Starter PV System, Off Grid, Input needed.

2k2jet2k2jet Registered Users Posts: 7
Hello,

DISCLAIMER:
This is going to be my beginner project to get my hands dirty with solar. LOL! ;)

The plan is to run an above ground pool pump/filter system for a small 14' above ground swimming pool. As for what I'm looking for is recommendations for cheap batteries, I've even been thinking of hunting down used 6v golf-kart deep cycle batteries. I currently live in a rented house which is why the system will need to be on the ground with up to about 6-8 hrs [maybe 4 hours more is I trim a tree] of direct sunlight. It's also the reason why I don't want to start off high end from the get go, when I purchase my house then I shall splurge. The pump will run between 4-6 hours per day, only a 2000gal pool and pump/filter are rated for up to 15,000gal, so a few hours should be enough to keep everything clean.

PANELS
As far as panels go, I'd really like some recommendations, I'm in North Port, FL and can make a quick run to these guys -Sun Electric- in Miami. ((Unless someone steers me clear from them))
I was thinking on going for the Evergreen Panels, I know there maybe warranty issue with the company in the future, but I doubt I'm going to need that many panels for this system.

POOL PUMP
This is the pump I intend on using. GAME SandPro 50 Pool Filter System
It states 110v/60Hz, but I can't find the Amps, argh going to have to call after memorial day.

CONVERTERS/INVERTERS/CHARGERS
Here is where I prefer not to go cheap on. I plan on building a larger scale project once I purchase my new home. These items would be ideal to have them "transferable" to a newer larger system.

BATTERIES
I'm thinking a system with 4 Panels (not sure on watt size as of yet.)
and 4 6v batteries deep cycle golf-kart batteries.

Any suggestions and/or personal experience with items is greatly appreciated.
I've been reading a bit on the forums, but I'm sure pool pumps are a bit different since they require more power to get them going, (so I've read).

I think I'm at a stand still since I don't know the amps / watts requirements for the pump/filter, but maybe someone is currently using the same one?

Thanks in advance.

(( I'll be trying to attempt a DIY step-by-step documentation on this project for personal use and for the forum. ))

Comments

  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Starter PV System, Off Grid, Input needed.

    Welcome to the forum.

    Well you picked one of the worst possible projects for solar: pumping water. :roll: Not as bad as running air conditioning or electric heat, but it's right up there on the "don't try this at home" list. :p

    Discouraged yet?

    First thing you've got to do is come up with some power consumption numbers for this pool filter. Without that you're just shooting in the dark/playing a guessing game/barking at the wrong tiger. Whatever. Got to know how much power you need before you can figure out how to supply it.

    Some of the forum members live in Florida (and other warm climates) and might know about the pool equipment you mention already. I can only guess that the 1/2 HP pump shown is a typical induction motor type, which uses megacurrent to get started and does not like inexpensive MSW type inverters.
    Depending on how hard it is worked, it could drawn 1.2 kW. Multiply by 4 hours running and see the kind of astronomical power consumption figures you get in to.

    You sure you wouldn't want to start off with something easy like running a few lights and the TV when the power goes out? ;)
  • 2k2jet2k2jet Registered Users Posts: 7
    Re: Starter PV System, Off Grid, Input needed.

    lol... Yay for me!

    As far as considering lights/smaller items/etc.. I don't want to setup anything inside the house, or interfering with the house because I don't actually own it.

    The setup will be done in a shed type enclosure.

    I'm not feeling two discouraged, let me find out how much energy is needed and then I'll have a better idea at what the big picture is. (I don't think this pump uses nearly as much power as normal pool pumps.)
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Starter PV System, Off Grid, Input needed.

    I'll give you a rough estimation of recharging those four golf cart batteries. They're usually 225 Amp hours. It's likely they'd be in a 24 Volt configuration to run that pump, so you're looking to get 22.5 Amps @ 28.8 Volts: 648 Watts. Panels have to be derated because they put on an average amount of power which is less than the rating. So you're looking at around 850 Watts of array. Four 210 Watt panels would do it. Plus you need a charge controller, and for that size array MPPT type is worth the investment.

    Speaking of investment, $5,000 would probably not be an unexpected expense here for the equipment, including inverter like this: http://www.solar-electric.com/maenms4040wa.html

    Note that I run the whole cabin on about this much power, including full time electric refrigerator, computer/satellite/phone set up, water pumps, lights, even microwave. But I sure wouldn't want to have to run a 1/2 HP water pump of any type for four hours straight. I'd expect the above system to manage it for about 3 hours.
  • 2k2jet2k2jet Registered Users Posts: 7
    Re: Starter PV System, Off Grid, Input needed.

    Found one on eBay that is actually much cheaper and it claims 20gpm at 150 watts, it's a 1/5 hp motor.
  • 2k2jet2k2jet Registered Users Posts: 7
    Re: Starter PV System, Off Grid, Input needed.

    Speaking of investment, $5,000 would probably not be an unexpected expense here for the equipment, including inverter like this: http://www.solar-electric.com/maenms4040wa.html

    I wouldn't mind spending some money on quality inverters because when I move, I;d be looking to expand the system at this time, I will run things like lights, and other things that are more reasonable.
    Note that I run the whole cabin on about this much power, including full time electric refrigerator, computer/satellite/phone set up, water pumps, lights, even microwave. But I sure wouldn't want to have to run a 1/2 HP water pump of any type for four hours straight. I'd expect the above system to manage it for about 3 hours.

    lol.. when you say it like that it really sounds illogical to even bother with the pump, I found a pump that states 150w though. Would your assumption still be similar in expense?
  • mike95490mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Starter PV System, Off Grid, Input needed.

