Hello from the Sunshine State

FL SUNFL SUN Solar Expert Posts: 94 ✭✭✭✭
Just wanted to introduce myself as I am new to this forum. I am a solar and energy efficiency advocate, and thoroughly enjoy working on anything electrical or mechanical, especially if it has to do with solar, and heating water or "making energy".

I just recently passed the FL state certified solar contractor's exam, and am working to finalize my licensure through the state. I am currently a mechanical contractor, and have been involved with building envelope science and providing people with ways to help reduce their utility consumption while providing them comfort.

I am looking forward to the opportunities of providing others a means to empower themselves by supplementing their electrical and domestic hot water from the sun. I have a solar DHW set-up that provides most or all of my hot water, and am a firm believer that solar DHW should be incorporated as a requirement in residential and commercial new construction in the future.

We are gearing up for our first grid tied 6kw PV system which will be arriving by freight tomorrow. We will be using 32 Evergreen ES-190 modules with a Sunny Boy 6000U inverter. For this first "show-and-tell" system, we will be using an electrical contractor so the customer will be eligible get their $20,000.00 state incentive. I have already found out that everything goes through the state's FSEC certification program, and am also in the process of getting this particular system approved.

I will have many questions, and as the ball gets rolling, look forward to sharing some experiences and pics with you all.

Comments

  • Solar GuppySolar Guppy Solar Expert Posts: 1,973 ✭✭✭
    Re: Hello from the Sunshine State

    There is no need to deal with FSEC. The rebate program has no requirements that a system meet the approval of FSEC, FSEC feels otherwise as its the only reason for their funding and usefulness. Save your money for other expenses
  • FL SUNFL SUN Solar Expert Posts: 94 ✭✭✭✭
    Re: Hello from the Sunshine State
    There is no need to deal with FSEC. The rebate program has no requirements that a system meet the approval of FSEC, FSEC feels otherwise as its the only reason for their funding and usefulness. Save your money for other expenses

    Interesting....... Could you elaborate on that some more?

    I am under the impression that the state will be looking for a "certification approval number" for grid tied systems installed in FL. Or is it the power company looking for it to allow interconnection to their grid? It is an electric co-op, and they seem to be allowed to somewhat make their own rules when it comes to net metering and connection requirements.
  • Solar GuppySolar Guppy Solar Expert Posts: 1,973 ✭✭✭
    Re: Hello from the Sunshine State

    Read here and look at the application, no FSEC approval is required

    http://www.dep.state.fl.us/energy/energyact/solar.htm

    http://www.dep.state.fl.us/energy/energyact/files/solar_rebate_app.pdf


    Background:

    FSEC, in 1976 got a law passed that said anything solar sold in Florida has to have there approval, but there is no enforcement and no one pays attention to this.

    When the rebate program started two years ago, FSEC started a campaign to require that anything that got rebates would need there stamp of approval even though they hadn't approved anything in 3-4 years an NONE of the manufactures were to give them stuff for what was essentially retesting already UL approved parts.

    The FL State DEP which run the rebate program got a lawyer review of the FSEC position and stated that the recent rebate law made NO mention of the FSEC requirement and since then they have been completely ignored.

    FSEC, only for self sufficiency reasons tells anyone who will listen they MUST be included but the truth is they have NO part of the FL rebate program

    I did a 5KW system 2 years ago and have many discussions with the program head on this topic. All you need is a FL licensed installer OR a Master Electrician to sign off, not both. You also need Utility agreement and City/County permit signed off.

    Keep in mind there is no money this year, applications are being accepted for NEXT years funds, which at this point have NOT been approved by the state legislators and with a 1 billion+ short fall is a complete gamble that solar rebate will be funded for 2009-2010 fiscal year
  • solarteksolartek Solar Expert Posts: 69 ✭✭✭✭
    Re: Hello from the Sunshine State

    While what everything Solar Guppy is saying is true, sometimes having the system FSEC certified "helps" with utility interconnection or permitting. Where I am located in Orlando, the local utility hires FSEC to do an inspection of the system prior to the interconnection. With the system already FSEC certified, the inspections tend to run smoothly. And when I have submitted permits to the city, one of the questions always asked is "What is the system's FSEC certification number?". It is NOT required by the city building department and I know other installers who do not get their systems certified. For me, it is a cost of doing business so I submit them.

