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  • Yaryman
    Banned
    • Aug 2015
    • 245

    #76
    This is an ad from the company that makes the best panel and has an amazing "misleading" ad.

    They compare a 345 watt panel with a 250 watt panel, put that information in the fine print, and then claim 70% better production.

    Really??




    sunpower.jpg

    Comment

    • inetdog
      Super Moderator
      • May 2012
      • 9909

      #77
      It is completely honest, in that the higher output SP panel fits in the same space on the roof as the lower power panel.
      You just have to recognize that is what they are sayin.
      But for most people price per watt is more important.
      SunnyBoy 3000 US, 18 BP Solar 175B panels.

      Comment

      • Yaryman
        Banned
        • Aug 2015
        • 245

        #78
        inetdog,

        Really, you are telling me they are not trying to be deceptive.

        70% more energy in the same space.

        When the truth would be more like this.

        70% more energy when compared to a smaller sized panel of a lesser quality and cost in the same space.

        When somebody has to bullsh*t you to prove their product is worth the extra money, most likely it's not.

        Comment

        • inetdog
          Super Moderator
          • May 2012
          • 9909

          #79
          How much smaller is the comparison panel?
          SunnyBoy 3000 US, 18 BP Solar 175B panels.

          Comment

          • Yaryman
            Banned
            • Aug 2015
            • 245

            #80
            It's right there in the bottom of the photo I posted.

            Sunpower 345W compared to Conventional 250W panel. It mentions 9% more energy per watt. That's OK.

            But the problem is, SunPower is CHARGING way MORE than 9% per watt for their panels.

            Comment

            • inetdog
              Super Moderator
              • May 2012
              • 9909

              #81
              Originally posted by Yaryman
              It mentions 9% more energy per watt.
              You mean 9% more energy per nameplate watt per year?
              Energy per watt is a somewhat strange description.

              SunnyBoy 3000 US, 18 BP Solar 175B panels.

              Comment

              • sunnyguy
                Member
                • Apr 2015
                • 248

                #82
                This is what they are really claiming, best case against a crappy 15% panel:
                SunPower X-Series solar panels produce 21% more energy per rated watt over the first 25 years


                It will not be that good compared to something like LG neon.

                Comment

                • cebury
                  Solar Fanatic
                  • Sep 2011
                  • 646

                  #83
                  Originally posted by Guest
                  LOL

                  Really 75% is conservative.

                  Guaranteed degradation for a Lease is .25% LG average degredation (http://www.lg.com/us/commercial/sola...lg-LG360N2W-B3) is .6%= .35% difference
                  8% more energy per rated watt (SP rates their panels at 8% less than their actual production)
                  No light induced degredation = 2% more from day one

                  All added up: .35%+2%+8%=10.35%

                  10.35% * 20 years for the typical SunPower Lease= 207% more for the same size system if you really want to get serious about it.

                  Wow math really wasn't in his toolbox, ha. His employer should give him a 1% raise this year, because it's really a 20% raise if he stays long enough.

                  Kicked account in a short few hours, that was fast.

                  Comment

                  • Yaryman
                    Banned
                    • Aug 2015
                    • 245

                    #84
                    Originally posted by inetdog
                    You mean 9% more energy per nameplate watt per year?
                    Energy per watt is a somewhat strange description.
                    Straight from the ad.

                    "70% more energy in the same space over 25 years1"

                    "
                    1. SunPower 345W compared to a Conventional Panel (250W, 15.3% efficient, approx. 1.6 m2), 9% more energy per watt, 0.75%/yr slower degradation. BEW/DNV Engineering "SunPower Yield Report," Jan 2013, with CFV Solar Test Lab Report #12063, Jan 2013 temp. coef. calculation. Campeau, Z. et al. "SunPower Module Degradation Rate," SunPower white paper, Feb 2013. Seewww.sunpowercorp.com/facts for details."

                    If you saw a Ferrari ad that claimed -


                    "70% more speed on the same road1"
                    1. Ferrari produces 70% more speed on the same road when compared to an economy priced Kia.

                    You would know it was bullsh*t.

                    Why isn't is BS when Sunpower does it?



                    Comment

                    • rhedayi
                      Member
                      • Apr 2015
                      • 83

                      #85
                      Wait.....70% more energy in same space means...if you have a roof that holds 10 panels (actual space), you can place 10x345 vs 10x250. So that alone is a difference of 38% more power in the same space. Add degradation over time, it may add up to 70%. RIght from the start you get 38% more power in the same space, sure you pay for a 3.45kw sunpower system verseu for chinese 2.5kw system. But space is space.

