Advise please soler and wind turbine

trebby91trebby91 Registered Users Posts: 2
Hi,
New Here!
I live on a boat in the U.K I have an 12 volt, 850 Watt solar panel bank on board with an Outback MPPT control unit.
I intend to fit a 500 watt wind turbine (on land) for use when there is limited sun but lots of wind.
My question is if I disconnect the solar panels from the MPPT controller (if both were plugged in I think it would fry it!) can I connect the turbine to the MPPT controller, also will I need an onshore battery to connect the turbine to when it’s not connected to the boat?
Thanks, Barry.

Comments

  • BB.BB. Super Moderators, Administrators Posts: 29,988 admin
    Welcome to the forum Trebby!

    First question is about the wind turbine itself. Many (most, all?) small horizontal axis (HAWT) wind turbines are not able to limit their maximum RPM--And if you leave a HAWT up in the wind without a load (such as a battery bank or the turbine's output lead shorted), the turbine can over-speed and self destruct.

    So the first two questions--If you connect a HAWT to a standard MPPT type charge controller (if that is what you are thinking of doing)--When the battery bank is full, the Outback would "turn off" and the turbine can over-speed.

    Similar to the question if your boat is not docked--The turbine would need to be lashed (tied down to not turn), furled/feathered/brake set/etc., or attached to a shore based battery bank to ensure that it does not over-speed.

    And lastly, a battery bank connected to a wind turbine can over charge and be damaged (or even have a melt down/catch fire if severely over charged). Normally what is done with "simple" wind turbines is to have a "dump/shut" type charge controller. When the wind it blowing, and the battery is full, the dump controller turns on and "dumps" excess current to an electric heater (or other load).

    Wind turbines also have "significant" mechanical loads. The running turbine when attached to a structure can be noisy or even have enough vibration/loads to cause damage to the structure (i.e., attaching a wind turbine to a floating dock may be problematic).

    Also, I am not a big fan of small wind turbines... The need to be installed in non-turbulent air--Which usually means at least 10 meters above the ground, and ideally at least 20 meters above the ground to capture significant amount of useful wind.

    Make sure you do your research on the wind turbine(s) you are interested in. Many will give you predicted output at various wind speeds. But many do not meet those predicted numbers in real life installations.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • trebby91trebby91 Registered Users Posts: 2
    Hi, Bill.
    Thanks for the information, as I use the boat away from its moorings and there is nowhere to dump the load after disconnection from the boat what is the answer to either burning up a stand by battery or over speeding the turbine?
    Also the turbine I have looked at is AC does this need some kind of converter to DC?
    Would I need to fit a control unit on the turbine if so to what advantage?
    Regards, Barry.
  • BB.BB. Super Moderators, Administrators Posts: 29,988 admin
    trebby91 wrote: »
    Hi, Bill.
    Thanks for the information, as I use the boat away from its moorings and there is nowhere to dump the load after disconnection from the boat what is the answer to either burning up a stand by battery or over speeding the turbine?

    Hi Barry,

    It depends on the design of the turbine... A simple turbine--Generally you just short the alternator output wires together. This makes it very hard to turn the blades.

    Some turbines have a tail that can be "adjusted" to point the blades sideways to the wind.

    Or, depending on how tall the turbine is, you can tie the blades off.
    Also the turbine I have looked at is AC does this need some kind of converter to DC?

    Yes--Generally that is a set of diodes ("bridge rectifier") with heat sinks (diodes do get hot when conducting current).

    Attachment not found.
    Would I need to fit a control unit on the turbine if so to what advantage?

    There are lots of turbine designs/variations/configuration and connection options.

    Here are some links to various sources of information (we do talk about wind here some--But there are dedicated wind turbine sites that can give you a great deal more information):

    Wind Power Links
    www.otherpower.com (good forum for DIY Wind Power)
    Hugh Piggott - Scoraig Wind Electric site for tons of info (from mike90045)
    Scoraig Wind "Recipe Book" for DYI Turbines
    www.greenpowertalk.org (added from "russ"--Like here but more wind/less solar)
    Small windpower a scam ? Survey says SO
    Truth About Skystream & SWWP
    Windmax HY-2000 2kW Wind Turbine (apparently, some vendors don't sell spare parts--just new turbines. However, the owner, Edward has been very happy with its performance from 2010-2012--BB. 5/31/2012)

    In general, I think you are better off with installing more solar panels. But if you are in a very windy area/have heavy marine layer (blocks sun)--A wind turbine can supply you with more power.

    HOWEVER--Finding a good/reliable wind turbine can be difficult--Do your research on brands/models. You need a good tower well above/away from obstructions (buildings/trees/etc.)--And be prepared for lots of maintenance (trying to service a heavy turbine on a 10-20+ meter tower is no fun either).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
Sign In or Register to comment.