Solar Power systems

udo's picture
udo started the topic in Sunday, 8 Jun 2014 at 7:50am

Solar power .
set up costs
off grid
grid connected
buy back tariffs
lifespan
maintenance
your story

wellymon's picture
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wellymon Sunday, 22 Jun 2014 at 5:20pm

Yeah Udo, as you can see a lot of the trees are 35-40m high and the ones closest to the North side are right on the boundary, which is only 2m from the house. I have fallen these same 40m trees in my yard before to clear stuff away from the house as well for firewood. I have had no complaints from the neighbours as they are cool, but I think it is against council regulations. Hey what do ya do...?
If I go for solar panels, for the long run of electricity bills soaring double in the 10 years, which has happened in the past 10 years..? Yeah I will cut at least the top third of these big boys off. The ridge of the top roof is about 17m high, thats where the fall restraint attachment point comes in handy :) I don't think I would survive.
Also what youve said down against a bank in the yard where captures heaps of sun all day, will look into
that. Nice one

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udo Sunday, 22 Jun 2014 at 6:20pm

On ground set up also keeps the solar panels operating temp much lower........which is a good thing and the ease of panel cleaning for full efficiency, I see lots of solar hot water and power panels very dirty, dirty enough to reduce there output by up to 25%.

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southey Sunday, 22 Jun 2014 at 11:13pm

Welly ,
It's late and I've had a fair w/end .....
Couple of questions for now , I'll have a good look at tomorrow night , especially after I do some regional regulations homework .
Is that Nth indication , true Nth ?!? ( you may have already answered that , if so I apologise )
Do you get any relief from the heat via sea breezes during summer .!?! And if so what direction is it from
( NE , SE ) ???? I noticed the main range ridge line looks roughly to your SSW . ???
You have a light coloured roof so I would say That rooftop wouldn't necessarily be more heat effected than ground mount out of the wind !!! ( as udo pointed out ) .
Remember that somewhere in a clearing , but still surrounded by trees / ridge lines etc will heat up more because of at the end of the day you want sun exposure , but you also want air flow ... The house roof itself will create a natural "chimney " airflow effect ... And down in gullies or lower ground surrounded by hills and large trees , often there is less airflow .
I'll need to check if your Allowed any sort of tilt system ( ie if your in a cyclone rating zone which doesn't allow for it , and if so will require and extroadinary amount of extra support . ) in which case you could tilt two three rows to face nth on the expansive east roof . Extra incentive that routine cleaning wouldn't lead to risking the 17m side ....
Alternatively to get that Nth roof pitch cleared of shadow .
You might need a string attached to an arrow ( alternatively a strong arm and a decent rock ' with string tied to it ) , a bigger rope and a solid four wheel drive .... May happen to be in your area , the day before a strong blow ....
Winters good for this , and leave the snapped evidence still attached to " Altered trees " .... Council no issue ... Perhaps , "refresh" your neighbours prior ... " bloody dam , orthographic down winds " can be near tornado-ish , Especially when recollecting to council stooge !!!! ;-) maybe take one or two branches away from the area you want to support evidence .... ( ps plant one or two more to keep sheepy happy ) :))
Can you estimate for us distance from coast as crow flys ....

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ethereal Monday, 23 Jun 2014 at 10:14am

Any thoughts on LiPo or capacitor banks to smooth the peaks outside Solar hours ??

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wellymon Wednesday, 25 Jun 2014 at 3:59pm

Southey..! Ridge line points at 340 degrees, just off North.
We are Cyclone dependant as regards to strapping things to the roof.
We are 300m above sea level so its always 3-4 degrees cooler up here than the flat lands especially in summer. But winter is different sometimes being a couple of degrees warmer than down in the valley.
We are situated off the ridge that cops the full brunt of SE and East winds during cyclonic summer periods, which gives as a quite favourable situation when it comes to full on brunt from the winds:), The winds tend to go right over the house, giving us remorse. I have witnessed this before about 5 years ago when we had a low develop not far off the coast and produced 125-130 km/ph winds. Sat on my verandah lee to the wind looking west and watched a few big trees snap before our eyes...? pretty full on.

I hear you about putting rows along the ridge line each side, as so to tilt... North.
What kind of angles do they have to be tilted.... 20 degrees plus....? We can do this as I think this is a great option..?

No need to worry about ol Welly chopping trees down as I have in the past and will in the future, I have good communicable neighbours..

In your own opinion could you refer a good panel...? As have looked up all the great links to your suggestion with inverters.
Cheers Champ.
Much appreciated.
Welly

udo's picture
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udo Wednesday, 25 Jun 2014 at 4:14pm

Anyone know if you need to inform your insurance company when you have a solar system installed ?
Large hail would surely damage the panels.........I wonder if they would pay out if...eg; a very large KW system was fitted and all panels were badly damaged and needed full replacement..........would they pay ?

