Off Golf Cart...

San Diego Sun
San Diego Sun Registered Users Posts: 10
Hey gang!

I need some help here. I rent a home and would like to have a portable solar power generator that will night charge an electric golf cart.

I want to know the minimum size system necessary for the charging of the golf cart batteries. The cart will be used for running around town and will only be on the clock for about an hour at most.

What are some pitfalls? What is the best way to design a system? Are there off the shelf systems and which manufacturers are the best?

I am starting from scratch with no electrical experience but know what a panel, inverter and back up battery are...


San Diego Sun

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Off Golf Cart...

    If you have utility power (near) where the golf cart is parked... The best (least efficient, most reliable) way to generate power is with Grid Tied Solar...

    Prices are as low as they have ever been... And most utilities in California offer fairly decent net metering plans.

    Although, the devil is in the details.

    Any other off-grid type solar charging station (assuming you use the cart during daylight hours) is going to cost 4x as much as a Grid Tied System (and not really save you any money, plus saddle you with a whole much more batteries to buy and maintain--unless you are looking for emergency backup solar power too--Which is still not "cheap").

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • San Diego Sun
    San Diego Sun Registered Users Posts: 10
    Re: Off Golf Cart...
    BB. wrote: »
    If you have utility power (near) where the golf cart is parked... The best (least efficient, most reliable) way to generate power is with Grid Tied Solar...

    Prices are as low as they have ever been... And most utilities in California offer fairly decent net metering plans.

    Although, the devil is in the details.

    Any other off-grid type solar charging station (assuming you use the cart during daylight hours) is going to cost 4x as much as a Grid Tied System (and not really save you any money, plus saddle you with a whole much more batteries to buy and maintain--unless you are looking for emergency backup solar power too--Which is still not "cheap").

    -Bill

    The system will have to be "off grid" as the home we occupy is a rental and I would like to take the system with me when I leave.

    You raised a valid point too; I would like to use this system in case of an emergency for our necessary needs only.

    Does this spark any ideas? How may Volts/Amps will be needed to charge the cart and if the typical panel is a 250w how many will I need?

    SDS
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Off Golf Cart...

    Lots and Many.

    I think you are saying, you want to harvest solar all day, and then dump it into the golf cart, in an hour ? or all night ?

    Still, I'd build up a "carport" cover the roof with PV's and grid tie it. unspin the meter daytimes, and let the cart charger, charge whenever.

    What's the voltage of the cart ? # of batteries in it ?
    Maybe consider a "spare" battery pack you roll out, and exchange for the one off the 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 ,

  • San Diego Sun
    San Diego Sun Registered Users Posts: 10
    Re: Off Golf Cart...

    Good thought!

    I had not consdered the battery swap option. That may prove to be the best solution as an off grid system sounds cost prohibitive at the moment.

    How many batteries can be charged at once using a solar generator?


    SDS
  • HuntingHawk
    HuntingHawk Registered Users Posts: 12
    Re: Off Golf Cart...

    It can be off grid but not charing at night as you propose.

    First is whether your cart is 36 or 48V. That will dictate the panels you want. But you can take 12VDC panels & out them in series to increase the voltage. Two panels in series would give 24v. Three would give 36v.

    Whicher way you go with the panels, you will need a controller of the same voltage as your cart. Then you can trickle charge the cart. If you only use the cart weekdays an hour or two will keep the batteries from going too low & then weekend charging bring it up to full charge.

    Just an option to look at.

    HH
  • San Diego Sun
    San Diego Sun Registered Users Posts: 10
    Re: Off Golf Cart...

    Another great idea!

    Keep em coming...

    I use a trickle charger for my motorcycle already, so I am familiar with the benefits of using one. Will the golf cart plug easily into a trickle charger? The one for my bike hooks up to each pole of the battery, so if the cart has say 6 batteries how would the trickle charge be effective for the whole battery bank?

    SDS
  • topper
    topper Solar Expert Posts: 113 ✭✭
    Re: Off Golf Cart...

    If this Golfcart is used outside and sits outside, why not install a small system on the canopy. But I do not know your voltage or capacity and so this may or may not work. My 2 cents.
    Ken
  • ggunn
    ggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Off Golf Cart...
    topper wrote: »
    If this Golfcart is used outside and sits outside, why not install a small system on the canopy. But I do not know your voltage or capacity and so this may or may not work. My 2 cents.
    Ken

    http://shop.solardirect.com/product_info.php?products_id=1067&gclid=CIrn-qCE36wCFQLc4AodIWe11g

    Not an endorsement, just an illustration that it's being done.
  • HuntingHawk
    HuntingHawk Registered Users Posts: 12
    Re: Off Golf Cart...

    Manufacturer of the golf cart makes a difference in what you can do as far as charging goes. Some have a control circuit in the cart while others have one in the factory supplied charger.

    HH
  • San Diego Sun
    San Diego Sun Registered Users Posts: 10
    Re: Off Golf Cart...
    ggunn wrote: »
    http://shop.solardirect.com/product_info.php?products_id=1067&gclid=CIrn-qCE36wCFQLc4AodIWe11g

    Not an endorsement, just an illustration that it's being done.

