San Marcos San Diego new System Quick

[katass1031]

You'll get about the same annual output from 1kW of LG 315's or SP 327's. I did a cost/benefit analysis for S.P. vs. a more standard panel like an LG 300. Short answer: A Sunpower paneled system is worth roughly about a 5% or so premium over 12 years with what I believe are reasonable but still variable assumptions, starting with neither system will have a failure. 8% is obviously outside that premium margin, but other non financial factors may come into play to tip the balance.

If I went further w/ the S.P. quote, I'd make sure of the details on that S.P. price and make sure they're not used, sloppy seconds, or counterfeit. $3.72 is lower than usual for S.P. by a lot. I'd love to see it, but I'd sure trust but verify. If a deal seems too good to be true, it probably is.

They are a SunPower Premier dealer, so I can only assume he is telling the truth. According to his output analysis, 20 LG310s provide 10250 kWh/yr and 19 SP 327s provide 10330 kWh/yr, which is almost negligible.

Looking at the 25 year warranty of the SPs sure looks nice to go with the 25 year warranty of the rest of the system (once I pay to upgrade the inverter).

[katass1031]

Is there a advantage or disadvantage to having the inverter in the garage or outside? I see of a lot of installs on the outside and don't really like it.

[thejq]

Is there a advantage or disadvantage to having the inverter in the garage or outside? I see of a lot of installs on the outside and don't really like it.

If you have room inside and it's well ventilated, it's better to keep it inside and away from the elements and possible vandalism. Your latest quote sounds a lot more reasonable. At 8.1% premium, you might want to seriously consider S.P. FYI, unlike others, their warranty actually covers replacement labor.

[katass1031]

Say I go with Sunpower and in 30 years the panels are no longer good, what happens then? Where do the old panels go? Say panels are the same size as they are today, could I go with LG and would they fit on the same mounts?

[thejq]

Say I go with Sunpower and in 30 years the panels are no longer good, what happens then? Where do the old panels go? Say panels are the same size as they are today, could I go with LG and would they fit on the same mounts?

No one can predict what will happen that far out. Your roof probably won't last that long. You make the decision based on what you know today and hope for the best. With SolarEdge optimizer, you can replace a broken panel with any panel as long as it fits the space. If you also need to swap out an optimizer, SolarEdge also needs to be around to provide the parts.

[sensij]

He told me that these X20-327s are the same panels as the X21-345 that do not meet the criteria for the 345s and are calssified as a step below because they do not produce enough watts. Basicall the 345s need to create greater than 346W, if not, then they are classified as the 327s.

Is it worth the $1500 premium for the SunPowers?

I'm pretty sure this guy is lying to you. Look at the data sheets on those panels... the 327 uses Gen II cells, the 345 uses Gen III. They are definitely not the same thing.

[katass1031]

I'm pretty sure this guy is lying to you. Look at the data sheets on those panels... the 327 uses Gen II cells, the 345 uses Gen III. They are definitely http://us.sunpower.com/sites/sunpower/files/media-library/white-papers/wp-ieee-3rd-generation-solar-cell-high-efficiency-lower-cost-technology-transition-full-scale.pdf"]not the same thing[/URL].

Maybe you are referring to the e327. The x20-327 and the x21-345 look like they are both gen 3 according to this.

http://us.sunpower.com/sites/sunpower/files/media-library/spec-sheets/sp-x-series-residential-solar-panels-supplementary-technical-spec.pdf

[J.P.M.]

Maybe you are referring to the e327. The x20-327 and the x21-345 look like they are both gen 3 according to this.

http://us.sunpower.com/sites/sunpowe...nical-spec.pdf

While there were probably some evolutionary tweaking, I kind of suspect some of the Gen II /Gen III STC output difference was/is a marketing toll. That is, the 327's may well have always overproduced (conservatively rated), Maybe like 335 W or somewhere between 327 and 335 W ? Maybe/probably the 345's are an evolutionary treak of what were 327's, with the subsequent production runs all the same, with those flashing at 345 Watts or more labeled as such and those flashing lower labeled and sold as such.

Such a scheme seems easier to me than 3 separate production lines (327's, 335's and 345's) and mfg. processes for panels only 10 or so Watts apart in STC rating.

FWIW, I'm pretty sure - educated SWAG - my 327's would flash at ~ 330-335 W or so on a test when they were new.

[J.P.M.]

Say I go with Sunpower and in 30 years the panels are no longer good, what happens then? Where do the old panels go? Say panels are the same size as they are today, could I go with LG and would they fit on the same mounts?