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donweather Wednesday, 25 Jun 2014 at 5:03pm

Udo, I certainly haven't informed them and I've just gone through half a dozen new quotes for home and contents insurance and not one insurance company asked if I had solar panels. I assume it would be included in your "contents" policy, so you'd just have to make sure your contents amount on your policy is enough to cover the panels should you lose your entire house and contents in a fire. Otherwise if a hail storm came and smashed only your panels, then you would just claim these under you Contents amount.

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donweather Wednesday, 25 Jun 2014 at 5:29pm

Welly, with respect to the most efficient panels, you need to find out from each proposed solar panel installer which panel manufacturer and panel model # they use. You can then check here to see how efficient each panel from each installer is.

http://sroeco.com/solar/most-efficient-solar-panels

http://sroeco.com/solar/table/

But as per the article in the top link above, it's not always about the most efficient panels. it's about the most kW produced for the least money outlayed.

http://sroeco.com/solar/learn-solar/solar-panel-comparison/

That is, one installer may be offering you a cheaper system with slightly less efficient system (Tier 2 panels), whilst the other installer may be offering you a very expensive system with the most efficient panels (Tier 1). Do cost per recieved kW and you should then be able to determine the best value for money system offered and you'll usually find it's not a Tier 1 panel that gives you the best value for money (hence why most panel installers don't offer Tier 1 panels) as there's bugger all efficiency difference these days between Tier 1, 2 and 3 panels.

http://sroeco.com/solar/solar-panel-efficiency-tiers

Takes a lot of research believe me, as I did it for mine.

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wellymon Wednesday, 25 Jun 2014 at 7:03pm

Thanks heaps Don, great info champ.
I have opened my eyes up, regarding this whole system,as when I spend monies on it (which I honestly think is viable due to soaring electricity costs), I want a good system that will last and save us money in the long run.
I appreciated the input from all you guys here, thanks heaps ;)

Don what kind of system do you have...?

Udo you are on to it, as about 4-6 months ago we got the most full on hail up here, honestly champ I was at home and filmed it, late arvo and the hail was half to three quarter size of a golf ball....? Covered the whole back yard and looked like snow had fallen..?, dented the flashings on the skylights in the pictures of the latter,,,? , not the roofing tho...?

Hey it would smash the solar panels..? Any thoughts..?

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udo Wednesday, 25 Jun 2014 at 7:31pm

clickbait Welly ........Horizon solar.

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southey Wednesday, 25 Jun 2014 at 11:01pm

Welly , I'll go over your options , which probably amount to how much ( on your nth aspect ) you willing to lop completely and if not how often your willing to " trim " branches only . Opening the north aspect will also help you out on those cooler sunny / winters mornings - days , reducing any heating if at all needed .
( think this Sunday/Monday cold ) .

In short , a tilt system is viable in your area , just the mounts need more fixings . The other thing is whether your worried about esthetics or how obtrusive they look from the front of your house versus performance .

Sorry Don , I don't completely agree with you .
Firstly Tier 1 versus Tier 2 , has very little to do with efficiencies ( except for the fact that most established tier 1 companies , actually continually test for product efficencies and in general far greater QA ) hence your getting a greater guarantee that they will perform to that claimed efficiency and for longer . A good text of this , is pretend for a second that you were a company that had to borrow / or finance to install a large system .... Banks won't touch you unless you go with an established panel manufacturer .
Not only testing is far more rigorous but more often ( not just a one off batch , then pump out whatever afterwards ) , the tier system represents manufacture techniques , R&D , general capacity to meet warranty issues , and whether or not the company purely just assembles others materials or they genuinely control every process , from crystalline cell culturing right through to Smart logistics delivery and most importantly reliable backup ....
Again as I said before , it all depends on your expectancy of the systems output .

Sure , economically you can install a system that you can get a return on investment as short as 3-5 years . As opposed to say 7-10 years .... But how many times will you get additional returns after that . And in some cases , you'll run the risk of not even getting a return .
These systems should be minimum for most people around a 15-25 year investment ....
Toyota's don't outsell TATA's for no good reason . Generally speaking a car will be 3-4 times more of an outlay compared to a good solar system . Lately most people turn cars over between 5-10 years and generally will lose anywhere from a third to half of its value .
But with the advent of cars like the Outlander PHEV , a solid Solar system is going to replace the lions share of running expense .

The government rebate masks alot of the install costs . Trust me you don't want to have to pay for someone to come in , fault find , remove , redesign , replace and re commission your system .... Apart from the initial panel costs themselves ( hopefully you used a module manufacturer that will be around to honour its warranty and provide replacements modules free , let alone some labour component ) , the labour component of initial install is the next expensive item . And if it isn't , then your installer is cutting corners .

