Sunpower 327 panels worth the cost?

[MGE]

Looking at finally installing solar on my home and was thinking about using these from Sunpower the SPR-327NE-WHT-D. I can only fit 30 panels total on the varies roof areas that are free of shadows or obstructions so I'm looking to maximize my system. System size probably about 8-9k. Anyone have any opinions on these panels, good or bad. Thanks

[bonaire]

If max power and space is a concern, sure, may be worth it to you. But also, if the system price goes up say $1/Watt after rebates and credits, will you recoup that over time? Maybe not.

If you do have any shadows and need to handle it with microinveters, Enphase will be too small for such high-efficiency modules. This would be the job for something like a PowerOne 300W microinverter or one of their dual-MPPT Aurora inverters. You say you have room for 30 shadow-free modules but could you upsize it further if you had some partial shadowing? If so, then you could use the micros.

[Naptown]

Yes they are expensive. So is a Mercedes Benz. They are the best panel on the market today. Highest efficiency, Highest power density and the 25 year bumper to bumper warranty really set them apart.

[MGE]

Thanks for the replys gents. Will do some more measuring to see if I can use more smaller size panels and live with a little bit of shading. Plan on living in this house until the end, which hopefully won't be for another 30-40 years or so. I will do more research as I'm just getting started on design and not set on anything yet. Ideally I want a 8-9k system to offset my monthly bill ( last year average monthly usage was 1347kw ). As far as inverters go string or micro which would be more advantageous I'm sure both have their advantages depending on the system design. I was told about a Solar Edge Power Optimizer is this instead of the micro or string inverters? Thanks for the great site I plan on learning a lot.

[bonaire]

The Solar Edge per-cell optimizer isn't in lieu of an inverter. It's instead of micro-inverters if you have a string inverter. http://www.solaredge.us/groups/us/po...ower-optimizer

You can use monitoring software per unit instead of looking at it from the inverter. I think it adds extra cost without offering a whole lot of payback. May as well use a good micro-inverter if you want per-module monitoring.

I look at my two Auroras every week or so and verify that the input voltage on each MPPT controller is similar. I don't have monitoring as my installer wanted to charge me an additional $1K+ to get the $320 desktop unit plus some wiring. No thanks. Drives up the cost of the system and monitoring is un-necessary to handle warranty claims. Just make sure the system is operating to spec on good sun days during peak power output. For me, I look at my 32-module array as having four inverters (two Auroras with dual-MPPT each). so, as long as they're able to show similar Voltage and Amps on each MPPT, I consider that a good cross-check to say if a string is good or has a possibility of bad panel. You can then use temperature guns or other tools to find the bad panel. I chose SolarWorld Mono 255W modules. I don't expect failures other than either: animal damage or lightning strike. Both will be very obvious.

If you have a perfect roof with no shade and no need for more than one angle of panels, a string inverter should be fine if you use modules that tend not to fail a lot. If you get Tier-4 modules that have a shorter lifespan, expect to need a way to show the output differences so you can call in warranty claims. Besides shade, that's one of the main reasons to have power optimizers or micro-inverters. But it does add additional expense over a string inverter.

[KRenn]

Thanks for the replays gents. Will do some more measuring to see if I can use more smaller size panels and live with a little bit of shading. Plan on living in this house until the end, which hopefully won't be for another 30-40 years or so. I will do more research as I'm just getting started on design and not set on anything yet. Ideally I want a 8-9k system to offset my monthly bill ( last year average monthly usage was 1347kw ). As far as inverters go string or micro which would be more advantageous I'm sure both have their advantages depending on the system design. I was told about a Solar Edge Power Optimizer is this instead of the micro or string inverters? Thanks for the great site I plan on learning a lot.

As always, my response is to compare prices and see what the variation compared to overall solar system production looks like. I love SunPower, without a doubt they are the highest quality modules on the market, but you also have to look at your eventual return and what other options may be out there. I fully recommend getting at least three quotes, and if looking at SunPower, quotes from multiple SunPower dealers as the price can vary more than you might expect.

The biggest thing is to look for high quality components from established companies, both in panel and inverter(s), look at expected production and see what the price gap looks like, as well as the likelihood of being able to get your panels serviced should you encounter any troubles down the road. If you want to have your quotes evaluated, just post the basics, system size, panel/inverter type, pricing....etc, and you'll be able to get some great responses.

If you're looking at a very tight roof space and you want to maximize the amount of power produced, then SunPower is the answer but depending on pricing, you may find it more reasonable to go with a reduced-sized system of another brand, it just all depends.

