Are the sunpower panels a good way to go?

easytimeasytim Solar Expert Posts: 57 ✭✭✭✭
I'm going to be putting up a 4 or 5 kw PV system in Fort Meyers, well more like Pine Island. I'm from St. Louis and bought a 1 ac lot and I'm going to build down there. I think the FPL Florida Power and Light has a rebate of $2.00 a kw right now.

I need a little help with the kind of system I should be buying, I like Sunpower, but I'm open to what others think and other PV panels.

I'm going to have it installed



  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Are the sunpower panels a good way to go?

    The best choice in panels is whatever you can get that fits the bill and the budget. Sunpower panels are as good a quality as any other from what I've heard. Their only quirk is being positive ground. This is usually not a problem for GT systems but doesn't work well with OG systems. SMA inverters actually mention being compatible with positive ground systems, but I'd think twice about trying to use them with a Xantrex XW (for example).

    Come on, GT guys; give the man some input! :p
  • BB.BB. Super Moderators, Administrators Posts: 32,814 admin
    Re: Are the sunpower panels a good way to go?

    Note that Sunpower is a fairly common brand name... There is Sun Power from Germany--which is a very good quality panel (and uses positive grounding for optimum power production).

    From what I understand, they only work through licensed installers and you would probably have difficulties trying to make a do-it-yourself type install.

    There are lots of options from central inverters to distributed inverters (such as Enphase)...

    In general, always work out the size of the system divided by watts... I.e., $30,000 for turnkey install of a 5kW system = $6/watt (range of ~$5-$8+ per watt for turnkey GT system install).

    For cheap, reliable power, Grid Tied is difficult to beat. You can actually break even or even save some money on power. Note, you really need to understand your Power Company's billing polices (i.e, 1 year net metering is usually the best; 1 month net metering is common; and the worst is you buy power at retail and sell to the utility at their wholesale cost of power--usually a money looser).

    Throw in Time of Use billing can really change the equation too. I can buy off peak power for $0.09 per kWH and sell peak solar power for $0.32 per kWH (summer, Mon-Fri, Noon-6pm). I can shift much of my power use to off peak usage and end up getting 3x the "money" from my solar panels for off peak use. This is common in California (and, I think TOU is required for solar GT), but in Florida, probably not.

    And, in the end, we start at the beginning--Do anything you can to reduce power usage (insulation, CFL/LED lighting, double pane windows, more insulation in roof, energy star appliances, most efficient A/C system you can, etc.)... For hot climates, you spend money to bring power into the home (fridge, computers, Entertainment systems, etc.) and then pay again for the A/C system to move the heat outside.

    Also, you may want to look at Heat Pump Hot Water--Easily 2x as efficient as the old electric hot water heater, and may be cheaper than natural gas/propane. Plus the Heat Pump Hot Water system will cool the garage and dehumidify too (for "free").

    A GT system will not give you "emergency/backup power"... You will need to do something else if that is needed... If your power outages are not too long, typically a backup AC Genset will be your most cost effective solution.

    If you want solar backup power too--That will cost a lot more (2-4x the price of GT) for the Hybrid Inverter + battery bank + charge controllers + battery replacement every 7-15 years or so...

    And, remember that, for pretty much all electronics, expect around a 10 year life and have the savings to replace them when needed. You may have a failure earlier and can have the device repaired... But after 10 years--it gets very difficult to find repair facilities and parts to do the repairs (plus you may have subsequent failures from your 10+ year old system anyway).

    Find a reliable installer and supplier of your equipment (good luck with that in these financial times). I am on my second solar array and third inverter after ~6 years. Fortunately, my installer is still around, and the component vendors have pretty much stepped up to support the warranties (and my working GT inverter was upgraded out of the 5 year warranty for no-charge).

    Also, look very closely at the rebates/credits you may receive... For example, the Florida rebate is probably $2/watt (not $2 per kW) installed. However, it seems to go very quickly, leaving people to collect the money "next year"--And that is always "maybe next year".

    The Federal 30% tax credit only works for you if you pay federal taxes--and can carry over for a few years.

    Do not look at solar GT power as an "investment"... It rarely is, especially in "cheap power" states. Conservation usually has a better rate of return--so look there first.

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • solarixsolarix Solar Expert Posts: 713 ✭✭
    Re: Are the sunpower panels a good way to go?