Anyway most good manufacturers actually have hail tests , and will cover any damage from hail up to a certain size . Having your panels tilted higher than 20 degrees above horizontal will help with deflect hail and small debri , if you are in a place that frequently has large hail you could always have a roll of shade cloth setup ready to drape over the tilted panel rows when and if there was a " hail warning " .
Lastly I've seen photos of panels mounted direct parallel to the roof of a house that pretty much got destroyed by Yasi in FNQ . The panels looked nearly untouched and I fact held that part of the roof together .... Not so certain the latest panels with 38mm frames as opposed to the old 50mm frames would hold as good .... But that's all driven by aesthetics and cost .... Not to mention architects and wankers pushing for the black ( mono ) panels to have black frames to make them look less obtrusive on dark tiled roofs .... Talk about heat gain ....

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donweather Thursday, 26 Jun 2014 at 9:00am

Welly, I have a 2.4kw (12 panels) system with a 3 kW inverter. I went with a reputable, long standing company for my installation as I wanted them to be around when the warranty is still alive. I chose Bradford Solar (same company as Bradford Batts). They use a Tier 1 Suntech panel for my install and a good quality Aurora Inverter.

Southey, I doubt very much whether a panel manufacturer would come back and replace your panels if damaged by hail. At the very least the panle manufacturer would expect your house and contents insurance to pick up this bill or the panel installer.....but hardly the manufacturer.....yes they will quote how strong their panels are but as to coming back to replace (under warranty) after a hail storm I wouldn't think so.

I just did a quick google search and found this warranty by an installer and they clearly DO NOT cover hail damage.

http://www.ingenero.com.au/sites/default/files/Ingenero%2010%20Warranty%...

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southey Thursday, 26 Jun 2014 at 2:24pm

Don ,

Nothing I'm saying in here is personal and neither what i say is being negative ....

Definitely it would be wise to actually go out of your way to let your insurance company know that you have installed x amount of PV modules on your roof etc etc ....... you will probably have to supply them a safety certificate and mayeb even a copy or your contract & warranty terms . Obviously if you have a small system , then the costs of insurance may outweigh the benefit .Generally i wouldn't expect your insurance company to charge you much more .

Australian Standards in which all panels are subject to , (to be eligible for the REC " rebate " ), have to pass a Hail test ..... equivalent to hail the size of golf balls hitting panels from directly 90 deg from horizontal .... considering most panels are tilted atleast 10 deg's but more likely 20 to meet manufacturers recomendations , and hoping that your brand didn't just produce one bullet proof / rolls royce set for testing ,
, then your talking literally hand of God stuff . ( note this ties in with the Tier 1 system of testing , and European tested components are far above this ....
You are quite within your rights to question a manufacturer as to their panels not standing up to these tests , obviously your insurance could cover these costs , but when proven at fault ... ( i know its hard to prove the size of hail ) they will / should replace like for like , materials and where complete failure is noted then you could claim a reasonable rate for labour incurred by your installer ..... ( we are talking a slight chance , in a major event , not unlike the risk of lightning in remote areas )
Obviously reputable installers will try to help you out , alot of the time the installer is not the same entity as the sales team . This is not the installers issue however , it needs to be followed back up the " sales " tree .... ie sales , distribution , wholesale , manufacturer .

Anyway , do you know what configuration the designer has gone for with your install ...
ie : - is it two strings of 6 panels , or one string of 12 .....
either way unless i knew these and a few more details , i see slight concern at its efficiency .... not something dangerous or whatever more getting bang for your buck ...

This ties in with what i first said about making sure the system is tailored to your install ...
I won't go on record to say whatever equipment is bad or this and that ....

Can i ask why you chose a Insulation company to install a technical / expensive electrical system . ??? ( i understand your reputable company ideal , and whole heartedly agree across the board , do you think they may even be in it for the right reasons ) ....

I often question , and am confirmed that many " solar " entrepeneurs , rolled from the failed insulation scheme into the SRES / REC scheme .... Basicly already knowing the finer details of the Labour / Greens designed " Teet sucking - Gravy train " of spending & handouts ....

Both Aurora ( power one ) [ now owned by swiss electrical giant ABB ] , and Suntech are no doubt good quality equipment . Its often let down a little by not optimal design ...

As for company origins , i presume you know Suntech's history ...

In short , The chinese founder studies and lives in Aust. applies for funding grant way back in the late 90's early 00's . Doesn't work out , moves back to china and goes hard for high end module efficiency . On the back of this becomes the largest manufacturer of high quality , general mass production , above average efficient panels ..... acquires large Japanese PV company , etc , etc ....
Unfortunately wheels fall off in 2012-13 .... Bought out by another giant Chinese corporation ....

