Wind Charge Control / Dump Load Question

System
System Posts: 2,511 admin
I want to add a 800 watt wind generator to my off grid cabin. I currently have a 90 watt solar panel and an 8 amp charge controller keeping the batteries charged between weekends.

If the wind gen works out I want to add additional generators in the future.

In my quest to find a charger that can handle the wind and solar plus provide a dump load to keep the batteries from over charging I'm not finding a controller that meets my needs.

The controllers, I have found, that would handle my 890+ watts and have a dump load feature do not provide a controlled (multi-stage) charge. They connect the solar and/or wind leads directly to the batteries and then activate the dump load when the batteries reach a set voltage.

Is there a charge controller that will provide multi-stage charging and a dump load feature in the same unit or do I have to purchase two separate units?

I'm concerned with the equalization mode (usually around 14.5 v} of a separate multi-stage charger activating the dump load (also usually around 14.5 v), of a separate controller, when the batteries are equalizing.

I'm frequently away for several weeks and need the system to maintain my batteries properly during that time.

Any suggestions on a controller that would serve my needs with room for additional wind and/or solar?

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Wind Charge Control / Dump Load Question

    I believe lots of the more complex controllers will do three stage diversion controller... This one is the Xantrex C40.

    As far as I know (which is not that far :roll:), these multi-function solar charge controllers can only do one function at a time... They are Solar Panel series charge controllers, or configured for diversion, or for load control (turn of load when battery near depleted).

    If the installation needs to meet building code/NEC, you are supposed to install two diversion controllers in parallel--in case one controller/load fails, the second can take over and prevent boiling the battery dry and causing a fire.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Wind Charge Control / Dump Load Question

    Solar and Wind cannot share a charge controller. And I'd venture to guess, if you have multiple windmills, each should have its own controller.
    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 ,

  • GreenPowerManiac
    GreenPowerManiac Solar Expert Posts: 453 ✭✭✭
    Re: Wind Charge Control / Dump Load Question

    "Solar and Wind cannot share a charge controller. And I'd venture to guess, if you have multiple windmills, each should have its own controller."

    Couldn't disagree more, Mike. You have the same charge controller as I do. Morningstar TS-60. Inside the instruction booklet has a wiring diagram for wind turbines and solar panels together under one controller.

    I've been doing this for over a year with 3 wind turbines and three Solar arrays.

    One setup has: 2 wind turbines (1200 watts max) & 29 Solar panels (2.1kw watts)

    2 turbines are hooked directly to 15 battery bank.
    Solar panels are "Shared to split the incoming load" between two MPPT controllers with diversion loads and have heat sinks built in for an extra protection of over voltage/amperage. One diversion is a D/C heater/cooler and the other is a thermostat controlled set of CPU fans to draw hot or cold air from the heater/cooler. My banks are large enough to take everything mother nature has so far.

    Could always add a battery or two for the unexpected extremes. Why not divert the extra power to where you can use it.......
    Nature's Design & Green Energy on FaceBook : Stop by and "Like" us anytime.. Many up-to-date articles about Renewables every day.
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  • System2
    System2 Posts: 6,290 admin
    Re: Wind Charge Control / Dump Load Question

    After further review I found that the PMA wind generator is rated at 800 watts @ aprox 24 mph and can go as high as 1400 watts. I found an adjustable controller that will divert up to 440 amps so I have room to add additional solar, wind and hydro to my system.

    I'm going to get a 600 watt water heater element to divert some of the load and I found some .75 ohm 300 watt resistors that I can connect together and will end up with 1500 watts of diversion load. In the winter months I can use 3x 300 watt electric heaters to help keep the cabin warm if the wind is blowing.

