Solar Panel

edanthonyedanthony Registered Users Posts: 7
:D
Good Day Folks!

Asking for some advice for my project. To begin with I'm preparing materials to build a 5000 watts solar panel. This is intended for my AC unit ( 3500 watts). I wonder if this solar output would have enough power to supplement the sudden surge of current produce by the motor compressor which is 500% more than its rated operating amperage.I'm afraid it will damage the solar panel and the inverter as well. By the way I plan for an off grid system, the solar output goes
directly to the inverter without battery.

Thanks for your effort.
Anthony

Comments

  • BB.BB. Super Moderators, Administrators Posts: 30,178 admin
    Re: Solar Panel

    Do you have a link to the inverter you want to use?

    I do not know of any off grid capable inverter that will operate reliably operate without a battery bank.

    Solar panels have zero surge capabilities as they are current source devices.

    Lastly, a large do it yourself solar array, tend to be unreliable and fire hazards... Building a small panel to learn can be interesting. But making your own panels for a large solar array is usually not cost effective.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490mike95490 Solar Expert Posts: 8,653 ✭✭✭✭✭
    Re: Solar Panel

    Don't spend any $$ yet. Wait and get answers first.

    As you proposed, it will not work.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Solar Panel

    A couple of threads you should read through that deal with the same plan:

    http://forum.solar-electric.com/showthread.php?t=11824

    http://forum.solar-electric.com/showthread.php?t=11787
  • ggunnggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Solar Panel
    edanthony wrote: »
    :D
    Good Day Folks!

    Asking for some advice for my project. To begin with I'm preparing materials to build a 5000 watts solar panel. This is intended for my AC unit ( 3500 watts). I wonder if this solar output would have enough power to supplement the sudden surge of current produce by the motor compressor which is 500% more than its rated operating amperage.I'm afraid it will damage the solar panel and the inverter as well. By the way I plan for an off grid system, the solar output goes
    directly to the inverter without battery.

    Thanks for your effort.
    Anthony
    Welcome to the world of solar power. As others have said, you have a lot of homework to do before you lay the first nickel down. What you propose is not doable as you propose it. You can't run a 120/240VAC system off grid system without batteries, and a 3500W A/C system is going to take a lot of them.

    Why are you wanting to run off grid? If the grid is available, building an off grid system to power that A/C is going to cost at least ten times what it would cost just to power it from the grid.
  • waynefromnscanadawaynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Solar Panel

    If you go ahead and build your 5000 watt solar panel, hind sight will have you asking "why did I ever even consider trying such a thing :cry:
    Unfortunately I'm not joking. :cry:
  • BB.BB. Super Moderators, Administrators Posts: 30,178 admin
    Re: Solar Panel

    Ask Wayne about DIY projects:
    Quote:
    Originally Posted by BB.
    "energetic disassembly"

    -Bill


    Haha I love that term. Perfectly describes my first attempt at a "home made" wind turbine. Spent weeks forming a beautiful 14 foot long blade of wood. Was shocked by the power it produced. Then I came home one wk-end and found a six foot portion of the blade sticking out of the barn roof, where it had been driven in like a giant knife.

    Except for a one foot long tip, the rest of the blade was never seen again.
    Now I know it had been subjected to "energetic disassembly". Haha
    Wayne
    If I remember correctly, he did find some more prop in the pond a few years later during a drought.

    And wind turbines actually do lend themselves a bit better to DIY vs solar PV panels.

    Solar Thermal (hot water, heating, etc.) can also be a very good project and it will save you money too with some of the quickest payback of any solar projects (short of conservation).

    -Bill ;)
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • waynefromnscanadawaynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Solar Panel
    BB. wrote: »
    Ask Wayne about DIY projects:



    If I remember correctly, he did find some more prop in the pond a few years later during a drought.

    And wind turbines actually do lend themselves a bit better to DIY vs solar PV panels.

    Solar Thermal (hot water, heating, etc.) can also be a very good project and it will safe you money too with some of the quickest payback of any solar projects (short of conservation).

