About to take the plunge, can you double check my system

hockeyboy93551

Ok I've been reading this forum for a while now and I'm about to buy my system and just want to make sure im doing everything right. I'm looking to get a sunnyboy 11000tl inverter(about $3k) and 30 Sun 395w panels(http://sunelec.com/sun-395-watt-monocrystalline-solar-panel.html at about $7k) and some generic racking off ebay for about $1k. The inverter comes with a dc disconnect and I think im going to have to get a combiner box for about $250. Besides wiring is their anything else I'm missing? If I understand correctly with the panels im getting and the inverter im using I need to hook them up in 6 strings of 5 panels, is that correct? Any help would be appreciated. Thanks in advance!

keith

BB.

Re: About to take the plunge, can you double check my system

Welcome to the forum Keith!

Are you in the San Francisco Bay area with PG&E power?

Anyway--My first question is that solar panels that you have linked too--I do not see an UL/NRTL Listing for them.

http://sunelec.com/datasheet-library/download/SUN395.pdf

Whether or not these are good panels--Without a UL/NRTL (nationally recognized testing laboratory) label--You should not be able to get a building permit/sign-off. And without a completed building permit, PG&E will not allow you to connect to their grid, and to sign up for their Net Metering power plan.

Could it squeak through building and inspection--And get accepted by PG&E, yes, it does happen. But it is a bit of risk that nobody will catch the use of un-LISTED solar panels/components.

If you are building an off grid system (no permits, not connected to utility power for net metering)--Then the "UL" requirement may not apply.

Some other issues--I have not followed the California requirements closely--But in times past, for a system >10,000 Watts (yours is rated 11,000 watts), you may run into some more regulatory/utility requirements. Have you spoken with PG&E yet about their requirements for connecting?

Do you have a large enough AC main panel and drop from the utility to support your home (office/etc.) + GT solar requirements. There are ways to play the game, but the starting point is probably around a minimum of a 200 Amp service for you home (and could be near 300 Amp main service--depending on your loads).

And SMA has a GT Solar design tool that you should look at (if have not already):

http://www.sma-america.com/en_US/services/solar-design-tools.html

Before you open your wallet--Want to make sure all of your ducks are in a row.

Good Luck,
-Bill

Photowhit

Re: About to take the plunge, can you double check my system

I don't think you want this as a long term fixed home solar panel, It is a membrane panel with out glass. It appears to be a relabeled Sun from Suntech (Here is someone else selling it as a Suntech 395, and the original picture ad shows them selling as a Suntech); They show a photo of it in one of their mailings. Shown here;

Attachment not found.

They have remarkable price right now on Yingli which appear to be framed glass panels, also the lower VMP will mean less strigs with the Yingli panels. They say both have TUV cert. I thought California had some other rating for some credits/rebates, but I'm live in the middle so it's not my ocean...lol.

hockeyboy93551

Re: About to take the plunge, can you double check my system

Wow, how did I miss that? Thanks for the heads up. I guess I'll keep looking, I definitely need a framed panel with glass. I saw the yingli's in their ad but was unable to find them on the website, I think they might be for export only or something. Thanks for the info on the sma array sizer, it has helped a ton! Guess I'll wait till their next sale but didn't know it was harder to permit a larger system, whats the difference between 10k and 11k? I was just going for the most watts for a single inverter and price point. Do I need to downgrade to 10k or 9k to avoid the hassles? BTW I have socal Edison and not PG&E. Thanks for your help guys!

Photowhit

Re: About to take the plunge, can you double check my system

hockeyboy93551 wrote: »

I saw the yingli's in their ad but was unable to find them on the website, I think they might be for export only or something.

Click on the link at top of the main page!

hockeyboy93551 wrote: »

I was just going for the most watts for a single inverter and price point. Do I need to downgrade to 10k or 9k to avoid the hassles? BTW I have socal Edison and not PG&E.

Best place to start is to talk to the power company. Your looking at doing a long term relationship with them. They may have the info on their website.

stephendv

Re: About to take the plunge, can you double check my system

hockeyboy93551 wrote: »

I think im going to have to get a combiner box for about $250. Besides wiring is their anything else I'm missing? If I understand correctly with the panels im getting and the inverter im using I need to hook them up in 6 strings of 5 panels, is that correct?

Don't think you need an external combiner, according to the specs the 11000 accepts 6 strings on its input.

hockeyboy93551

Re: About to take the plunge, can you double check my system

What do you guys think about doing 90 of these panels? 10 strings 9, they seem to be OK and do better in high heat temps which I'm in, they cost less, but racking will be twice as expensive.

hockeyboy93551

Re: About to take the plunge, can you double check my system

http://sunelec.com/solar-panels/sharp-121w.html

Photowhit

Re: About to take the plunge, can you double check my system

I'm not a fan of thin film, These are at least framed, though I couldn't find out if they had mounting holes in the back or if they would require special mounting brackets. These have a lower Voltage than most thin film panels, as each panel is setup as 4 parrellel 'cells' which will make it easier to run fewer strings(one of the issues with thin film).

Since it would be double the amount of brackets and area, why don't you check into the Yingli panels they are selling. TUV cert and appear to be framed. I haven't called them yet, but it's a silly low price and Yingli is one of the top solar panel producer in the world. It may be that they are for sale outside of the US, but usually they state that...

BB.

Re: About to take the plunge, can you double check my system

At this point, the price of racking is about the same $$$/Watt as the solar panels themselves... If you have thin film panels that are 2x the size of crystalline solar panels--Any money you save may be eaten up in additional racking/wiring.

-Bill

hockeyboy93551

Re: About to take the plunge, can you double check my system

When you click on them it just takes you to the home page again, I called them but no one answered at either warehouse so I'm guessing they're closed.