Anyway like many PV module companies they have a roller coaster past .
They did / do produce quality panels , i just wonder if they actually have an Australian office Even when dealing with the most professional Chinese outfits , when push comes to shove do you expect a chinese company to follow international law ? But don't stress , this will be " Bradfords " problem if anything was to go wrong .... not that you would expect it with materials , install labour hard to say ?

Anyway i digress , feel free to get back to me with finer details of install like welly has . i can evaluate the installed whole of system efficiency ...

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wellymon Thursday, 26 Jun 2014 at 2:37pm

Thats not nice Don. How can these solar panel companies mention religion....? haha

"Any “acts of God”, eg lightning, hail, storm"......?

Thanks again for the info fellas, great stuff again.

Nice call about the shade cloth Southey, I hear ya, which is very simple, we just have to be there when shit goes down;). As with aesthetics, I'm not really worried as I'm not the ponzi materialist kind of bloke:) I'm more involved with performance.....

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southey Thursday, 26 Jun 2014 at 2:50pm

Welly ,

Just a second hand pool cover reeler would do it .... attach it to the roof or facia ( if you have one ) , then it could double as a shade to say the wesetrn side of your newly " unshadowed " house ....

If your not home ..... well , then hopefully your panels passed " the test " .
I do know some dudes that control their evacuated tube solar HWS with a " roller shutter " ....

i'm sure a macgyver type rig worker like yourself could set some gadget up to pull the shade sail ( remotely via phone ) over said panels in an emerg. ;-)

udo's picture
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udo Thursday, 26 Jun 2014 at 2:54pm

Sheepskin cover

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wellymon Thursday, 26 Jun 2014 at 2:55pm

Yeah Southey just read your post above, it came thru whilst typing..haha.

Great post there champ, you know your stuff for sure and thats why I got interested and it all makes a lot of sense.
I'm beginning to get a little picture here about Chinese manufactured panels and the likes... No offense to anyone ;)

In your own opinion Southey what are the best panels manufactured at the moment ie, bang for bang.

You also mentioned Lighting strikes does this fuck the whole system up or is there a cut off point, as regards to electricity and the invertors etc, if I'm on the right page length....?
Cheers

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wellymon Thursday, 26 Jun 2014 at 2:58pm
southey wrote:

Welly ,

Just a second hand pool cover reeler would do it .... attach it to the roof or facia ( if you have one ) , then it could double as a shade to say the wesetrn side of your newly " unshadowed " house ....

If your not home ..... well , then hopefully your panels passed " the test " .
I do know some dudes that control their evacuated tube solar HWS with a " roller shutter " ....

i'm sure a macgyver type rig worker like yourself could set some gadget up to pull the shade sail ( remotely via phone ) over said panels in an emerg. ;-)

Classic was already thinking of a set up where I could tilt the panels, manually from inside at different parts of the day ;) Also a hail cover, sheepskin one..:)

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southey Thursday, 26 Jun 2014 at 3:09pm

Nah , don't stress about lightning ... its probably only an issue where there are no trees and the terrain is flat . My point was you can't avoid lightning strikes , its not predictable so i wouldn't stress out about these things too much .

I mainly use Q-Cells & Kyocera panels . Not to say that i wouldn't use others , but I'm not a mass installer and don't advertise at all . I'm also busy with "other work " so I'm currently trying to build a base to eventually get involved in the commercial market . Suntech , Phono amongst other Chinese manufacturers are good value , its just not what i'm interested in .
I don't want to start installing $5 parts with $50 labour .... Long term its not a sound business model . Unfortunately many industries are heading that way .

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southey Thursday, 26 Jun 2014 at 3:21pm

I woudln't personally entertain that type of tracking system in domestic , perhaps " Off Grid " .
Moving parts in extreme winds is never a good idea .....

Although that being said , this survived " cyclonic " :)))) winds the other day ....

" http://www.hiltonmanufacturing.com.au/category/solar/ " .

its location is well exposed there to strong winds . During its construction i had a few detailed convo's with their designer .... ( Hiltons designed and installed this themselves , for themselves as a showpiece of which they will advertise and sell similar equipment when the market is ready for it ) .....

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fitzroy-21 Thursday, 26 Jun 2014 at 3:48pm

Hey Southey, loving all this info, really appreciate you passing on all your knowledge here.

What is your opinion on Trina Honey panels or Canadian? I have been discussing with a few installers and they have recommended these panel. The research I have done on either panels look pretty sound with good reviews for Trina in Aust hot conditions. Aurora and SMA inverters (which you have mentioned in previous posts) as a choice also, with both seeming OK to me.

Cheers

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udo Thursday, 26 Jun 2014 at 4:42pm

Gotta like that clip- knobs in suits on a factory roof ,people have left the purpose built viewing platform.... and not a safety rail or hardhat in sight.
Not a real good look for Hilton manufacturing.

