 

[nbown]

you can cut down the soil stack and fit a 4" air emittance valve, that would stop the shading of the top roof. i took mine out completely and removed to boxing in in the bathroom.

Just for reference and it may not help as i'm in Essex. I had my install done on Saturday (not running until Sunday, low light levels) 3.92Kw (all panels on the roof), SSW facing. Fronius IG-tl 3.6 and have produced 43KWh.

Question, what's the darkening on the panels, it appears in the area where the junction box could be on the panels, i'm not saying it's right or wrong, i was just trying to work it out.

 

[Bucks]

I may be barking up the wrong tree but do you live in Bucks more specifically Steeple Claydon , your house design does look very similar to some in that area ?

No I live in North Yorkshire

Question, what's the darkening on the panels, it appears in the area where the junction box could be on the panels, i'm not saying it's right or wrong, i was just trying to work it out.

I dont know what it is