Suntech 280 watt panels and design ideas

[gtojohn]

He folks I've been mulling over the details to get so called free power from the sun. My utility has a great rebate of $2.50 per watt, plus the 30% federal incentive makes things affordable. The caveat is the utility will only rebate panels that get 5hrs of sun or more year round. What they've approved for me is space that will fit about 12 panels.
Every solar contractor I've had out is pushing 185 watt panels. I know this is because this is the best price. What I keep telling each one is the total output is more important. I was looking at 230-240watt panels and last night I found the 280watt Suntech modules!!
My needs are closer to 6kw and I feel 185w modules yielding 2220w won't be worth it, but 280w modules yielding 3360w would justify the cost. I was hoping to use enphase micro inverters but would go full size inverter to capture more power. I bet in 6 months there will be higher capacity micros available.

Does anyone have experience with the Suntech 280 watt panels? I found them for $613 for non dealer pricing. Is Anywhere cheaper? Are there more powerful pvs out there?

[Mike90250]

The caveat is the utility will only rebate panels that get 5hrs of sun or more year round. What they've approved for me is space that will fit about 12 panels.

So, do the 280W panels fit in that space, or are they larger ?

What is the workmanship, and power warrantys on the panels, do they loose 20% in the first 2 years ? What if they develop an internal flaw, what's the replacement on that ?

micro inverters vs wall mount - if the panels are all in sun, all the time, you don't need the microinverters, which are a solution to partially shaded roof's

[russ]

A great tool for comparing panels is http://www.solardesigntool.com/compa...s-modules.html

Select the panels you are interested in and see the specs side by side.

Generally the higher wattage panels simply mean larger physical size.

Russ

[greg kindy leed ap]

Isn't 185W for a module a bit dated? Seems like it pencils out fine to go with a 200W. Just be careful about power tolerance.

Read the spec sheet. Look for +/- 5%. Consider "positive-only" power tolerance as well. A 200W with a +10/-0 will according
to some manufacturers produce between 200 - 220W.

[russ]

+ or - tolerance is no problem - you just have to subtract the minus from the published rating and ignore the positive. You know you get that much and anything extra is a bonus.

TCoP is also important - this panel has something like 0.47% capacity loss per degree C over 25

[greg kindy leed ap]

Interesting you mention that. Is there a chart somewhere regarding capacity loss per degree - when rooftop temps get to 100 degrees Fahrenheit up to the mentioned 120 degrees Fahrenheit? With specific data about those losses within the temperature range?

I'm thinking a chart would be helpful, comparing crystalline module manufacturers like Schott, Kyocera, Sharp, SolarWorld, and SunPower. A few of the top thin film companies too.

[Sunking]

Interesting you mention that. Is there a chart somewhere regarding capacity loss per degree - when rooftop temps get to 100 degrees Fahrenheit up to the mentioned 120 degrees Fahrenheit? With specific data about those losses within the temperature range?

I'm thinking a chart would be helpful, comparing crystalline module manufacturers like Schott, Kyocera, Sharp, SolarWorld, and SunPower. A few of the top thin film companies too.

Each panel has it's own TCop You will have to make a chart fo reach one you are interested in.

[greg kindy leed ap]

Oh I see, Sunking. Well anyway... that's what I'm doing.

[So solar]

The 280 watts will be larger and may not. Fit into the space. Plus, I think the suntech 175-185 recently started to be sold to installers at good price/watt. Maybe making room for larger watt modules.

[gtojohn]

suntech

quality and workmanship? I don't know, that's why I'm asking here. According to the specs on the link everything seems pretty typical. 25 year warranty. There isn't a lot of info on these, makes me a little skeptical. One site says they have a factory in Goodyear AZ. Panels are 77x39, just a little bigger than a typical 230w panel. I do have some shading, enphase would be nice. However the bigger company, who do the most installations in our city, just recommended a sunnyboy. Again I think he was giving me the lowest price, which isn't what I'm asking for, highest output is what I want. The contractor I like has less "sales" experience and more installation experience, and is more flexible on design and my role. House is in Austin TX, over 60 days in a row of 100 degree days was the record last year. I've measured roof and other materials in the direct sun between 130-150F, I do understand this degrades performance.

[russ]

As I mentioned above - the panel spec for TCoP calls for 0.47% per

[So solar]

Heat creates resistance. Therefore lower voltage, less wattage. I think SMA Sunny Boy makes a descent inverter. Although I've seen them fail after 6 years. One year after warranty. But that's far and few. Inverter location can effect longevity. The efficiency rating is high and is suitable for the input voltage required for the modules. Xantrax had a huge recall on inverters and Fronius is not a good product. There are definitely better modules out there. You can tell your contractor what you want. But you may have to wait longer for the product. My guess is he bought the suntech about a 1.75/ watt. Yinglii solar makes good modules. But there's a wait for product.

[Mike90250]

.......Xantrax had a huge recall on inverters ......

recall is only about a input filter board on their "GT" series ony, they can/will ship the owner a replacement and a check for labor.

Everybody is getting burned, or will be burned, by counterfeit parts, and the 3 caps on the filter board, were not designed to fail. There was a huge mess with computer motherboards a few years ago, and nearly every major electronics mfg has been burned by counterfeit caps.

[So solar]

25000 inverters over a 5 year period. Its kinda large. And alot of people will get burned. Hopefully not by the covers exploding off the inverter. Do you happen to know what gas was being produced to cause this?

[Mike90250]

I think there have only been 5 verified incidents of this. (as of last week when I read about it) There are 3 large caps on a user accessible board, that is simple to replace. I think they extended the recall to the entire GT line, because the replacement is simple,and the bogus parts so prevalent.. I bet they have a very stern talk with their suppliers.