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donweather Thursday, 26 Jun 2014 at 4:36pm

Southey, certainly appreciate your response mate. I chose Bradford because I knew they'd be around in 7-15 years when things would start to go wrong and hence I can chase them directly for warranty claims rather than having to chase the manufacturers directly. I did sufficient research between half a dozen different solar companies and decided that Bradford provided quality panels and inverters for a reasonable price (ie they weren't the cheapest) and piece of mind they'd be going the distance in the future to chase up warranty claims.

And to be honest, alot of "Solar" companies subbie out their work whereas I questioned Bradford and was told their installs were done by their direct staff/labour. Again I felt more comfortable that Bradford (my installation company) had more control over their direct staff/labour than subbies.

As for the orientation of the panels for maximum efficiency, unfortunately, the roof that I wanted them installed on already had a solar hot water panel and hence we had to work around it and the TV attenna (birds sitting on the antenna then shit all over your panels!!!), hence we have very little roof space on that side of the house left to "optimise" the panel efficiency install.

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donweather Thursday, 26 Jun 2014 at 4:41pm

One also has to be careful with the installers, particularly if you have a colourbond/tin roof. The aluminimum panel brackets need to be isolated from the colourbond/tin/steel roof, otherwise dissimilar metals corrosion can occur. Again, Bradford were all over this when I asked them to provide details on their brackets and connections to a colourbond roof.

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wellymon Thursday, 26 Jun 2014 at 4:45pm
udo wrote:

Gotta like that clip- knobs in suits on a factory roof ,people have left the purpose built viewing platform.... and not a safety rail or hardhat in sight.
Not a real good look for Hilton manufacturing.

True udo;)

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udo Thursday, 26 Jun 2014 at 4:46pm

isolate the ali from the roofing iron, doesn't dripping water from ali to iron roof still have a dissimilar metals effect ?

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donweather Thursday, 26 Jun 2014 at 5:17pm
udo wrote:

isolate the ali from the roofing iron, doesn't dripping water from ali to iron roof still have a dissimilar metals effect ?

I highly doubt it to any great extent otherwise alot of structures around the place would be well and truly fecked!!! The water acts as an electrolyte passing between the two dissimilar metals, but only when the two dissimilar metals are in contact. But I'm not metalurgist!!!

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southey Thursday, 26 Jun 2014 at 5:16pm

udo ... don't stress mate .... there are full Aluminium walkways and on roofs of such low pitch , as long as you don't go within 3 M of the edge you don't need handrails .....
Besides we could all do without one or two " Journalists " ... , and this is Victoria ( the nanny state , I'm sure they had it under control ) ....

Fitzy ,
Trina's have a good rep , and so do Canadian ... ( it's just that i tend to lose faith in someone that continues to call themself one place when only their toenails are clipped there ..... )

Don , most bracketing / racking systems come standard with " Insulators " rubber to avoid dissimilar metals .
Hopefully the installer uses them , the other thing is all holes should be in the ridges of corrigations where possible , proper dektites are a must sealed corrigated conduit is good , mounting isolators on the edge of Panels bad ..... and don't let anyone use a " hole saw " anywhere near your roof . And if there is no other alternative then you better hope they clean up with a Magnet , broom then hose .

I've spent my entire working life , working on roofs ( mainly commercial ) , this is the critical thing about Solar .... Generally speaking apart from Air Cond/ Mechanical services electricians sparkys never used to do much work which will be fully exposed to weather . Its been a long , painful and sometimes expensive learning curve for most new comers .... You just don't want to be the person thats paying for their " Tuition " so to speak ....

Don , I'll add to that Isolator note ....
When really coastal and on low pitched corri roofs . I tend to use
40mm UV rated polyurethane feet between the Ali and colourbond or more importantly the bare Galvabold ( tin ) . Wet weather , salty air provide a good medium to pass electrolisis across seperations greater than 10mm . ( most manufacturers rubber insulators are only 5mm , if that ) . i learnt alot more about this on powerlines around Salt lakes in WA .
Do you know which way they wired the panels , two strings or one ?? How many ( i know Qld was reluctant to put them on the roof ) isolators do you have on the roof . And if not how many DC plugs do you have going into your inverter . ?
BTW with some maintenance , you can change that " would " to " could " in regards to things going wrong .

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donweather Thursday, 26 Jun 2014 at 5:20pm

"Do you know which way they wired the panels , two strings or one ?? How many ( i know Qld was reluctant to put them on the roof ) isolators do you have on the roof . And if not how many DC plugs do you have going into your inverter . ?"

Unfortunately Southey I can't answer those as I don't know.

And sounds like you're a very caring bloke when it comes to installs and isolating the dissimilar metals, which is a damn good thing. A couple of installers I spoke to knew very little about this issue!!!!