[MGE]

Thanks guys for the ideas. I think I will use another panel manufacturer based on the overall cost of the equipment I seem to have more space than I originally thought. Right now Im thinking of going with (34) SUNIVA OPT260 watt panels and using the ENPHASE M215 Microinverters which should give me about 8.8k. There is a company out here in San Diego called SCESD Advanced Solar Design Services that will do the drawings for layout, location, orientation and equipment selection to maximize the power output within the available space for about $400.00. They will walk me through the permit process, SDG&E meter change-out and all inspections with the city as far as being code compliant.
They will provide
1. (3) 11"x 17" Plan Set
2. 2D Site Layout Drawing
3. One Three Line Drawing
4. Component Specifications
5. Detailed Calcs (Amps and Volts)
6. Datasheets, Brochures and Supporting Documentation

Being an Union C-10 Electrical Contractor (soon to be retired) I should have the ability to do the install myself. Dealt with the city on permits for various jobs and even know some of the inspectors, SDG&E also being a HV Splicer having to interface with them on facility shutdowns or repairs and such.Should get the drawings from them in less than one week.
Looking forward to doing this job especially since it's at my own home.
Anyone ever hear of these guys? Seems more logical to go this way.
Thanks again

[bonaire]

Suniva is getting popular and now has US-manufacturing as well. I looked at them before going with SolarWorld 255W monos for my system. My installer talked me out of Sunivas but perhaps mainly because he wanted to include my 32-modules in with a larger order he was doing from SolarWorld. Like many installers, he sticks with what he knows rather than going for something new even if it was better. To let you know, I heard from PowerOne that they have surpassed manufacturing count goals for 2013 Q1.

Suniva also has 72-cell modules which may help you do the system with slightly less racking if you were to use these slightly larger modules. If you do use them, then consider the 300W PowerOne micro inverters. I know most systems are with 60-cell modules but I think you can gain a little cost-savings if you used less racking. That means less roof piercings and fewer stand-offs.

[MGE]

Good info. I'm still waiting for the design to come in. Will look at what they spec out and why and see if it"s workable. Will keep posting when I hear more.

[salq]

I wish I'd been looking sooner than now, I'd have offered to assist you in exchange for you assisting me with my install. I'm looking at Sunpower but no conclusions yet. The companies I've talked to so far have said there are no microinverters that work with Sunpower panel outputs (which sounds odd to me), so their only offering single inverters.

Can you share how things turned out?

Thanks.
Sal, also in San Diego

[inetdog]

The companies I've talked to so far have said there are no microinverters that work with Sunpower panel outputs (which sounds odd to me),

Not that odd:
The problem is not the voltage or the brand of the panels but rather their high power output that causes the incompatibility. Only now (since the panels are becoming more common) are microinverters capable of that total power per panel being developed and marketed.

[Naptown]

Not that odd:
The problem is not the voltage or the brand of the panels but rather their high power output that causes the incompatibility. Only now (since the panels are becoming more common) are microinverters capable of that total power per panel being developed and marketed.

Actually voltage is the problem.
Sunpower uses 5" cells that produce as much as a 6" cell
Those panels are 96 cell panels and even the power 1's can't handle it
If you need Sunpower and micro's they make AC panels in lower wattages and obviously a smaller footprint than the 327's

[salq]

Not that odd:
The problem is not the voltage or the brand of the panels but rather their high power output that causes the incompatibility. Only now (since the panels are becoming more common) are microinverters capable of that total power per panel being developed and marketed.

Yes, understood, it seemed odd to me that Sunpower would introduce a panel with a higher yield but not have all options available for inverter support. Single inverters work, and it looks like Sunpower makes a couple of them too. I'd like to know why they didn't make a microinverter. Perhaps they're just rebranding an off-the-shelf single inverter, or perhaps they haven't gotten around to it yet. Some indication of how long I'd need to wait would be nice, which is a good question to ask them right now...

[Naptown]

All Sunpower inverters are rebranded
SMA, Fronius or power one
Not sure who makes their micros

[salq]

For what it's worth...

