Announcement

Collapse
No announcement yet.

Sun Power Vs Solar World

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Sun Power Vs Solar World

    I have been quoted by the same company for 2 different systems and I need some help deciding what to go with.

    9.1 Kw Sun Power system for 38k - Panels have 25 year warranty

    9.5 Kw Solar World system for 30k - Panels have 10 year warranty

    Is it worth the extra money to get the Sun Power system?

    Thanks for the input

  • #2
    More information about system prices, your annual energy consumption, your electricity price, and your solar exposure (orientation, shade, etc) is needed to offer a thought out response. So, instead, I'll play the odds and say that no, buying the Sunpower system is not worth the extra money.
    CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

    Comment


    • #3
      Originally posted by sensij View Post
      More information about system prices, your annual energy consumption, your electricity price, and your solar exposure (orientation, shade, etc) is needed to offer a thought out response. So, instead, I'll play the odds and say that no, buying the Sunpower system is not worth the extra money.

      Thanks for your response.

      Just purchased the house last year. 3100 sq and I used just under 13000kWh last year, but We are very conservative with our AC in the summer and would like to keep our house cooler then we did last year. We are also talking about installing a pool in the next 5 years.
      Both of these prices are for ground mounts with no shade issues. And facing south. We are in the Central Valley in ca where summers can stay between 100-108 for days on end.
      There wil be 28 sunpower panels or 38 solar world panels. I have read good reviews on both panels and I know the sunpower has a better warranty but I'm not sure if it's worth 8k extra to get them.

      Comment


      • #4
        1.) Are those prices before or after tax credit ? Seems low for a ground mount.

        2.) Either panel will produce about the same amount of electricity over a year per installed kW. In the opinion of many, Sunpower has no meaningful advantage by any realistic, useful economic measure for the price paid.

        3.) Either system will produce something like 1,600 or so kWh/yr per installed kW. So, to offset 13,000 kWh/yr (And offsetting all of it may not be the most cost effective choice BTW), a back of envelope size might be: 13,000/1,600 = ~ 8.12 kW. Size for your realistic projections, not your dreams and don't oversize.

        4.) Run PVWatts for both panels and use the premium choice for the Sunpower panels, standard choice for the Solarworld.

        5.) Either panel will probably give good service for as long as most folks will own them. The S.P. warranty is overkill and oversold. The S.P. lower annual degradation is difficult if not impossible to verify for a warranty claim and in any case ins't worth - in your case - a 30+ % premium.

        6.) Sunpower's vaunted and touted "highest efficiency" claim is based on [U]area[/U] efficiency - Output/m^2. In terms of what most people care about = $$ paid for the system vs. $$ saved on an electric bill, Sunpower is usually and most often the "lowest efficiency".

        7.) I'd get a few more quotes.

        8.) Choose your vendor with at least as much care as the equipment, or more.

        Comment


        • #5
          Originally posted by J.P.M. View Post
          1.) Are those prices before or after tax credit ? Seems low for a ground mount.

          2.) Either panel will produce about the same amount of electricity over a year per installed kW. In the opinion of many, Sunpower has no meaningful advantage by any realistic, useful economic measure for the price paid.

          3.) Either system will produce something like 1,600 or so kWh/yr per installed kW. So, to offset 13,000 kWh/yr (And offsetting all of it may not be the most cost effective choice BTW), a back of envelope size might be: 13,000/1,600 = ~ 8.12 kW. Size for your realistic projections, not your dreams and don't oversize.

          4.) Run PVWatts for both panels and use the premium choice for the Sunpower panels, standard choice for the Solarworld.

          5.) Either panel will probably give good service for as long as most folks will own them. The S.P. warranty is overkill and oversold. The S.P. lower annual degradation is difficult if not impossible to verify for a warranty claim and in any case ins't worth - in your case - a 30+ % premium.

          6.) Sunpower's vaunted and touted "highest efficiency" claim is based on [U]area[/U] efficiency - Output/m^2. In terms of what most people care about = $$ paid for the system vs. $$ saved on an electric bill, Sunpower is usually and most often the "lowest efficiency".


          7.) I'd get a few more quotes.

          8.) Choose your vendor with at least as much care as the equipment, or more.

          Thank you for your response.

          I have tried to do the most research and homework as I can because I don't want to spend this large of a chuck of money with out doing my homework.
          I have now received 7 quotes from different companies from the largest (solarcity, sunrun, RGS and 4 local companies) Most expensive was solarcity for 42k and sunrun was lowest at 29k. 3 of the 4 local companies gave me prices for Solar World panels. All systems were between 30-32k for the solar world. Before tax credits.
          After reading lots of reviews, I want someone who will respond to phone calls if I have any issues. And from what I've read it is hard to get the large companies to respond to anything after they get your money.