    Scott.
  • FL SUNFL SUN Solar Expert Posts: 94 ✭✭✭✭
    Re: Hello from the Sunshine State

    Thanks SG for that information. I thought it seemed redundant to have more hands in the pot regarding this matter.

    I'm going to have to discuss this with the electric co-op rep as he seems quite certain to expect an approved FL cert number, line drawings, and the like from FSEC.
  • FL SUNFL SUN Solar Expert Posts: 94 ✭✭✭✭
    Re: Hello from the Sunshine State
    solartek wrote: »
    While what everything Solar Guppy is saying is true, sometimes having the system FSEC certified "helps" with utility interconnection or permitting. Where I am located in Orlando, the local utility hires FSEC to do an inspection of the system prior to the interconnection. With the system already FSEC certified, the inspections tend to run smoothly. And when I have submitted permits to the city, one of the questions always asked is "What is the system's FSEC certification number?". It is NOT required by the city building department and I know other installers who do not get their systems certified. For me, it is a cost of doing business so I submit them.

    Scott.


    Another good point. Since this grid tied concept (in our location) is in its infancy, I see many local governing authorities will choose to rely on the FSEC certification to feel "comfortable" with tying into their grid. In the FL panhandle, solar education and application is in the dark ages just beginning to get tapped.
  • solarteksolartek Solar Expert Posts: 69 ✭✭✭✭
    Re: Hello from the Sunshine State
    FL SUN wrote: »
    Another good point. Since this grid tied concept (in our location) is in its infancy, I see many local governing authorities will choose to rely on the FSEC certification to feel "comfortable" with tying into their grid. In the FL panhandle, solar education and application is in the dark ages just beginning to get tapped.

    FL SUN,

    Are you in the panhandle area? If so, then I have a concern about your proposed design. I'm assuming you're planning 2 strings of 16 panels each? It looks to me that your Voc at cold will be dangerously close to the 600V max value. What is your coldest expected temperature for the system location?

    Scott.
  • Solar GuppySolar Guppy Solar Expert Posts: 1,973 ✭✭✭
    Re: Hello from the Sunshine State

    According to the Xantrex Calculator, 16 modules is marginal in the low side due to 95 degree ambient I Selected

    http://www.xantrex.com/support/gtsizing/index.asp?lang=eng#calculator
  • solarteksolartek Solar Expert Posts: 69 ✭✭✭✭
    Re: Hello from the Sunshine State
    According to the Xantrex Calculator, 16 modules is marginal in the low side due to 95 degree ambient I Selected

    http://www.xantrex.com/support/gtsizing/index.asp?lang=eng#calculator

    I get minimum Vmp = 344.54V at 95F for 16 Evergreen ES-190 panels. That's marginal?
  • Solar GuppySolar Guppy Solar Expert Posts: 1,973 ✭✭✭
    Re: Hello from the Sunshine State

    Question would be which 190 module? ... the ES-A-190-B are 12V nominal panels the ES-190-B are 18V nominal and yes, that would be limited to 14 in a string
  • FL SUNFL SUN Solar Expert Posts: 94 ✭✭✭✭
    Re: Hello from the Sunshine State
    solartek wrote: »
    FL SUN,

    Are you in the panhandle area? If so, then I have a concern about your proposed design. I'm assuming you're planning 2 strings of 16 panels each? It looks to me that your Voc at cold will be dangerously close to the 600V max value. What is your coldest expected temperature for the system location?

    Scott.

    Yes - 2 strings of 16. Our coldest temperature by the time the sun is shining directly on the panels would be around 40 deg F. If these panels were to be mounted on a tracker with two axis control, Voc would be close to threshold in the early morning sun on a freezing morning. Since these will be roof mounted and non-tracking, early morning sun at a glancing angle should not pose an issue. Professional input from experience is very welcome here on this subject.