    I saw that one earlier and it's pretty cool, but what if the cart has no roof like this one:
    http://sandiego.craigslist.org/esd/rvs/2727685522.html

    SDS
  • HuntingHawk
    HuntingHawk Registered Users Posts: 12
    Re: Off Golf Cart...

    To do solar on the roof you need a fiberglass roof & use then thinfilm solar. The reason is the weight you would be adding with standard panels.

    HH
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Off Golf Cart...

    Here is another golf cart recharging thread that went into a few details...

    Solar Power for EZ GO Golf cart

    Poster did not come back, so I do not know what he did in the end.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • San Diego Sun
    San Diego Sun Registered Users Posts: 10
    Re: Off Golf Cart...
    BB. wrote: »
    Here is another golf cart recharging thread that went into a few details...

    Solar Power for EZ GO Golf cart

    Poster did not come back, so I do not know what he did in the end.

    -Bill

    Thanks, I read that one before posting this thread.

    Getting back to the "how do I" question, I could use some advice. What I have heard are all great ideas, but I need to include those ideas for a roof-less cart as well as one with a roof.

    I also need to consider "off grid" as the dwelling I inhabit is a rental, so any fixed carports or alterations to the landscape would be met with stark opposition.

    I like the battery swap idea earlier from this post and am not ruling out the independant PV system or CIGS whereby I can charge the cart when not in use or in the non daylight hours.

    I am still open to all new ideas.

    Also, the family is looking to buy the new Nissa Leaf. Would this charging set up charge the "Leaf" too?


    SDS
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Off Golf Cart...

    Very roughly, an off grid solar PV system (all the parts inculding batteries) would cost you around $1-$2 per kWH (or about 10x the cost of grid power) using good quality, new equipment and batteries...

    So, as always, what is your estimated power needs per day/per season?

    If you currently charge with a 120 VAC outlet, you can get a Kill-a-Watt meter or equivalent, and measure your current charging needs (in kWH).

    Until we/you know your needs, it is very difficult to know how to proceed.

    With solar (and generator) power, the size of the battery bank and the number of kWH/Amp*Hours per day really size the system... And solar systems are difficult to grow (or shrink) later without spending a bunch more money.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • San Diego Sun
    San Diego Sun Registered Users Posts: 10
    Re: Off Golf Cart...

    That is probably the best route to take. I will buy the cart, measure the consumption and charging requirements and scale to the energy need...

    SDS
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Off Golf Cart...

    Also, you may want to consider the "range" the cart is:

    Used for (2 miles)
    Supplied with batteries for (8 miles)

    If you don't need the full range, you are just burning power dragging extra battery weight around.
    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 ,

  • San Diego Sun
    San Diego Sun Registered Users Posts: 10
    Re: Off Golf Cart...

    What is the range of each battery?

    SDS
  • HuntingHawk
    HuntingHawk Registered Users Posts: 12
    Re: Off Golf Cart...

    That is like asking two people with the same vehicle their mpg which will be different. How heavy a foot do you have? Hills?
  • San Diego Sun
    San Diego Sun Registered Users Posts: 10
    Re: Off Golf Cart...

    I have a heavy foot and like to go fast!!! We have lots of hills around town too.

    SDS
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Off Golf Cart...

    purchasing a new set of batteries will lighten your foot !!

    My friend had an EV truck (Chevy S-10 factory EV) and going up hills with a load, he'd melted the lead battery posts a couple times. Luckly, the battery shop could re-cast a new terminal right on to it, and it'd be fine till he lead footed it again ! Limp home mode was as easy as taking out 1 battery from the pack.
    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 ,

  • Eric L
    Eric L Solar Expert Posts: 262 ✭✭
    Re: Off Golf Cart...

    Having two sets of batteries and swapping them in and out of the cart would almost certainly be the most efficient, from both an energy and cost perspective. But it could get to be a pain since they're heavy and usually down inside the cart. If you don't mind the lifting it could be good exercise...

    I'd look for the carts than run on 4 12v batteries as opposed to 6 or 8 6v batteries, to minimize the hassle.

    I'm guessing here (as others said, exact details on the batteries used would be needed), but say you'd have to charge about 300 amp hours of battery at 12 volts (but the voltage needed would really be higher; perhaps 15.5 v for equalization), so in this case you'd shoot for around 30 amps at the charging voltage. That requires a mid-sized solar system and charge controller, but on the plus side, panels are currently very cheap and you wouldn't need any more expensive equipment than these two things (and perhaps the mounting). You'd also need to have the breakers and battery connects set up to safely disconnect and swap the batteries on a regular basis.

    Edit to add: really the charging voltage will more likely be in the 48 volt range (so around 60 v for eq) since you'll likely have them all in series; not charging individually.
  • San Diego Sun
    San Diego Sun Registered Users Posts: 10
    Re: Off Golf Cart...

    Thank you for all the good advice!

    SDS