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southey Thursday, 26 Jun 2014 at 5:34pm

Don ...
In commercial especially new buildings the roof plumber have to give very long warranties on their new roofs , so they get VERY upset when and if someone fucks it up . I don't know how many plumbers you know , but like concreters they should not be fucked with .... Especially when we are talking millions to replace ...
All this works in my favour when the Commercial market takes off .....
Going back to domestic , a house gets fucked pretty quick when a the roof fails ... Up there ( pardon the pun ) with foundations ..... So saving $1000 on an install doesn't really weigh up when putting your bricks n mortar ( or in Morris's case - Underpass ) at risk ....
Don , just count the DC wires entering your inverter by plugs .

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wellymon Thursday, 26 Jun 2014 at 6:55pm

Awesome stuff Southey, yep I hear you about all those little things, which people forget about in the long run. 5mm, yeah you might as well put 10mm buffer in. Love it. It really does make sense. I'm all for that.

"( or in Morris's case - Underpass ) at risk ...."

I think hes fine as I only seen him yesterday after a long time, picking up his dirty undies and going to the laundromat ;)

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donweather Thursday, 26 Jun 2014 at 6:58pm

Southey I have a DC isolator array which has two cables going out of it and into the bottom of the inverter.

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old-dog Thursday, 26 Jun 2014 at 8:36pm

I got a 1.9kw (10 panels) system about 5 years ago, best thing I've ever done, haven't paid a cent for elec. since. (60cent Feed in tariff for 25 years) they currently owe me 300 bucks. Cheapest Chinee panels and inverter on the market, hasn't missed a beat. the system only cost 3k installed and has already paid for itself several times over. My panels still look brand new, no yellowing or snail trails like on some expensive well known brands, inverter is on West brick wall in full sun and has been through hail and 45degree heat waves. On a cool summers day I get over 14kw. even though the panels face almost due West. and its a good feeling when you're not home knowing that its all getting exported at 60c /kw.
These days with a tiny FIT for only 3 years you need a much bigger system just to break even, but it could still be worthwhile even with the much longer ROI. You really have to do your homework as some installers are cowboys and wouldn't have a clue, I spent ages on Whirlpool green-tech asking questions
before taking the plunge, like they say " If you aren't prepared to lose a grand deposit don't go solar "

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southey Thursday, 26 Jun 2014 at 11:42pm

Yes old dog .
Your not alone there ... I've been pointing all along to long term efficiency . I would say without knowing too much about your whereabouts that I'm presuming is somewhere close to Adelaide .
Not 100% sure on the average insolation ( peak sun hours daily average ) there , but can almost guarantee it's much higher than Southern Vic .
I have similar size systems running on 1.5 kW inverters performing just aswell . Yeah they cost $1000-$1500 more , but I can guarantee that they don't disconnect from the grid / turn off from over temp and also start up earlier and shut down later on cloudy days ..... All from a fair bit less average sunshine .
Do me a favour , next really hot cloudless day , check to see what time it shuts down from over temp .
I presume that it's JFY brand or whatever and I could be wrong and the designer could have genuinely matched the panels performance curve to the inverters . But generally speaking it's going to run as low 50-60 percent conversion on many full sun days .
Western mounted inverters can be "okay " especially if serving a eastern facing array . ( the inverter does it's hardest work in shade ). But on a western facing array , and worst still a house without eaves , the west wall in full sun on bricks pretty much will see it struggle to stay connected for more than two -three continous hours without turning off and on every 1/2 hour after . Especially in later afternoon days that turn partly cloudy but still high ambient temps .

Even the most basic inverters will have indication of when they are still connected to the grid .

Again power to you man , your a " paid power generator " as my uncle likes to declare with his 66 Cent FIT.
When it's paid for itself multiple times who cares . As for everyone else getting nothing or perhaps 8 cents FIT well these details maybe important ...
Cheers old mate .

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southey Friday, 27 Jun 2014 at 12:00am

Don ,
Without knowing your exact model number inverter or the internal wiring connection . You say two wires which I take to be two individual plugs into the bottom of your inverter ( ie : ONE string with the two lugs being Positive and Negative leads . Unless they have done some internal linkage ( if possible with that inverter ) . Then I'm pretty sure that the single string limitation of that inverter is 2kw . Whether or not that just means it's limited and stays producing at that level or it shuts down beyond that I can't be certain . Worst case scenario could be that it's shortening the life of the inverter or worst still doing it damage .
AnywaY kind of hard to diagnose from a keyboard . I tried !