Chat Transcript
Welcome! A Solar Advisor will be with you shortly.
You have been connected to Chris .
Chris : Hi Sal, thank you for your interest in SunPower, my name is Chris and I am your Solar Advisor for today.
Chris : Thank you Sal. I've read your query. Give me 2-3 minutes while I consult our Technical Support Team about it.
SalQ: thanks
Chris : I appreciate your patience in waiting for a response Sal. Currently, our ACPV are for 72-cells modules only (SPR-225, SPR-240). Gen 2 ACPV will be for SPR-245 modules. We don't have ACPV with 96-cells modules as of now.
SalQ: ACPV? I'm just getting started, with only the perspective that there are single inverters and microinverters, and the 327V output of the Suntech panels have no microinverters today that work with them. Are you saying that the solution today is to get a smaller Sunpower panel?
SalQ: (if I want microinverters)
SalQ: still there?
Chris : Yes Sal. I'm waiting for the team's response. One moment please.
Chris : Thank you for waiting. We have not known any microinverter that will work with our SPR-327 modules. Few manufacturers might claim that they have a model that can work, however, we have not tested any microinverter with our SPR-327 so we cannot guarantee that it will work.
SalQ: Sunpower makes a single inverter, right? Or is it re-branding someone else's inverter...
Chris : Sal, SunPower only manufacture Solar modules. All inverters that we are selling are from other manufacturer that we re-brand.
SalQ: ok. So no ETA on microinverters then, no active work being done?
SalQ: with a potential partner?
SalQ: Sunpower warranties their panels for 25 years, so for all I know Sunpower has decided that it can't endorse microinverters because the lifespans are unacceptable. I'm trying to find the answers to "why" to help my purchase decision.
Chris : We have partnered with Solar Bridge that manufactures microinverters. We are not selling microinverters though as a stand alone product. We are selling microinverters bundled with our modules that we call ACPV. With our ACPV the micorinverters are installed in our factory.
SalQ: Is that available for residential installs? For some reason, 3 San Diego Sunpower dealers are pushing only the SPR-327.
Chris : Our ACPV are for residential application only. We do not recommend ACPV for commercial installations. We are not endorsing other microinverters with our modules for the reason that we have not tested them with our panels.
SalQ: Sorry, this entire conversation is about residential. So to be clear, ACPV includes micro inverters and are therefore endorsed for residential, correct?
Chris : Yes Sal.
SalQ: Ok, so now that we're in sync, do you have any idea why the local dealers aren't mentioning ACPV at all, particularly when I bring up micro inverters?
Chris : No, we have no idea Sal.
SalQ: That's fair.
SalQ: All 3 show up on the list of local qualified Elite SunPower dealers. Is there any way to identify the dealer that knows SunPower options fully? Obviously your competition is pushing microinverters as the disadvantage of using SunPower, but I do like the 25 year warranty.
Chris : All of our Dealers must complete our certified training program, but they also must continue to earn high marks from our customers. On the other hand, they have their own market strategies. By the way, just to add, our Dealers are aware that we do not sell microinverters. Their concept of microinverters might have been installing individual inverters to our panels, unlike our ACPV that our panels came with the microinverters. Our Dealers might also thought that ACPV is not the best option for system, specially if you have a large unshaded roof.
SalQ: They knew I was an engineer and gave me the URL to their website, so though they may have thought that ACPV was not the best option, it seems odd that me bringing up micro inverters doesn't tell them to explain it. They did bring up non-shaded roof, but there are at least a couple of white papers online about the efficiency of energy capture for single inverters and micro inverters, including non-shaded areas, showing micro inverters as more efficient (and if SunPower had a similar white paper explaining that that's not the case, that would be great, but I can't find one on the site so far). As far as not being aware of ACPV, that seems to be against "certified training program". So it sounds like you can't refer me to a vendor who knows the SunPower options available, since you can't know whether dealers understand the options available (no attitude to that statement, I just want to make sure I'm understanding correctly).
Chris : My apologies but we provided our Dealers equal standard trainings. We're unable to gauge their complete knowledge but we're making sure to have every information about our products on the tools we provide them. So it'll be unfair if I'll recommend you to one Dealer and compare one from another.
SalQ: It sounds like I need to read that as "not certified", otherwise you would have a guage.
SalQ: gauge
SalQ: But I believe I understand now. No timeframe on micro inverters being supported on the 327s, no timeframe on an ACPV equivalent using 327s, and no study on why single is as good as or better than micro inverters under certain conditions. Correct?
Chris : Yes Sal, your correct with no time frame on microinverter supporting SPR-327 and ACPV equivalent to SPR-327.
Chris : In terms of study which is better between string inverters and microinverters, we believe there is.
SalQ: Yes, I've found them, micro is listed as 20+% better.
Chris : Alright.
Chris : In addition, this analysis takes place in the design phase that you will need to consider economics and performance of your system.
SalQ: That makes sense. I just need to find someone who knows all the options to do a full analysis.
SalQ: Thanks for your time. If there's anything else you think I should know that might help based on our conversation, I'd be happy to hear it. I'll be posting this on SolarPanelTalk for additional feedback online.
Chris : Okay then. Is there anything else I can assist you with aside from your initial inquiry?
SalQ: I guess not, but thanks for letting me know about ACPV.
Chris : Thank you for chatting with me. Feel free to contact us again through chat or call us at 1-800-SUNPOWER (1-800-786-7693). I'm glad to have served you. Have a great day Sal!
SalQ: you too
Your session has ended. You may now close this window.

One particularly interesting takeaway, on their ACPV panel / micro inverter combos, everything gets the 25 year guarantee.