Do as you wish, but 30 years from now is a long time to worry. Things may well not even use solar power by then.

[sensij]

Maybe you are referring to the e327. The x20-327 and the x21-345 look like they are both gen 3 according to this.

http://us.sunpower.com/sites/sunpowe...nical-spec.pdf

That reference is only looking at the frame. I am talking about the "Maxeon" cells. The reference I cited is very clear that different production lines produce different generations of cells.

Looking more closely, it seems there are two versions of the 327's... The E-series and the X-series. The E series used gen 2 cells, while the X uses gen 3.

You might want to get your dealer to confirm which specific 327 panel is being quoted.

http://www.pv-tech.org/news/sunpower_lifts_lid_on_new_record_21.5_efficient_x_series_solar_modules

[J.P.M.]

Is there a advantage or disadvantage to having the inverter in the garage or outside? I see of a lot of installs on the outside and don't really like it.

Goods/not so goods. The air and interior surfaces of an insulated garage will get warmer by the 3-4 % inverter inefficiency that shows up as a heat source in the garage. A standard leaky/uninsulated garage will heat up less, but some. That increased temp., whether a lot or a little will impact the inverter temp. some, and perhaps be of a concern in warm and sunny weather. OTOH, the inverter will be out of the elements and less subject to vandalism which may/may not be a concern. If located outside, most inverter mfg's suggest avoiding locations in direct sun or exposure to a lot of moisture or very cold temps. Outside breezes can help the unit run cooler but are variable and unpredictable.


FWIW, mine's in the garage w/ a high tech window fan blowing on it in warm/hot weather. Most of this business is not rocket science.

[katass1031]

Goods/not so goods. The air and interior surfaces of an insulated garage will get warmer by the 3-4 % inverter inefficiency that shows up as a heat source in the garage. A standard leaky/uninsulated garage will heat up less, but some. That increased temp., whether a lot or a little will impact the inverter temp. some, and perhaps be of a concern in warm and sunny weather. OTOH, the inverter will be out of the elements and less subject to vandalism which may/may not be a concern. If located outside, most inverter mfg's suggest avoiding locations in direct sun or exposure to a lot of moisture or very cold temps. Outside breezes can help the unit run cooler but are variable and unpredictable.


FWIW, mine's in the garage w/ a high tech window fan blowing on it in warm/hot weather. Most of this business is not rocket science.

Can you post a picture of what that fan looks like?

[katass1031]

That reference is only looking at the frame. I am talking about the "Maxeon" cells. The reference I cited is very clear that different production lines produce different generations of cells.

Looking more closely, it seems there are two versions of the 327's... The E-series and the X-series. The E series used gen 2 cells, while the X uses gen 3.

You might want to get your dealer to confirm which specific 327 panel is being quoted.

http://www.pv-tech.org/news/sunpower_lifts_lid_on_new_record_21.5_efficient_x_series_solar_modules

He most certainly said X series.

[Willaby]

Is there a advantage or disadvantage to having the inverter in the garage or outside? I see of a lot of installs on the outside and don't really like it.

I'm with you: Inside the garage was in my contract and NO conduit on the outside stucco. I did the conduit myself though, upper attic, through the interior walls, then into the garage. The only thing on my exterior is the red placard.

Regarding the temperature, my garage is insulated, but still can get to +90 degrees. The SE5000 inverter shows temp, so you can monitor and see if you might want to add a fan (as JPM has done). I was going to add a computer fan powered by a small 5w panel, but temps have never gotten greater than warm to touch, so I've put this off. Maybe in summer. I don't think I've seen the temp read more than 120 although the heat sink has shown ~130 on the hottest summer day. I doubt the ~200w of inverter inefficiency will do much to heat a garage space more than a degree or two.

[Willaby]

No one can predict what will happen that far out. Your roof probably won't last that long. You make the decision based on what you know today and hope for the best. With SolarEdge optimizer, you can replace a broken panel with any panel as long as it fits the space. If you also need to swap out an optimizer, SolarEdge also needs to be around to provide the parts.

I'd be more concerned with Enphase not being around awhile since they are now effectively a penny stock, but SolarEdge could be close behind and with 30 years to go who knows? I wouldn't be too concerned with getting replacements or parts, etc. There is enough out there and someone somewhere will repair them or hold new old stock of them. They'd likely be a bit more expensive, but attainable. More likely, the companies will get acquired and/or compatibles will be available, from LG, for example. You can still get tubes for radios and tv's that haven't been made since the 50's-70's. Many are still made.