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southey Friday, 27 Jun 2014 at 12:27am

Welly ,
I just use 40mm urethane blocks , because I've used them prior with gal unistrut .
And they are made direct by one of my Aust . Mounting Material suppliers .
I tried to show a link to them , but it's too hard . So you can view them at the bottom of the photo gallery section on this website . " www. Choosesolar.com.au "
They are flat ontop and the bottom matches the corrigation profile , so they maintain and even increase the strength of the roofing sheets . A definite bonus for tilt systems in cyclone regions . Only small problem , unless you buy them in large quantities they are a little exxy . But as I said coastal frontage they are invaluable .

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donweather Friday, 27 Jun 2014 at 7:46am

Thanks Southey I'll post up some pictures later of the connections into the inverter and model #. There is 4 plugs available for the DC in but they've only used 2 of them. If they've limited the inverter to 2kw then why does the inverter maximum daily readings on the inverter screen show over 2kW?

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donweather Friday, 27 Jun 2014 at 9:03am

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donweather Friday, 27 Jun 2014 at 10:33am

Hmmmmmm, Southey you might be right? Reading the paragraph in Section 3.3.5.1 (Pg 34 of the pdf link below) and then going to the table in Section 8.1 (Pg 93 of the pdf link below) it appears they may have only wired it up to take a maximum of 2kW....so does that mean every time my panels generate more than 2kW I'm damaging my inverter?

http://www.infiniteenergy.com.au/pdf/AuroraOutdoorUserManual.pdf

And again, if they have only set it up as 2kW, why then does my inverter display maximum daily kW readings above 2kW?

Should I contact Bradford and ask them these questions?

Edit: Ok now I am confused. Pg 33 of this pdf implies you can internal wire INT1 and INT2 in parallel? Could they have done this and hence my system may still be OK (ie not being damaged and generating more than 2kW)?

http://www.solarenergyproducts.com.au/files/PDF_uploads/Aurora_PVI-3.0_3...

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southey Friday, 27 Jun 2014 at 12:47pm

Don ,
Don't stress . I apologise for bringing this up . I presume they have done it right . I wasn't sure if the aurora did peak power logging (P Pk ) amongst many other measurements and thought that perhaps you were not as offay with it and potentially reading the E tod ( total daily power generated ) .
I'm sure they have done the internal link .
Again I apologize for that as unfortunately I was all setup to do the power one training , but the distributor that organised it for me last year went belly up (Redset ).

Atleast you and others know for possible issues that can happen . Again your due diligence will serve you well as it has already , those Aurora's are a good unit . As most reputable installers and suppliers use them .
The fact that ABB bought them out is only good news for you .!!
Many good units like that one won't ( shouldn't be damaged ) by reasonable over power thresholds , the most import at thing is that the arrays feed the inverters ( even in extreme cold and full sun ) still remain within the voltage and amperage thresholds .
Generally speaking most good units , will drive the receiving conversion away from the MPP to compensate and still output but at the designated limit .
So if your regularly seeing above 2.2kw peak values on good PV insolation days then I reckon your sweet .
The combined panel voltages do fall within the higher efficiency conversions of that inverter , and better still to make sure they will on high ambient days your panels are east of nth , so generating in lower ambient so on top of the bonus that your colourbond roof is of a lighter colour . So provided the inverter gets good shade then your system looks a good design . The string array you have does go near the " sweet spot of the inverter " , so in this case smaller array to inverter is not too bad .
Cheers man .

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donweather Friday, 27 Jun 2014 at 12:43pm

Thanks Southey, so because the inverter is displaying peak daily outputs over 2kW you're comfortable they've wired it up correctly?

Amazingly, for a 2.4kW system, my highest ever daily maximum output peak was 2.8kW? Go figure?

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southey Friday, 27 Jun 2014 at 1:08pm

Yeah , peaks are good . That just shows that the system is well setup in orientation , placement and inverter to panels compatability ??! .
At the end of the day , avg yearly yield compared to a similar system in your area is the ultimate guide . Your technical enough , I'm sure you could setup yourself on pvsys or pvyield sites . That creates a portal that others can view your generation to compare , and let's you like for like compare .
That and matching your consumption ( time of day ) load curve is important .
High peak reflects good + sorting of your panels, ( good panels have a 0-+5% of nameplate power rating ) ie on those cooler sunny days around midday your 200 watt panels may produce /deliver 210watts.
Not sure on the accuracy of 2.8 kW peak though ?!? From memory your panels may only be -/+ 3% anyway .?!?

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donweather Friday, 27 Jun 2014 at 1:30pm

Yeah I've only ever seen the 2.8kW figure once, most other times its around the 2.4kW-2.5kW.