    As a renter, it's not likely your landlord would bother with the permits, but your best "bang for the buck" would be:
    a) high efficiency pool pump
    b) ground mount solar with grid tie - skip the messy batteries.
    or
    c) "Guerrilla Solar"
    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: Starter PV System, Off Grid, Input needed.
    2k2jet wrote: »
    lol.. when you say it like that it really sounds illogical to even bother with the pump, I found a pump that states 150w though. Would your assumption still be similar in expense?

    Pumps are funny things. They don't play be the rules. 1 electrical horsepower is 746 Watts. Therefor a 1/5 HP pump should use 150 Watts. Nobody told the pump that, though. They are usually rated in mechanical HP and will draw whatever current they need to achieve speed against whatever load is put on them: more load, motor slows, current increases. You just can't depend on the HP formula.

    Also a 1/5 HP pump will not do the same amount of work in the same time as a 1/2 HP pump. It may run longer and use more power. Or not; because you don't really know the efficiency of either one. I've got a "1/3 HP" water pump that draws 800 Watts on the Kill-A-Watt meter when running.

    How's that for an uncommitted non-answer? :p

    If you already have the (a) pump you could run it through a K-A-W and get some real numbers on it. I've found the "plate ratings" on many items (not just motors/pumps) are works of fiction compared to what the device really uses. Sometimes it's better, sometimes it's worse.

    Sorry about the depressing response. You sure you don't want to run an extension cord through the window and save on the lights? :p
  • 2k2jet2k2jet Registered Users Posts: 7
    Re: Starter PV System, Off Grid, Input needed.
    Pumps are funny things. They don't play be the rules. 1 electrical horsepower is 746 Watts. Therefor a 1/5 HP pump should use 150 Watts. Nobody told the pump that, though. They are usually rated in mechanical HP and will draw whatever current they need to achieve speed against whatever load is put on them: more load, motor slows, current increases. You just can't depend on the HP formula.

    True, going to do a bit more research on the pumps I guess, its sucks that no one stocks them locally, So I can't just run down and check one that's on display. lol without biting the bullet.
    Sorry about the depressing response. You sure you don't want to run an extension cord through the window and save on the lights? :p

    No worries, I prefer the raw information, rather than beating around the bush. As for the interior lights .. I really don't have any lights that are the plug type, all the ones that I use are ceiling light/fan combos to keep the air circulating throughout the night and day, and I just keep 1 low wattage bulb, where it's supposed to take 3/4 bulbs.
  • 2k2jet2k2jet Registered Users Posts: 7
    Re: Starter PV System, Off Grid, Input needed.

    bought the pump.. will report back with some readings
  • 2k2jet2k2jet Registered Users Posts: 7
    Re: Starter PV System, Off Grid, Input needed.

    Update ::

    I monitored the current cheap pump that the pools comes with to see how much it consumed with the idea of possibly switching my plan and running this pump on solar 24/7, ( my guess 2 panels 2 batteries, small simple to get me started with the whole solar deal. )

    Results: 1.35kw in 27.5 hours for a total of 49 watts per hour. I'm guessing I need a battery bank with at-least 100 Ah to be able to run for a 24hr time period.

    Distance of panels will be between 10-20 feet ( the further I go the more amount of sun I'll get. Damn neighbors trees! )

    Does this seem more manageable as a starter system Cariboocoot?

    Also, I'll probably build a raised box which will house all the equipment and keep it from the rain.. etc
    Box would be wooden with vents on both sides, ( some small computer fans should do the trick ).
  • icarusicarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Starter PV System, Off Grid, Input needed.

    If the batteries are outside you probably don't need a power vent.

    1.3 kwh/day is going to require ~400 watts of panel. I think you are going to need more than 100 ah of battery. 1300 WH from 12 vdc is ~108 ah.

    Assuming 6 hours of sun, that leaves the battery to supply power for 18 hours. That means you need to provide ~80 ah to run the system over night. So to deliver 80 ah in 6 hours you will need ~ 13 amps of charge, just to recharge from last night. Add in the loading while the pump is running, you have to add back as much as the load is drawing. 50 watts I not 12 vdc is another ~4 amps. So the panel size should deliver ~20 amps,, or about 400 watts.

    To prolong battery life, you don't want to draw more than 50% on a regular basis, and 25% is a better target number if you wish your batteries to have a long life. So, if you only wish to draw down to 75%, you would need a battery~ 320 ah. If you wish to draw to 50% you would need ~160 ah.

    If you haven't read these, I suggest you do so:http://www.batteryfaq.org/

    http://www.windsun.com/Batteries/Battery_FAQ.htm#Lifespan%20of%20Batteries

    Good luck and keep in touch,

    Tony
  • Paul54Paul54 Registered Users Posts: 18
    Re: Starter PV System, Off Grid, Input needed.

    Do you really need to run your pump more than 1 or 2 hours per day? I'm just guessing, but 2,000 gallons of pool water ought to be able to be filtered pretty quickly. Can you limit your filtering time to daylight hours?
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