Photowhit

Re: About to take the plunge, can you double check my system

hockeyboy93551 wrote: »

When you click on them it just takes you to the home page again, I called them but no one answered at either warehouse so I'm guessing they're closed.

after 5pm on Sunday...I'd assume they are closed. I hope to check into these Yingli panels myself. May buy a stack just as a hedge against the economy.

I've purchased from them twice and should warn you to know what your buying, ask your question NOW. don't end up with membrane panels. They are basically a wholesaler, that looks for the best deals and lowest prices. Be sure to ask if they are blemished panels, ask for the complete model number. Do your home work NOW. It isn't like purchasing from Northern Arizona Wind and Sun! Sunelec typically know what they have and are happy to sell it to you. but you must know what your looking for!

Your doing some homework now, that's good! Have you found specs for the sharp panels? The link at Sunelec is currently wrong try This Link. Thin film has some interesting characteristics, They tend to start producing 10-15% more wattage than after 6 months, The Sharps are rated for the after break in numbers. Sharp tends to be a good company, but look at the sizes, do you have enough roof space facing south to use these panels? How cool does it get where you are? can your Inverter handle the max VOC when you factor in a rise do to cold weather?

I've gotten what I've paid for and more from Sunelec. But don't expect them to baby you, The last purchase was for panels in Europe that hadn't crossed the ocean or cleared customs yet, expected delivery was 3+ month out. I didn't receive a call in that time, but they were sent and did arrive as advertised and even though I purchased FOB Miami (they arranged shipping), when one arrived cracked they replaced it at no cost to me. Hard to beat that! They were NOT responsible, since it was understood I purchased in Miami. I guess since they arranged shipping they took the hit. I would NOT expect that.

hockeyboy93551

Re: About to take the plunge, can you double check my system

I do have the PDF for the sharp panels but don't know how to calculate for the weather, it does get below freezing sometimes but not much below that, it gets as high as 110 f but that's another reason for thin films. I would like to get the yinglis but for some reason I remember them being for export only because of tariffs on Chinese panels but I could be wrong, I got a hold of someone yesterday but he said he was too busy and would have someone call me back, hasn't happened yet. I checked into so cal Edison and my max is 10kw, do you know if that goes by the inverter or the panels? I'm guessing inverter but if that's the case can't I just have 11k in panels and a 10k inverter? Most of the reading I've done said they are built to handle that because they rarely produce top wattage and there is loss anyway so it should be fine. Racking I can get for less than $10 a panel so the sharps would still be cost effective and I live on 2.5 acres so I'm OK on space just don't feel like hooking up twice as many panels for no reason. On the plus side, when my kids break one with a baseball it would only be $40 instead of over $100.

Photowhit

Re: About to take the plunge, can you double check my system

hockeyboy93551 wrote: »

I would like to get the yinglis but for some reason I remember them being for export only because of tariffs on Chinese panels but I could be wrong,

I haven't seen the yinglis in their ads until now, but that doesn't mean anything, they do a lot of business in the Caribbean.

hockeyboy93551 wrote: »

I got a hold of someone yesterday but he said he was too busy and would have someone call me back, hasn't happened yet.

Don't hold your breath, they stay very busy when they have these very cheap sales...

hockeyboy93551 wrote: »

I checked into so cal Edison and my max is 10kw, do you know if that goes by the inverter or the panels? I'm guessing inverter but if that's the case can't I just have 11k in panels and a 10k inverter?

That's my understanding, backfeeding limited to 10K

hockeyboy93551 wrote: »

Racking I can get for less than $10 a panel so the sharps would still be cost effective and I live on 2.5 acres so I'm OK on space just don't feel like hooking up twice as many panels for no reason.

If your doing grid tied, there will very likely be hoops to jump through, TALK TO YOUR POWER COMPANY!!! and not in a confrontational manner!

Requiring engineering study on the ability of the roof to support the panels is normal, If ground mounted you may be required something like this as well. NEC code requires system over 30 volts to have limited access to wiring, so that means fenced in array if ground mounted and wiring in conduit, Many more hoops are possible! Very likely need an electrician to sign off on the wiring if not wiring it them selves!

hockeyboy93551 wrote: »

On the plus side, when my kids break one with a baseball it would only be $40 instead of over $100.

Never hurts to save money! but finding more will likely be a problem, if you anticipate problems or have a 90 panel system, I would buy a few extra! It might be very hard to match up panels later incase of damage...

BB.

Re: About to take the plunge, can you double check my system

Depending on your utility and the present state rules--10kWatt and under is "residential" sized GT power systems. Between 10kW and 100 kWatt, is sort of an in-between zone where you can choose which hoops to jump through (as I recall).

Some utilities may have a limit on how much power you can backfeed without going to 3 phase (typically you can only feed 10kW "unbalanced" power into a 3 phase system). Also, for larger systems, they may have issues with how many and how large of solar power systems can back feed into their local distribution system.

All things I have picked up over the last decade--Requirements change, so the only one that can give you current information is really your utility (or local/knowledgeable solar installer--They do earn their money).

-Bill

Photowhit

Re: About to take the plunge, can you double check my system

-30(temp diff from STC 25c, I used -5c for low) x -.30(VOC temp cof)=9% (percent of increase at -5 degrees c(23 degrees farenheit).

So VOC of 60.2 x 9(panels) x 1.09 = 590.56 voc at -5c

Please note, I have never had to worry about this, I hope someone comes in and checks my work!

hockeyboy93551

Re: About to take the plunge, can you double check my system

So the yingli's are for export only and the suntechs I don't want because they are frameless and don't have glass, besides racking costs what are the disadvantages of the sharp thin films? I don't really want to rack twice as many panels but if these perform better in high heat and are half the price? Someone talk me out of them.


Keith