    Sizing the panels to allow for very hot summer roof temps is obviously an important factor. I would expect to see 120 to 180 deg F (or more) ambient temps around these modules on a roof.

    My main concern: It would be horrible to think your system is pumping juice into the grid on a hot sunny day, when in reality your inverter is in standby mode waiting for your PV voltage to rise when the panels cool down.
  • solarteksolartek Solar Expert Posts: 69 ✭✭✭✭
    Re: Hello from the Sunshine State

    OK. I was assuming the Spruce Line (ES-190-RL/SL) which Evergreen just stopped producing this quarter.

    Actually neither the ES-A-190 and the ES-B-190 in a 16 panel string would be a good match for the SB6000US since it's MPPT tracking range is 250V-480V and at 95F the minimum Vmp would be 227.71V and 225.77V respectively.
  • FL SUNFL SUN Solar Expert Posts: 94 ✭✭✭✭
    Re: Hello from the Sunshine State
    Question would be which 190 module? ... the ES-A-190-B are 12V nominal panels the ES-190-B are 18V nominal and yes, that would be limited to 14 in a string

    The modules in this design will be the ES-190-SL. Not the ES-A-190's.

    I used the SMA Sunny Boy string sizing program they have. I also looked at the Xantrex and Solectria sizing charts for an "average" of data from those manufacturers as well.

    http://america.sma.de/newstringsizing.aspx

    According to their chart, Voc @ 32 deg F for 16 in a series is 569 volts. Min peak power voltage @ 131 deg F is 333 volts. This configuration should be acceptable - shouldn't it?
  • FL SUNFL SUN Solar Expert Posts: 94 ✭✭✭✭
    Re: Hello from the Sunshine State
    solartek wrote: »
    OK. I was assuming the Spruce Line (ES-190-RL/SL) which Evergreen just stopped producing this quarter.


    What's the skinny with the end of production on these panels?
  • BB.BB. Super Moderators, Administrators Posts: 32,021 admin
    Re: Hello from the Sunshine State
    solartek wrote: »
    I get minimum Vmp = 344.54V at 95F for 16 Evergreen ES-190 panels. That's marginal?

    I am guessing that you are using the formula based on 77F to 95F for Vmp... In reality, the panel in full sun on a 95F day, little wind, and perhaps mounted near flat to a slopped roof will get a lot hotter...

    For example... the ES-A-190 has a Vmp of 17.4 volts.

    At 95F, Xantrex will estimate the panel voltage will be Vmp=14.232

    The temperature coefficient for the above panel is: -0.0704 V/°C

    [email protected] = Vmp + TC(Tcell-Tstc)

    Working the above equation backwards, Xantrex assumes that a panel will run at +45C with respect to ambient (or +81F).

    So, your 95F panel may actually run as hot as 95F+81F=176F on a sunny, no wind, worst case mounting (low to roof).

    So, 16 panels @ 176F in series will be, Vmp worst case of:

    [email protected] ~ 16*14.232v=227.71 volts

    I don't know much at all about the Sunny Boy 6000US inverter, but from their website:
    Peak Power Tracking Voltage 250 – 480 V
    ...
    PV Start Voltage (adjustable) 300 V
    So, it would appear (if using ES-A panels), that 16 in series may not work well in very hot weather (depending on other conditions).

    -Bill

    PS: You are using different panels--so ignore my details--but the basics still apply
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • solarteksolartek Solar Expert Posts: 69 ✭✭✭✭
    Re: Hello from the Sunshine State
    FL SUN wrote: »
    The modules in this design will be the ES-190-SL. Not the ES-A-190's.

    I used the SMA Sunny Boy string sizing program they have. I also looked at the Xantrex and Solectria sizing charts for an "average" of data from those manufacturers as well.

    http://america.sma.de/newstringsizing.aspx

    According to their chart, Voc @ 32 deg F for 16 in a series is 569 volts. Min peak power voltage @ 131 deg F is 333 volts. This configuration should be acceptable - shouldn't it?