                      Comment

                      • DanS26
                        Solar Fanatic
                        • Dec 2011
                        • 987

                        #86
                        You guys need an accountant to figure this out.....a 345 watt Sunpower panel (with a 9% greater efficiency factor) vs a 250 watt Chinese (with a .75% greater degradation factor) will out produce the Chinese by 65.3% over a 25 year life in the same space and assuming both panels receive an average 7 sun hours a day.

                        But a 345 watt Sunpower will cost ~$2.50/watt or $862.50 for the panel. The 250 watt Chinese will cost ~$1.00/watt or $250.00 for the panel. Dividing the panel cost by lifetime production results in the Sunpower panel costing $.03591 per watt of production vs the Chinese at $.01720 per watt of production.....a significant cost difference. The only reason you would install a Sunpower is if you are space constrained. Cost wise it is a poor economic decision.
                        Last edited by DanS26; 03-05-2016, 06:18 PM.

                        Comment

                        • sunnyguy
                          Member
                          • Apr 2015
                          • 248

                          #87
                          If you take the 1.21 energy/w and the 1.38w/area you get 67% but if you are space constrained you should look at lg and solar world.

                          For lg 315 it drops to 1.095w/area and probably 1.1 energy/w so now you're down to 20% and if lg is $1.15/w then sunpower should be $1.38/w.

                          FWIW, someone had mentioned they were getting insider pricing on sunpower panels at $1.04/w.
                          Last edited by sunnyguy; 03-07-2016, 12:24 AM.

                          Comment

                          • LLB
                            Junior Member
                            • Aug 2015
                            • 36

                            #88
                            Originally posted by DanS26
                            You guys need an accountant to figure this out.....a 345 watt Sunpower panel (with a 9% greater efficiency factor) vs a 250 watt Chinese (with a .75% greater degradation factor) will out produce the Chinese by 65.3% over a 25 year life in the same space and assuming both panels receive an average 7 sun hours a day.

                            But a 345 watt Sunpower will cost ~$2.50/watt or $862.50 for the panel. The 250 watt Chinese will cost ~$1.00/watt or $250.00 for the panel. Dividing the panel cost by lifetime production results in the Sunpower panel costing $.03591 per watt of production vs the Chinese at $.01720 per watt of production.....a significant cost difference. The only reason you would install a Sunpower is if you are space constrained. Cost wise it is a poor economic decision.
                            This seemd like a good thread to revive instead on starting a new one.

                            If you are in the city you are "almost" always space constrained. What I mean by that is, you may have 2500sqft of roof that can hold 50 panels and you only need ~20. But you only have limited sqft of south roof.
                            So I think an interesting thought experiment would be at what point does the space constrained argument even lose once you have to go to the W or E roof?
                            If you need 16 SP panels and only 12-13 fit on your S roof and you have to put the rest W or E and W or E has plenty room. Is it then better to go with say 20 LG panels even though only half face S and the rest W or E? Unfortunately it is beyond my math abilities.

                            second point
                            Are we saying that there are no SP farms. All commercial customers bean-counting accounting depts always steered away from SP? Oh wait, they did it at cost or a loss for the marketing "Brand recoginition". Maybe they just like living in the high-markup residential arena.

                            last point
                            I have only come across 2 times someone mentioning the actual patented construction. Once it was brought up as a copper heat-sink which I think was an injustice.
                            Then the strawman arguments stared flying.
                            I do not care for SP jumping-the-shark marketing either, but marketing is marketing and that's their job, to stand out and set themselves apart.
                            So maybe getting a patent is just another market maneuver, but it does come across to me as a more solidly built cell that will "last longer" while giving higher output because of the better degradation numbers. Only time will tell as no one has reported their readings from their 35yr. old SP panels with the copper backing, accelerated aging tests be damned.

                            So if you don't plan on adding to your system or moving and only want to buy once then SP I think is worth it. (If you didn't pay a 20% premium which I keep hearing about). Hopefully if more and more people report their numbers it will bring SP more in line and keep them from trying for the 20% which could get them cut from the bidding process.
                            19 SPR X21 345 / SMA 6000TL-US22

                            Comment

                            • ButchDeal
                              Solar Fanatic
                              • Apr 2014
                              • 3802

                              #89
                              Originally posted by LLB

                              This seemd like a good thread to revive instead on starting a new one.

                              If you are in the city you are "almost" always space constrained. What I mean by that is, you may have 2500sqft of roof that can hold 50 panels and you only need ~20. But you only have limited sqft of south roof.
                              So I think an interesting thought experiment would be at what point does the space constrained argument even lose once you have to go to the W or E roof?
                              If you need 16 SP panels and only 12-13 fit on your S roof and you have to put the rest W or E and W or E has plenty room. Is it then better to go with say 20 LG panels even though only half face S and the rest W or E? Unfortunately it is beyond my math abilities.
                              this is an old thread. Other brands have very similar efficiency now taking away the little sunpower advantage.

