Opinion on solar system.

[EEVblog]

I'm quite close to ordering a home solar system.
Definitely want a Sunny Boy SMA TL inverter even though more expensive.
But I know nothing about the solar panels.
One company has offered a 3KW system with SMA Sunny Boy 3000-21TL inverter and 12 x 250w Trina ‘Honey series’ poly panels for $4690 + meter install ($330-$400)
http://www.solarchoice.net.au/blog/wp-content/uploads/Trina-Honey-Solar-Panels-Spec-Sheet.pdf
A 2KW system is $3490 + meter.
Or a "premium" system of 12 x 250w LG mono X panels for $5190 + meter.
http://www.lg.com/us/commercial/monox-solar-panels

They are pushing the LG panels with this:

STOP PRESS: We have recently been appointed as an official preferred installer for LG solar modules. We regard the solar modules from LG to be superior to most modules on the market and are proud to be recognized as a premium installer and awarded official status by LG Electronics Australia. LG solar has zero debt which is a significant advantage for future warranty and support and this feature should not be underestimated (what is a 25 year warranty worth if the company stops trading?).
All warranties are held and supported by LG Australia with a 7 day helpline. LG also has some unique and innovative solar cell products and the newest module neon X is way ahead of the competition.

Another company with same inverter wants $5000 + meter for 12 x Suntech 250watt panels.

And another company with same inverter wants $4490 for 12 x ReneSola 250W Virtus2 JC250M-24/BBV-2

A real bottom dwelling cheap arse 3KW system with 12 x 250W Schutten Mono Crystalline Panels and Delta inverter is a low as $3299 (not $4299 as advertised)
http://www.eurosolar.com.au/solar-power-systems/systems-with-250w-solar-panels/3-0-kw-solar-system/
Using JFY inverter that goes to $3499

Panels will go on the WNW roof at 311 degrees.
Video of the late afternoon sun from 4:00pm to 6:28pm


Opinions?

[4to20Milliamps]

I've installed quite a few solar systems over the last ten years, the newer generation of solar panels are pretty robust, one thing to watch out for are the way the connections are made to the back, stress on the junction boxes causes a majority of failures.

A high quality panel that has good encapsulation and extra support will be more crack resistant:

http://www.kyocerasolar.com.au/assets/pdfs/we_are_in_the_details.pdf

http://www.kyocerasolar.com.au/australia/index.php

[mikes]

My opinion on the solar system is that Pluto really isn't a planet. 

[SeanB]

Good idea, just choose one or the other.  Monocrystalline panels are more efficient normally though in direct sun. Just choose panels that have the best efficiency, and the longest warranty.

[Lightages]

I would like to add that Kyocera panels, although not the cheapest, are really robust. I would not hesitate to buy more. For a time I needed my solar energy working and did not have the frame for the panels built yet. I place the panels on the ground and one day a strong wind picked one up and it flipped/flew and landed corner first into the panel next to it. Nothing but a bit of a scratch in the panel.

[NiHaoMike]

You might be able to save a lot by connecting the solar panels to the rackmount UPS through a MPPT controller and using the UPS as the inverter. Not all UPSes can do this when plugged in (many older rackmount units could), so to test, plug the UPS into a power meter, plug a load into the UPS, and try adding power right at the battery with a bench power supply to simulate the solar panels. If the input power drops significantly and the battery voltage stays at the float point (even when fully charged), you've got a great UPS to use as an inverter. The MPPT controller is pretty easy to build (it's just a DC/DC converter with a microcontroller) and would make a great open hardware project. (In the meantime, you could just get a close match between the panel MPPT voltage and the battery float voltage and just use a simple overvoltage disconnect and blocking diode.)

Assuming you do need to buy an inverter, Delta is a very good brand.

[4to20Milliamps]

Australia has a lot of good solar resources, this place a has bunch of different manufacturers and technologies set up for anyone to go have a look at:

http://www.dkasolarcentre.com.au/

http://www.dkasolarcentre.com.au/flash/processmap.html

[mtdoc]

Dave-

Solar panel efficiency is unimportant unless you have limited roof space or you are mounting on a tracker or a pole mount in which space is at a premium.  The efficiency of all modern, commercial solar panels are within a few percentage points - since you look to have a pretty large roof area to work with efficiency should not  be a deciding factor.