    The question is really what is the minimum and maximum temperature the array will see. Is the minimum really 32F? If you follow the advice of the SMA sizing tool, you enter the zip code where the array will be located and use the lowest and highest record temperatures from the resulting web page. Then calculate Voc max and Vmp min. What do you get then?
  • solarteksolartek Solar Expert Posts: 69 ✭✭✭✭
    Re: Hello from the Sunshine State
    FL SUN wrote: »
    What's the skinny with the end of production on these panels?

    I don't anything other than the note on their web site for this product stating that production will end Q1 2009.
  • FL SUNFL SUN Solar Expert Posts: 94 ✭✭✭✭
    Re: Hello from the Sunshine State
    solartek wrote: »
    The question is really what is the minimum and maximum temperature the array will see. Is the minimum really 32F? If you follow the advice of the SMA sizing tool, you enter the zip code where the array will be located and use the lowest and highest record temperatures from the resulting web page. Then calculate Voc max and Vmp min. What do you get then?

    Coldest record temp in our area is 4 degrees, highest is 104 degrees.

    At 5 degrees, Voc = 596
    At 107 degrees, Vmp = 436

    Voc is very close to threshold - too close for comfort. But those cold temps never happen when the sun shines. By the time the sun wakes up the world here, we rarely ever see below freezing temps after 8:00 AM on. What is "the rule of thumb" concerning this issue?

    BB hit the nail on the head with the high ambient roof temps. My greatest fear is drop-out due to high temp panel issues. Again very easily around 180 degrees with no breeze.
  • BB.BB. Super Moderators, Administrators Posts: 32,021 admin
    Re: Hello from the Sunshine State

    Also, double check the SMA--Sunny Boy results too... Last year (or so), the website was not calculating/displaying the power/Vmp values correctly against the inverter's limits.

    It is probably fixed by now--but better safe than sorry.

    Notice that they mark in "RED" any Vmp's that are below 300 VDC (inverter will not start if lower?). And >550 VDC in yellow (no longer MPPT????).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • solarteksolartek Solar Expert Posts: 69 ✭✭✭✭
    Re: Hello from the Sunshine State
    FL SUN wrote: »
    Coldest record temp in our area is 4 degrees, highest is 104 degrees.

    At 5 degrees, Voc = 596
    At 107 degrees, Vmp = 436

    Voc is very close to threshold - too close for comfort. But those cold temps never happen when the sun shines. By the time the sun wakes up the world here, we rarely ever see below freezing temps after 8:00 AM on. What is "the rule of thumb" concerning this issue?

    BB hit the nail on the head with the high ambient roof temps. My greatest fear is drop-out due to high temp panel issues. Again very easily around 180 degrees with no breeze.

    My designs tend to be very conservative so I would use the 4F which makes the Voc at cold too close to 600V. So I wouldn't use 16 panel strings. The Vmp at hot is well within the range of the MPPT tracking window of the SB6000US so that is not a cause for concern for me.

    Others may have other opinions, of course.


    Scott.
  • Solar GuppySolar Guppy Solar Expert Posts: 1,973 ✭✭✭
    Re: Hello from the Sunshine State

    You will be fine with 16 panels, VOC values are in peak full sun, 1000/watt-meter-squared

    In reduced irradiance, the VOC drops, look at any solar panel data sheet, you won't be anywhere near 600V even at 4F in Florida, once the sun shines even a little bit, the panels will quickly rise in temperature

    I have 15 in series and barely make it into the mid 400's ( volts ) in the cold weather
  • FL SUNFL SUN Solar Expert Posts: 94 ✭✭✭✭
    Re: Hello from the Sunshine State

    Thanks for all the input everyone.
  • rollandelliottrollandelliott Solar Expert Posts: 834 ✭✭
    Re: Hello from the Sunshine State
    solartek wrote: »
    .....sometimes having the system FSEC certified "helps" with utility interconnection or permitting. Where I am located in Orlando, the local utility hires FSEC to do an inspection of the system prior to the interconnection. With the system already FSEC certified, the inspections tend to run smoothly.
    Scott.

    Sounds typical of local governments, each permitting office is probably different. If you are unlucky you'll get someone really anal that wants FSEC certification, even though by glancing at their history of panel testing you can see they are very behind in what is new and pretty much ignored.
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