                              As for the longevity, well warranties are only as good as the company backing them.

                              E and W are at worst 20% less production than S and often closer to 15% or even 10%
                              W in some locations is actually financially better than south due to TOU billing changes.

                              OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNH

                              Comment

                              • J.P.M.
                                Solar Fanatic
                                • Aug 2013
                                • 15015

                                #90
                                Originally posted by LLB

                                This seemd like a good thread to revive instead on starting a new one.

                                If you are in the city you are "almost" always space constrained. What I mean by that is, you may have 2500sqft of roof that can hold 50 panels and you only need ~20. But you only have limited sqft of south roof.
                                So I think an interesting thought experiment would be at what point does the space constrained argument even lose once you have to go to the W or E roof?
                                If you need 16 SP panels and only 12-13 fit on your S roof and you have to put the rest W or E and W or E has plenty room. Is it then better to go with say 20 LG panels even though only half face S and the rest W or E? Unfortunately it is beyond my math abilities.

                                second point
                                Are we saying that there are no SP farms. All commercial customers bean-counting accounting depts always steered away from SP? Oh wait, they did it at cost or a loss for the marketing "Brand recoginition". Maybe they just like living in the high-markup residential arena.

                                last point
                                I have only come across 2 times someone mentioning the actual patented construction. Once it was brought up as a copper heat-sink which I think was an injustice.
                                Then the strawman arguments stared flying.
                                I do not care for SP jumping-the-shark marketing either, but marketing is marketing and that's their job, to stand out and set themselves apart.
                                So maybe getting a patent is just another market maneuver, but it does come across to me as a more solidly built cell that will "last longer" while giving higher output because of the better degradation numbers. Only time will tell as no one has reported their readings from their 35yr. old SP panels with the copper backing, accelerated aging tests be damned.

                                So if you don't plan on adding to your system or moving and only want to buy once then SP I think is worth it. (If you didn't pay a 20% premium which I keep hearing about). Hopefully if more and more people report their numbers it will bring SP more in line and keep them from trying for the 20% which could get them cut from the bidding process.
                                I question the usefulness of dredging up old threads. This one seemed to have fried the S.P. marketing B.S and stuck a fork in it, but the S.P. B.S. persists even if the S.P. price premium may have dropped a bit. More proof that there's a sucker born every minute. They're probably headed for two price/quality system now that they've bought SolarWorld.

                                You don't need a thought experiment, just a little knowledge of the time value of money and a spreadsheet, and maybe a little bit of knowledge about process economics/time value of money stuff, but arithmetic, a spreadsheet and a brain will do quite nicely.

                                These days, what was a drudge 30 - 40 years ago (believe me - did it lots by hand and paper spreadsheets - well, with a calculator too) is now a cake walk.

                                Synopsis:
                                - Find the LCOE of PV production for various orientations of 1 STC kW PV at various orientations using assumptions that fit your situation and your lifestyle for the length of time you deem appropriate.
                                - Then, compare those LCOE's to the LCOE of any alternate (like grid supplied) sources of power. If alternate (like grid power ) LCOE's are less, and cost effectiveness is the criteria, PV is not an option
                                - Also compare any PV LCOE to the levelized costs of any savings from conservation measures done before PV as most common conservation measures will almost always be more cost effective.
                                - Run different sizes of array to get the best (least LCOE combination) mix of PV and conventional method of meeting the load.
                                - Iterate by varying array sizes and orientations for different equipment mfgs. Choose the mix of conservation, PV (electrical) size and equipment mfg. that produces the lowest overall LCOE that fits your lifestyle and PITA tolerance level.

                                With LCOE type analysis (a form of lifecycle cost analysis for estimating the long term cost of producing (or buying) energy), if you use realistic (whatever that means when talking about the future) assumptions, and are honest with yourself about it by taking the time and making an effort to understand the basics, you will likely find that after reasonable conservation measures and a few possible lifestyle adjustments, PV from S.P. will have a very hard time competing with most any other quality manufacturers' equipment in terms of cost effectiveness. You may also quite likely find that offsetting 100% of a conservation reduced electrical load has a higher LCOE than simply living without PV, at least until PV prices change more than the estimates your LCOE analysis uses, or POCO prices rise more than your LCOE analysis uses.

                                Overall and in spite of what those with skin in the game and all their advert. hype, innuendo, half truth, twisted logic and just plain B.S. would have you believe, residential PV may not be cost effective for many, even most residential consumers, particularly those who are ill informed about its possibilities and more importantly, its limitations.

                                Everyone who tells you what you think sounds nice is necessarily your friend or teeing you the truth.

                                Take what you want of the above. Scrap the rest.

                                Comment

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