Similarly - all the large solar panel manufacturer's warranties are pretty similar these days - 10 yrs workmanship, 25 yrs performance with a derating for age.  It's true that many solar panel companies have gone belly up so the stability of the company for warranty purposes might be something to consider - but the truth is that solar panels rarely fail. In the rare case that their performance falls out of spec - this will likely show itself right away.

Mono versus Poly crystalline - also a non issue. Mono panels are generally slightly more efficient (non issue - see above) but any other differences (sunny vs cloudy performance) is minimal.

Bottom line is that solar panels have become a commodity product and all the large (mostly Chinese) manufacturers produce similar quality panels - despite the marketing hype.  There surely are some cut rate - poor quality panels being made somewhere but it's unlikely any professional installer is going to use them.  Trina solar and LG are going to be similar quality.

With similar quality and warranties - the solar panel companies are all competing on price (and marketing hype) - with large quantities now available to consumers here it US at less than $1.00/watt.

Inverter quality and features do vary. You can't go wrong with SMA.  High quality (German engineering and all) - but you'll pay for it.

What IS very important for someone like yourself getting a professionally installed grid-tied system is the quality of the installation - ESPECIALLY the mounting to the roof.  Poor workmanship there will cause problems- roof leakes, damage during wind storms, etc.

Also - one factor that has been prove to have  fairly large effect on performance in warm climates is the distance off of the roof that the panels are mounted.  Temperature has large effects on panel perfomance and without adequate ventilation under the panels performance will suffer.

So when deciding between installations - I would focus on the reputation of the installers, how they physically mount to your roof and how high of standoffs they use to get the panels up to ensure adequate ventilation.

A couple of great rescources:

PV Watts2 Calculator lets you model the solar array output at your location using various parameters.

The NAWS forum is the premier forum for solar electric and other renewable energy.

Good luck.

[peterthenovice]

dave check this out

[Psi]

My opinion on the solar system is that Pluto really isn't a planet. 

Hehe

When i saw the topic title i thought... "hm.. well, i'm not against the solar system"

[Joules]

Should have hired a skip when it was built than leaving all the left over rubble and trying to give it a fancy name "Asteroid Belt" 

[EEVblog]

Bottom line is that solar panels have become a commodity product and all the large (mostly Chinese) manufacturers produce similar quality panels - despite the marketing hype.  There surely are some cut rate - poor quality panels being made somewhere but it's unlikely any professional installer is going to use them.  Trina solar and LG are going to be similar quality.

Yep, that's what I figured as well.

Inverter quality and features do vary. You can't go wrong with SMA.  High quality (German engineering and all) - but you'll pay for it.

Yep, I'm paying a lot extra for the best quality here, but I think will be worth it. Plus I like the SMA's Bluetooth interface.

So when deciding between installations - I would focus on the reputation of the installers, how they physically mount to your roof and how high of standoffs they use to get the panels up to ensure adequate ventilation.

Yeah, looking to go with this mob:
http://www.ahegroup.com.au/
Local, no negative reviews that I can find, and they are saying the right stuff I expect to hear. Some of the others weren't saying the right stuff, or any stuff.
Even have their own Whirlpool thread:
http://forums.whirlpool.net.au/forum-replies.cfm?t=1484224&p=13

[Joules]

On a more serious note...  My vote also would be for Kyocera.  It was one of the most efficient at the time we purchased and backed by a large company that should still be in business for the entire life of the warranty.  Several years trouble free service so far.

[EEVblog]

On a more serious note...  My vote also would be for Kyocera. 

None of my locals installers seem to offer those.