    Maybe some day they will come out with a multistage charger that can handle the high amperage of a wind generator.
  • GreenPowerManiac
    GreenPowerManiac Solar Expert Posts: 453 ✭✭✭
    Re: Wind Charge Control / Dump Load Question

    Pooh-Bah,

    Don't you mean 44 amps ? 440 is enough to power 2 homes. My PMAs each produce 0-600 watts. 0-40mph wind & 3amps at 12v to 10amps and 60v with 40mph wind. Using that formula you're getting about 1400 watts / 60v = 23.33 amps max. Depending on your setup, likely get another few amps from a larger system. My wingspan is about 4'. What kind of span are we talking here ?
    Nature's Design & Green Energy on FaceBook : Stop by and "Like" us anytime.. Many up-to-date articles about Renewables every day.
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  • System2
    System2 Posts: 6,290 admin
    Re: Wind Charge Control / Dump Load Question

    The charge controller I found energizes an exterior mounted contractor that can handle 440 amps.

    The PMA has 9 blades with a 5' diameter.

    Are you saying that the PMA's voltage is going up as the wind speed increases? I din't know that. I was thinking that at 1500 watts @ 12v you would have 125amps to deal with not 1500 watts @ 60v= 25 amps. This changes my thinking on this.

    I was told by the PMA manufacture the high amperage was why the PMA was connected directly to the battery instead of going through the charge control like a solar panel.
  • GreenPowerManiac
    GreenPowerManiac Solar Expert Posts: 453 ✭✭✭
    Re: Wind Charge Control / Dump Load Question

    The amps are all based on primarily two things: RPM (wind speed) and strength of the Neodymium magnets on the rotor. Mine are N42 strength. Size about 1/2" x 1/2" x 1/8" thick studded on each rotor lobe. One magnet is capable of lifting 2-3 pounds of steel each. The stronger the magnet, the higher the wattage/amps/volts produced with rpms. Each side of the rotor has 7 lobes meshed close together, but not touching. One end of the rotor lobes must be South polarity and other end North polarity to create flux on all 3 phases while spinning inside the stator coil. Really strong magnets can produce the 24v or 48v output easily at one startup rpm like 150 rpm.

    I have a PDF file download on my main page that describes my setup and has a power curve chart. For the most part, I don't allow my turbines to spin out of control if I can help it.
    Nature's Design & Green Energy on FaceBook : Stop by and "Like" us anytime.. Many up-to-date articles about Renewables every day.
    WWW.GreenAnything.Net    Ad free website.
    Lots of DIY Renewable Energy Projects on ETSY : Solar Panel builds, Wind Turbine builds, Rain Barrel build,etc.  
  • scottj
    scottj Registered Users Posts: 7
    Re: Wind Charge Control / Dump Load Question
    I want to add a 800 watt wind generator to my off grid cabin. I currently have a 90 watt solar panel and an 8 amp charge controller keeping the batteries charged between weekends.

    If the wind gen works out I want to add additional generators in the future.

    In my quest to find a charger that can handle the wind and solar plus provide a dump load to keep the batteries from over charging I'm not finding a controller that meets my needs.

    The controllers, I have found, that would handle my 890+ watts and have a dump load feature do not provide a controlled (multi-stage) charge. They connect the solar and/or wind leads directly to the batteries and then activate the dump load when the batteries reach a set voltage.

    Is there a charge controller that will provide multi-stage charging and a dump load feature in the same unit or do I have to purchase two separate units?

    I'm concerned with the equalization mode (usually around 14.5 v} of a separate multi-stage charger activating the dump load (also usually around 14.5 v), of a separate controller, when the batteries are equalizing.

    I'm frequently away for several weeks and need the system to maintain my batteries properly during that time.

    Any suggestions on a controller that would serve my needs with room for additional wind and/or solar?

    The c-40 or c-60 has to be dedicated to the dump load. Both SWWP and Power-one,(Aurora), have a control box for the dump.
    http://www.windenergy.com/products/whisper_500.htm
    http://www.power-one.com/renewable-energy/wind-inverters.php#
    This is the PVI-7200-Wind interface