    -Bill ;)

    Hahaha Yes man, early last spring the nearby lake was WAY down, lowest in probably 40 years, and lo and behold, while walking along the new-found beach, about 100 or more feet from the normal shoreline, was something sticking up out of the mud that looked very familiar. Actually it was the green pant still on it that caught my eye. Just could not believe what I was seeing! About a 3 foot length of one of the tips of the blade, stuck in the bottom of the lake where apparently the water had preserved it for almost 30 years! Talk about the past coming back to haunt you! Hahaha
    And re the solar hot water - - Bill is right there too! I built my own hot water panel about 8 years ago now (before the price of copper went through the roof) and I've been EXTREMELY happy with it! Two years ago one of the solder joints in the lower header developed a leak, fixed that and no more problems, just all kinds of free hot water! A huge success story, very unlike the wind turbine. We've not had much sun the last few days and as I look over my shoulder at the readouts, the top of my 60 (Cdn) gallon tank is at 132*F and the bottom is at 122*F. For the first while it was in operation, I actually felt guilty, like I was stealing from Nova Scotia Power, but in time that wore off and now I just take it all for granted.:p:p
  • ggunnggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Solar Panel
    Hahaha Yes man, early last spring the nearby lake was WAY down, lowest in probably 40 years, and lo and behold, while walking along the new-found beach, about 100 or more feet from the normal shoreline, was something sticking up out of the mud that looked very familiar. Actually it was the green pant still on it that caught my eye. Just could not believe what I was seeing! About a 3 foot length of one of the tips of the blade, stuck in the bottom of the lake where apparently the water had preserved it for almost 30 years! Talk about the past coming back to haunt you! Hahaha
    How far was this from the site of the "disassembly"?
  • RCinFLARCinFLA Solar Expert Posts: 1,280 ✭✭✭
    Re: Solar Panel

    Don't build your own PV panels. You will regret it. They are not at all like building a solar hot water heater and you can buy commercial built PV panels for about the same amount of money as you will spend on components to build your own.

    No, they will not supply startup surge (unless you terribly oversize the PV wattage). My Lenox central draws 3250 watts run power (13.5 amps @ 240vac) and has a 400 msec 25,000 VA startup surge (120 amps with some wiring voltage drop). The scroll compressors used by Lenox have a very high startup surge. They are like the Wankel engine equivalent for A/C compressors.

    No, you won't damage PV panel due to surge. They are illumination based current sources. You can short them out and there is no damage.

    There are a couple of air conditioner manf. that offer PV assist accessories. (Lenox for one). They are primarily a marketing gimmick.

    They are basically grid tie inverters that operate in parallel with grid supply.

    If you go to trouble of having PV panels and GT inverter you might as well connect the GT inverter direct to AC mains, not just the air conditioner. When air conditioner is off you will gain the benefit of offsetting the power consumed by your other loads.
  • waynefromnscanadawaynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Solar Panel
    ggunn wrote: »
    How far was this from the site of the "disassembly"?

    Haha About 500 feet. The vast majority of the blade has never been seen again. :p
    Very lucky no one was around when that happened for sure!
  • ggunnggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Solar Panel
    Haha About 500 feet. The vast majority of the blade has never been seen again. :p
    Very lucky no one was around when that happened for sure!
    It's too bad you weren't video monitoring the turbine when it disassembled itself. You'd have gotten a lot of hits on YouTube.
  • techntrektechntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: Solar Panel

    Well, 30 years ago, not so much. tongue.gif
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • Dr. StrangeloveDr. Strangelove Solar Expert Posts: 49
    Re: Solar Panel
    edanthony wrote: »
    Asking for some advice for my project. To begin with I'm preparing materials to build a 5000 watts solar panel. This is intended for my AC unit ( 3500 watts).

    I'm guessing that you mean that you are building a solar array capable of 5 kW output. A single 5kW panel would be extremely unwieldy. And, as others have pointed out, a very poor DIY choice.
    I wonder if this solar output would have enough power to supplement the sudden surge of current produce by the motor compressor which is 500% more than its rated operating amperage.

    No. And I assume that you mean "sudden surge of current demanded by the compressor motor". Where do you expect the additional 12.5 kW to come from? Solar cells simply transform available sunlight into electricity.
    I'm afraid it will damage the solar panel and the inverter as well.

    You won't damage the solar cells, but your inverter is likely to shut down. To the best of my knowledge, there is no 5 kW inverter that is surge rated to 350%. 200% maybe, but not 350%. And even if you could find an inverter willing to endure that abuse, you're likely to damage your compressor trying to start it without the necessary current surge as the voltage sags.
    By the way I plan for an off grid system, the solar output goes directly to the inverter without battery.

    Yeah, that's pretty much never going to work. Assuming you surmount the other insurmountable problems, how well do you expect the compressor to handle the reduced output from clouds? Rain? Or night? Generally, "off grid" means "batteries".