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wellymon Friday, 27 Jun 2014 at 1:34pm

Yeah nice one Southey trying to gathher all this info, which is the beez kneez.
I noticed Don saying he has a "a 2.4kw (12 panels) system with a 3 kW inverter"
Back in the latter thread you were saying, correct me if I'm wrong about having a smaller invertor than the panel output....????? As to drive the inverter to its maximum use.
So 'Don' has 2.4kw panels combined with a 3 kW inverter....??????
I think I'm getting a little confused, but I'm sucking it in, which is great info ;)

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old-dog Friday, 27 Jun 2014 at 2:49pm

@Southey, Yeah I'm South of Adel. on the mid coast. My inverter never shuts down due to heat, but it
generates about 5-10% less when it gets over about 35 deg. Its a transformerless 2kw. inverter with no fan and barely even feels warm on hot days. The only time it shuts down is when it gets dark. Two story house on top of hill so it's still producing a few hundred watts as the sun sinks into the sea in the West. Cheers.

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donweather Friday, 27 Jun 2014 at 3:12pm

Southey my inverter is on the south side of my house and it never gets direct sunlight on it. Bradford were very keen to put it in the garage (which gets very hot as our metal garage door faces NW) but I talked them out of that to put it in a very cool (no direct sunlight) south facing location.

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southey Monday, 11 Aug 2014 at 3:14pm

Welly ,
You'll notice that I clarified that I thought it was better for coastal locations ( 50k's from ocean ) anywhere from , about Coffs Harbour through to RAdelaide was good to " overdrive " your inverter .
And pretty much anywhere in Tassie along with Sthn Vic it really makes a difference .
Bare in mind that the further Sth you go in higher latitudal geographic regions , that the sun sits as low as 25 degrees latitude [ being degrees above the Northern horizon ] between 10 and 2 ... ( directly over head is 90 degrees latitude , so basically at noon on the tropic of capricorn on the summer solstice the suns latitude is directly over head ) Also the Azimuth is the degrees from true north that the sun sits in the sky . Anytime of year , near enough to noon the sun will be at 0 deg azimuth and around the summer solstice the sun can rise and set as low down as 125 deg azimuth .
When it comes to sun in the Sthn Hem everywhere south of the Tropic of Capricorn has the sun stay in the northern sky at all times throughout the year ( I reckon everyone involved in this thread knows all this but I'll explain for the " lurkers " ) ..
Anyway obviously (unless you argue with BB in the climate thread ) the earth is a sphere , and above this sphere we have the atmosphere that follows the curvature of the earth , anyway the sun averages about 1380watts per square meter outside the atmosphere . On a clear day ' generally speak ' ( moisture / water vapour / humidity will effect this , think contrails ) , well an hour or either side of solar noon the average on a clear day is 1000 watts per square meter . Basically the suns rays have to travel through roughly 1.5 times the length of atmosphere when the suns lower in the sky . Be it east or west ( early or late in the day )[everywhere] or in places like here in Vic it stays lower the sky to the north so basically down in these higher geographic reional latitudes regardless of no cloud cover , you struggle to get any where near your peak rating for two - four months of the year .
Anyway I think I'll give it a rest for a while , I'm probably boring or confusing you guys ... ( bad habit of mine )
Old Dog ,
Topology ( type of components used in the DC-AC transfer ) effects the units reliability long term .
Basically galvanically isolated transformer inverters rely on less electronics . Hence a little more robust , but they contain more heavy/bulky metals , hence weigh more and cost more .... Are you certain of it not "decoupling " , do you have monitoring which gives you a graph of daily output ?! At very least you should have LED's on the unit that indicate if it's " generating " . When I say switch off , I don't mean completely shut down . Just minimal to no output , sometimes they won't cut out at all because they are setup to run on the extreme upper voltage only limit . The problem with that is that they are then vulnerable to over voltage during extreme cool days when a fog quickly dissapares around noon , then full overhead sun hits cool panels ....

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udo Friday, 27 Jun 2014 at 6:55pm

Southey, you just done my head in ....wish you posted that before my evening billys, phew..

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wellymon Friday, 27 Jun 2014 at 7:19pm

Classic Southey.....
And no ....
I can't argue at all, when it comes to literature ;)
Love it.............

"Anyway obviously (unless you argue with BB in the climate thread ) the earth is a sphere , and above this sphere we have the atmosphere that follows the curvature of the earth , anyway the sun averages about 1380watts per square meter outside the atmosphere . On a clear day ' generally speak ' ( moisture / water vapour / humidity will effect this , think contrails ) , well an hour or either side of solar noon the average on a clear day is 1000 watts per square meter . Basically the suns rays have to travel through roughly 1.5 times the length of atmosphere when the suns lower in the sky . "
.
I think you know more Southey ;)
Respect

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wellymon Friday, 27 Jun 2014 at 7:29pm

Southey...!!!! as there are people here that like this info, especially coming from a surfer who surfs some good shit ;)

Quote Southey "Anyway I think I'll give it a rest for a while , I'm probably boring or confusing you guys ... ( bad habit of mine )"

Great info, way more that anyone here can give us.
Thanks heaps.