[ee851]

OMG, Dave, I thought you were talking about
the Sun as the provider of energy for all forms of life in this solar system.
My bad.
For photovoltaic systems, be aware the cooler the cells, the more amperes they will output.
www.homepower.com is a good resource for the nuts & bolts of making a PV system work for your home

[jnissen]

If you have any shading at all it's well worth the cost to go with micro-inverters. Enphase here in the US makes a great product and they are distributed all over. The SunnyBoy your thinking of getting is OK but one bird turd on the panel will result in the whole string suffering. Microinverters are per panel and allows you to monitor per panel production. I have an array that I installed the last couple of years and it's working great. So glad I went with the micro-inverters over the single or multiple large inverters. Dirt and leaves along with partial shading is real and will significantly impact your production.

Example of a large array: https://enlighten.enphaseenergy.com/public/systems/f9CW28621

[NiHaoMike]

The main disadvantage of such a design is that tapping into it for emergency power likely involves getting on the roof, something that is often impeded by the emergency itself. Maybe that's unlikely to be a problem in your area but if it does happen... Being able to pull just a few watts (or a few tens/hundreds of watts) can be very useful in an emergency. In theory, it's possible to make a gadget that simulates the grid and lets the inverters start,
but it would need to potentially sink the entire output of the panels, not very easy with a large system. (If you don't pull enough power, the voltage will rise and the inverters will trip on overvoltage. In general, you either have to take it all or not get any at all.)

A distributed DC MPPT design gives the same advantage without that disadvantage.

[lemmegraphdat]

Too me solar cells seem like a cool gadget but are they worth tearing into a good roof for? Could you place them on another part of the property?

[NiHaoMike]

Thermal cycling is what often causes a roof to fail, so installing solar panels or painting the roof white are actually ways to make it last longer.

[EEVblog]

Too me solar cells seem like a cool gadget but are they worth tearing into a good roof for? Could you place them on another part of the property?

Nope, not an option.
I assume they use mounting rails, so there shouldn't be too many penetrators through the roof tiles.

[EEVblog]

If you have any shading at all it's well worth the cost to go with micro-inverters. Enphase here in the US makes a great product and they are distributed all over. The SunnyBoy your thinking of getting is OK but one bird turd on the panel will result in the whole string suffering. Microinverters are per panel and allows you to monitor per panel production. I have an array that I installed the last couple of years and it's working great. So glad I went with the micro-inverters over the single or multiple large inverters. Dirt and leaves along with partial shading is real and will significantly impact your production.

I thought a shaded panel simply was bypassed with diodes and wasn't too much of a problem?

[Rerouter]

i think he might mean for parallel strings as unless they have reverse polarity blocking diodes it would pull down the voltage of the others,

[EEVblog]

i think he might mean for parallel strings as unless they have reverse polarity blocking diodes it would pull down the voltage of the others,

Yes. I'm reasonably sure my system will be series. The panels are circa 30V each, and the Sunnyboy inverter takes up to 750 input. So 12 panels can easily be done in series.

[jnissen]

There are lots of good documented comparisons of series inverters and micro-inverters. I went with micro inverters as they were clearly the most long term bang for the buck. You can do what you want to Dave but in the long run you will likely kick yourself for not doing micros. The older string inverters are cheap but like I said one bird turd and the whole series string suffers due to the bypass diode series losses.

Here is a good write up with recent comparisons.

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=9&ved=0CIABEBYwCA&url=http%3A%2F%2Flibres.uncg.edu%2Fir%2Fasu%2Ff%2FLee%2C%2520David_2011_Thesis.pdf&ei=GIGIUZn-MJLD0AGs9IHoAQ&usg=AFQjCNEpOkwga7YcKglVPZJSAOW_T7ov5w&sig2=YVq-X1elG4Oi1VprYNybdg&bvm=bv.45960087,d.dmQ

[EEVblog]

There are lots of good documented comparisons of series inverters and micro-inverters. I went with micro inverters as they were clearly the most long term bang for the buck. You can do what you want to Dave but in the long run you will likely kick yourself for not doing micros. The older string inverters are cheap but like I said one bird turd and the whole series string suffers due to the bypass diode series losses.

Can you put a real quantitative figure behind that?
I find it hard to believe (without having researched it) that one bird crap will drastically reduce the output of a large series system. If so, almost every installed system on the market would be useless.