New here with some questions

System
System Posts: 2,511 admin
in General Solar Power Topics #1
I have a company coming out today to go over an install by the name of Arizona Solar Power, they say they use a 225 watt panel is the world’s most efficient all-black solar panel. Which has a rated efficiency of 18.1%, that sounds pretty good to me. I'm just wondering if anybody has used this company and are these panels good? Thanks...
· Share on Twitter

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #2
    Re: New here with some questions

    In general--more efficient panels cost more money per watt vs the lessor efficient panels.

    For the customer, do a $$$/watt calculation. If your roof (or other area) is space limited, then you may want to pay a premium for higher efficiency panels (more power in the same amount of space).

    Depending on the specific panel manufacturer, there are some issues that can arise (one vendor requires positive ground for their panels--and that is just an option when the inverter is ordered. Others may "use" reflected light from underneath the panels for a little additional power, and others yet may use unproven reliability amorphous+crystalline cells).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
    · Share on Twitter
  • System2
    System2 Posts: 6,290 admin
    #3
    Re: New here with some questions

    Thanks Bill, I have a good size roof to allow a lot of room for the panels, my main concern is that I have a 5000 sf home with the electric running up to 1200 this month. So with that amount I'm guessing that I need to have some good size panels installed.
    · Share on Twitter
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    #4
    Re: New here with some questions

    It better for the customer to buy on price per watt, not watt per square foot ( efficiency )

    The SunPower panels ( the ones you describe ) are way over hyped, yes they are the most efficient per square foot but another panel that might be say 2 inches wider for the same wattage might cost half what a sunpower panels gets.

    Get a quote for a system using Sunpower and EverGreen panels, they will deliver the exact same wattage, but should be a significant difference in materials cost
    · Share on Twitter
  • System2
    System2 Posts: 6,290 admin
    #5
    Re: New here with some questions

    Thanks, I will asked them about these two panels. They will be here within the hour...
    · Share on Twitter
  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #6
    Re: New here with some questions

    Joe,

    One other important point... CONSERVATION.

    Have you reviewed your power usage and done pretty much everything you can regarding conservation (insulation, more insulation, double pane vinyl windows, turning things off, energy star appliances, smaller laptop vs desktop computers, new more efficient A/C system, using alternative methods for making hot water--if using electricity, etc.)?

    At best, Solar Grid Tied power is a wash with existing power rates for much of the country. And is some places (like California) when combined with Time of Use metering (shifting power usage to non-peak times--especially in summer months where power can be $0.30-$0.60+ per kWhr vs the $0.10 or so per kWhr that the rest of the country pays) can really save money.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
    · Share on Twitter
  • System2
    System2 Posts: 6,290 admin
    #7
    Re: New here with some questions

    Just got hit with a 23.82 unit that will cost me 113 grand out of pocket... I sent them back to the drawing board.. I think like you said, I might change out the three roof top units which are old first and see where I'm stand and go from there first.
    · Share on Twitter
  • Windsun
    Windsun Solar Expert Posts: 1,164 ✭✭
    #8
    Re: New here with some questions

    Every time I read about those panels, it seems like the hype meter goes even higher.

    On their spec sheet they claim

    More Power:
    Delivers up to 50% more power per unit area than conventional solar panels

    And I have heard of some dealers claiming that they will provide "40 to 50% more power than conventional panels". What they fail to mention is that they are using some unknown 165 watt panel as the example of "conventional".

    But if you do the math, it just is not physically possible. For example, compared to a standard Kyocera KD210 I come up with about a 10 to 12% best case scenario for the same square footage, and the Kyocera and Evergreen panels have a better temperature coefficient.

    · Share on Twitter
  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #9
    Re: New here with some questions

    That is $4.74 per watt installed.

    $4.74/0.70 = $6.78 per watt pre-Fed Tax rebate...

    My cost for a 3.5 kW (3.0 kW CEC rated) when panels where in short supply and $5+ per watt vs the near $3 per watt you can now find:

    $29k/3.0 kw= $9.67 per kW (before $2.50 and 30% Fed credit)
    $21k/3.0 kw= $7.00 per kW (after rebates/credits)

    $5.xx per month electric bill (minimum bill) with $250-$300+ unused credit per year.

    Have they go other rebates/credits in there?

    What kind of rate plan(s) do you have available (flat, time of use, seasonal, 1 year net metering, etc.)?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
    · Share on Twitter

Categories