    All but a few PV makers offer 25 year warranties, so reliability is not an issue even though some modules (like Sunpower) have better efficiency. You pay a lot for the more efficient modules but they are not any more reliable. Actually, I think the warranty issue comes down to - will that company be still around in 25 years? A lot of them won't to be sure. Some of the best old names in PV modules are not staying competitive and may be the first to go as prices continue to fall. Brands like Trina, Canadian Solar, Suntech, Solon, Sun, (and others) are the ones pushing the volume/price envelope and therefore will be the long term winners. So it really comes down to the $/watt you pay. Buy a brand that is trying to get its volume up and up and up so it can get its price/watt down - down - down, and you should have a good deal as well as reliability.

    Unless you are constrained with not enough roof area, you don't need the high-efficiency modules.
  • Shane JacksonShane Jackson Solar Expert Posts: 49
    Re: Are the sunpower panels a good way to go?

    Do you want grid tied or off grid?

    I have been researching solar for over 10 years. Every time I build a new house I research solar and have always came to the same conclusion.... It does not make economical since. Until recently that is, with the price of panels dropping below the $1/watt mark (well laminates that is). If you ave the time and skills needed to install junction boxes and build frames for the laminates you can get a nice system for a lot less than you use to could.

    One thing I am not sure of is if you can use the laminates on a grid tied system or not. For me it doesn't matter as I plan on putting in an off grid system.

    Grid tied would be cheaper as you don't have to buy charge controllers or batteries and the inverters are cheaper. However you have to go thru all the red tape which can add to the cost and can be a real pain. Also if the grid goes down, there you sit with no power..... that is unless you get a grid tied inverter charger. But those are very expensive and you still have to buy batteries. In that case you would probably end up higher than an off grid system.

    The only disadvantage of an off grid (for me anyways) is you can not get the utility credits... however here in NC it seems they are not that great. You have to enter a contract with your utility to sell them all the power you produce at 1/2 the cost you pay and then you get a "green" credit for about the cost of the power produced. For me it was .145 per kw produced credit, however .10 is funded by nc green power. Which is a publicly funded entity that basically sells carbon credits. My problem with the whole deal is you have to sign a 15 year contract with your utility to sell to them at .045/kw and the nc green $ is not guaranteed. If they don't have enough public contributions you don't get your incentives... I can just see a few years in the green power incentive disappearing, then you are stuck selling your power at 1/2 what you buy it back for..... NO THANKS

    Sorry to ramble on.....

  • rollandelliottrollandelliott Solar Expert Posts: 834 ✭✭
    Re: Are the sunpower panels a good way to go?

    I'm about 1.25 hrs away from you near charlotte, NC. Send me your ph# via private message and we can talk about solar and you can see my 6kw set up. I might have some good ideas for you as well.

    If you have access to grid power that is the cheapest way to go and payback can be as little as 6 or 7 years.
  • PhotowhitPhotowhit Solar Expert Posts: 5,910 ✭✭✭✭✭
    Re: Are the sunpower panels a good way to go?
    easytim wrote: »
    I'm going to be putting up a 4 or 5 kw PV system in Fort Meyers, well more like Pine Island. I'm from St. Louis and bought a 1 ac lot and I'm going to build down there. I think the FPL Florida Power and Light has a rebate of $2.00 a kw right now.

    If this is a secondary residence the federal 30% tax tredit only works if you don't rent it out, I have no Idea if thats for the year installed or for the life of the unit, I would hope if you change your mind after a year or 2 you wouldn't be penalized, but these are "burro"crats we're talking about...

    I understand some areas of Florida have just tons of hoops to get through, I think "Solar Guppy"? is an installer in in Tampa area and may even extend that far, I'd PM him (I hope I've got the right guy)and ask for a recomendation for local installers. The right installer can make a lot of difference, does the local inspector like WEEB or will he make you install lay in lugs even with WEEB system in place? or better yet does the local inspector like sprinkles, jelly filled or a good dunking donut?
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former, 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Solar GuppySolar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: Are the sunpower panels a good way to go?

    I'm not an installer and never have been ( look at my signature )

    On what panel to select, that's kind of putting the cart before the horse. You first need to figure out whom will install the system and whom will design it. In Florida you have to meet the 120mph wind codes, this requires, no exceptions a State Licensed PE ( professional engineer )

    My personal opinion is get whatever is the lowest cost UL listed panel ... you can find them a plenty for half the price of the "SunPower" brand which is manufactured by a Californian company not the relabeled stuff from Miami that calls some of it in house brand "Sun"
  • sub3marathonmansub3marathonman Solar Expert Posts: 300 ✭✭✭
    Re: Are the sunpower panels a good way to go?
    I'm not an installer and never have been ( look at my signature )

    While Solar Guppy's statement is true, I can say that without his help, knowledge, patience, and sometimes chagrin at my worrying about every trivial detail, I'm not sure if my system would be installed yet.

    Solar Guppy, along with many others here, are greatly appreciated for the time they spend helping.
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