          From what I've gathered it is not worth the extra money for the SP panels.

          Comment


          • #6
            Originally posted by mrosson View Post
            Thank you for your response.

            I have tried to do the most research and homework as I can because I don't want to spend this large of a chuck of money with out doing my homework.
            I have now received 7 quotes from different companies from the largest (solarcity, sunrun, RGS and 4 local companies) Most expensive was solarcity for 42k and sunrun was lowest at 29k. 3 of the 4 local companies gave me prices for Solar World panels. All systems were between 30-32k for the solar world. Before tax credits.
            After reading lots of reviews, I want someone who will respond to phone calls if I have any issues. And from what I've read it is hard to get the large companies to respond to anything after they get your money.

            From what I've gathered it is not worth the extra money for the SP panels.
            You're welcome.

            More FWIW:

            - On research: Put the horse before the cart. Get a book on residential energy conservation and alternate energy. You'll learn more, better, faster and you'll have better questions that get better answers as a result.

            - Choose your vendor wisely. Negotiate hard but fair. Established electrical contractors who were in business before solar and who have sold/installed solar for at least 5 years are worth some up front premium. You'll have a higher probability of such a vendor returning your communication than those two companies you mention.

            - Those 2 companies usually do leases/PPAs. Is that what you're after ?

            - Read the fine print on any contract.

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

            Comment


            • #7
              Originally posted by mrosson View Post
              Most expensive was solarcity for 42k and sunrun was lowest at 29k. 3 of the 4 local companies gave me prices for Solar World panels. All systems were between 30-32k for the solar world. Before tax credits.
              The systems probably differ somewhat in capacity as well as price. What is the price for each per watt, before tax credits?

              Odd that nobody quoted LG panels, those seem to be the favorites around here.

              Comment


              • #8
                Solar world have 30 years limited warranty on the Sunmodule protect and 25 years warranty of the Sunmodule Plus.
                After 25 years Sunpower claim their modules will still produce 87% and solar world 80 %.
                Sunpower power output a drop of maximum 0.4%/year and Solar World of 0.7 %/year.

                Comment


                • #9
                  Originally posted by solarfrank View Post
                  Solar world have 30 years limited warranty on the Sunmodule protect and 25 years warranty of the Sunmodule Plus.
                  After 25 years Sunpower claim their modules will still produce 87% and solar world 80 %.
                  Sunpower power output a drop of maximum 0.4%/year and Solar World of 0.7 %/year.
                  First off, the panels haven't been around long enough to put much faith in the degradation claim. After 6 + years of some observation, it appears (little more than anecdotally however), that panel degradation is less than advertised for most everyone's panel I sort of keep an eye on. My guess is they're all somewhat conservative.

                  Second, unless you have a way to measure and document solar irradiance, you'll have a hard time verifying a warranty claim.

                  Third, Most folks won't be in their homes long enough to get near a warranty expiration.

                  Lastly, read the fine print. Not all warranties are created equal and none are bulletproof. They're mostly used as marketing tools same as system performance warranties on leases.

                  Comment


                  • #10
                    I don't understand how solar panel warrantees work. I can imagine optimizers or microinverters failing but how do PV modules fail completely? I've read there's some degradation over time, but how exactly do you make and prove a case for a warranty claim and get the manufacturer to send a replacement panel ?

                    Comment


                    • #11
                      Originally posted by awhite View Post
                      I don't understand how solar panel warrantees work. I can imagine optimizers or microinverters failing but how do PV modules fail completely? I've read there's some degradation over time, but how exactly do you make and prove a case for a warranty claim and get the manufacturer to send a replacement panel ?
                      The warranty works just like its written - no more, no less. Read it from the (cynical) seller's point of view and that's what you can expect.

                      In the unlikely event of a complete, non catastrophic failure, where the equipment just craps the bed completely while under warranty, a warranty claim will likely be honored.

                      For a claim dealing with performance, it's usually difficult, if not impossible. I've got a weather station on my roof about 4 ft. or so from the array that also measures and records solar irradiance at 1 min. intervals, and I'm quite sure I'd have an outhouse full of trouble trying to convince anyone with a financial dog in the fight that I have an underperforming system, much less an underperforming panel.

                      Comment


                      • #12
                        I agree with you JPM regarding warranty on my post i copy paste what manufacturer have regarding warranty on their home pages. Couple of years ago I have at a training and John Wiles from Southwest Technology Development Institute , New Mexico State University said they start there in 1980 a testing laboratory and they have ground mount and also roof mount solar modules, but they will no make public results of testing different modules from various manufacturers. 20 years from now we don't know what size panels will be available , if you installed BP 160-180 W 6-7 years ago an one modules it's not performing and kills the whole string it's kind of hard to find something at the same Wattage to replace it.

                        Comment

                        Working...
                        X