    Just some thoughts in no particular order: your A/C sounds massive at 3.5kW - are you operating a meat storage facility? Second, your compressor starting transients are not amenable to a reasonable off-grid solution - perhaps you could upgrade to a split-air system that is less grunty/brute-forcish in a 1950's kind of way and far more efficient. Third, for your current A/C you will need batteries, about 50 kWh worth, a couple of PV charge controllers, and a 10kW inverter.
    • 50 kWh to handle the 5 kW sourced from the array at approximately a C/10 rate.
    • For a 48 V battery system, you have a 100 A charge rate which generally means 2 charge controllers; any lower voltage gets out of hand quickly (12V is 400A!).
    • And a 10kW inverter (or set of inverters) should handle your 17.5 kW motor transients, but will likely not be operating at its most efficient point with a 3.5 kW load.

    Hope that helps.
  • ggunnggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Solar Panel
    I'm guessing that you mean that you are building a solar array capable of 5 kW output. A single 5kW panel would be extremely unwieldy. And, as others have pointed out, a very poor DIY choice.
    Not to pick nits, but very often people use the term "panel" when they really mean "module". A panel is a group of modules wired together and physically attached to each other to make a field installable unit (per NEC2008 ). Of course a 500W panel, even by its NEC definition, would still be very unwieldy. The OP undoubtedly does indeed mean a 5000W array.
  • BB.BB. Super Moderators, Administrators Posts: 30,178 admin
    Re: Solar Panel

    Edanthony is probably out of Eastern Europe, so is probably looking to save money with a do it your self project.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490mike95490 Solar Expert Posts: 8,653 ✭✭✭✭✭
    Re: Solar Panel
    ggunn wrote: »
    Not to pick nits, but very often people use the term "panel" when they really mean "module". A panel is a group of modules wired together and physically attached to each other to make a field installable unit (per NEC2008 ). Of course a 500W panel, even by its NEC definition, would still be very unwieldy. The OP undoubtedly does indeed mean a 5000W array.

    Module, is a group/assembly of somethings, individual PV cells are the lowest denominator, NEC may be wrong here, I've not looked it up.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • ggunnggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Solar Panel
    mike90045 wrote: »
    Module, is a group/assembly of somethings, individual PV cells are the lowest denominator, NEC may be wrong here, I've not looked it up.
    The NEC wrong? NEVER!!! ;^)
  • BB.BB. Super Moderators, Administrators Posts: 30,178 admin
    Re: Solar Panel

    [wrong thread, wrong poster. Sorry. -Bill B.]

    Ease up guys... This guy's English is only a little worse than mine--And this is the only language I know. :cry:

    NEC 1/2 way around the world--Hard enough to get it right in the US. :roll:

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Solar Panel
    BB. wrote: »
    Edanthony is probably out of Eastern Europe, so is probably looking to save money with a do it your self project.

    -Bill

    Bill;

    Geography lesson: Canada is not in Europe, eastern or western. :p

    (Based on his ".ca" e-mail and IP location.)
  • BB.BB. Super Moderators, Administrators Posts: 30,178 admin
    Re: Solar Panel

    Sorry to edanthony and the another Canadians,

    I got this confused with a thread by "solarpanels" who is (probably) out of eastern Europe.

    -Bill "the dumb American" B. :blush:
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Solar Panel

    S'okay, Bill; Canada was moved from Europe to North America in 1867. :p

    Er, possibly I'm confused now. ;)
  • SevenSeven Solar Expert Posts: 292 ✭✭
    Re: Solar Panel

    I think you scared him off.
  • ElectricsuperdutyElectricsuperduty Registered Users Posts: 8
    Re: Solar Panel

    what about Super Capacitors wired in series to the compressor/fan unit to help with the start up?
  • BB.BB. Super Moderators, Administrators Posts: 30,178 admin
    Re: Solar Panel

    Look very closely at the storage and performance/life characteristics of "super capacitors"... They are not usually very cost effective and cycle life can be surprisingly short in industrial usage.

    Add the fact a super capacitor needs a fairly wide range in operational voltage to store energy (E=0.5CV^2), you would normally need some sort of controller to pump energy into and remove from the capacitor--These are not just some version of a storage battery.

    -Bill

    Here is a short thread about the super/ultra capacitor math and a couple comments about lifetime.

    ultracapacitors / supercapacitors
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • edanthonyedanthony Registered Users Posts: 7
    Re: Solar Panel

    thank you very much folks.:cool:
  • BB.BB. Super Moderators, Administrators Posts: 30,178 admin
    Re: Solar Panel

    Sorry,

    Marc/Cariboocoot pointed out I forgot the link in the previous post:

    ultracapacitors / supercapacitors

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