What's the proper setup?

dawson_10dawson_10 Registered Users Posts: 2

I'm making a small  12 V dc wind turbine for camping so I have a way to charge my phone and small things like that. I was wondering what exactly the best set up is for this. From looking online it looks like   wind turbine to controller to battery to inverter is the best way. 

Is this the best set up? or is their another way of setting this up.


  • PhotowhitPhotowhit Solar Expert Posts: 5,698 ✭✭✭✭✭
    Gosh I can't argue against this enough...
    Will you only be camping in the desert? How will you get your turbine above tree level? 
    If All the thing will charge of USB, like phone, tablet, some fans, lights.... I'd use a portable solar array designed just to charge a battery bank. You can find a bank that will store 20,000 mahs for pretty cheap and a 20 watt portable array for around $100 total. No extra charge controller, can pre-charge and have plently for a lot of weekend trips...

    Here's a photo of a 10,000mah power bank, my phone and a USB fan.

    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • BB.BB. Super Moderators, Administrators Posts: 32,226 admin
    It looks like you are somewhere in Ontario Canada?

    During winter, that certainly puts a "crimp" in your solar harvest. Lets say you can tilt the panel based on the seasons (less tilt in summer, more tilt in winter):

    Average Solar Insolation figures

    Measured in kWh/m2/day onto a solar panel where the angle is adjusted each month to get optimum sunlight.

    More or less, 3 hours of more of sun is a goodly amount... Less than that, and you are either looking at a way oversized array, or using some other backup power source (genset, possibly a wind turbine).

    Just for discussion, lets say that you have a 20,000 mAH (20 AH) @ 3.2 volt Li Ion USB power brick (the AH rating of these is really a "lie"--But marketing wants "bigger numbers"--Typically most are 10,000 mAH @ 6.4 volts--But that is another story). And say you need power from February through October:
    • 20 AH * 3.2 volt Li Ion batteries * 0.70 battery bank "derating" for longer life = 44.8 WH of usable capacity
    • 44.8 WH per day * 1/0.61 DC solar eff * 1/2.98 hours of sun "Feb average day" = 24.6 Watt "minimum" array
    That is not too bad--A 25 Watt panel is not that expensive or that large--Pretty easy to pack, or even mount to the roof of your vehicle. A wind turbine on a pole (ideally >30 feet off the ground) is going to be a big pain to pack around/setup/break down... And almost being useless if you have any trees/up wind obstructions around you.

    The typical wind turbine ("simple" type)--They just run a small alternator through a rectifier for DC power, then that to the battery bank. When the battery is charged, the "excess" current to sent to a resistor (load bank) to burn off excess current, or to shut down the turbine (one easy method is to "short out" the alternator and "stall" the turbine).

    Generally, it is much cheaper to conserve power, than it is to generate it. Look at your tools/loads/needs and try to minimize those loads. Carry a few extra batteries/USB bricks, and a smallish solar array--And you can run a few loads (cell phone, only on when needed, etc.).

    Have you found a small wind system that interests you? In general, most small wind do not generate much useful energy... Has to be a pretty windy site to get useful power (top of hill, edge of cliff, etc.). And "portable charging"--If hiking--Strapping a small solar panel to the back of your pack can help... But mostly, wind or solar, it is fixed during the charging time (windy, or sun is up)... Portable use while charging is not really going to harvest much energy.

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • dawson_10dawson_10 Registered Users Posts: 2
    edited May 4 #4
    Hey, so thanks for the reply. To get into things about 6 months ago I got a 3D printer so I've been getting pretty good with it and and wanted to make something that will take more skill. I found a person who has 3d printed one and posted the files for everyone else to make. I know that making a wind turbine is not the most ethical way to get power but I also don't need much power as I need to charge my phone once every 2 days while camping. This wind turbine is using a dc stepper motor so a rectifier is not needed if I'm correct. I'm also from southern Ontario so the wind is decent and if I go camping for a week I'm almost guaranteed a couple windy days.

  • BB.BB. Super Moderators, Administrators Posts: 32,226 admin
    You are very welcome Dawson...

    Also, a question... Have you looked into the DC Stepper motor and how they work/are wired?



    A true DC motor with brushes and a commutator are not stepper motors (the generators on old cars vs alternator on new cars). The brushes and commutator are, basically, a "mechanical rectifier".


    Stepper motors are typically a version of an AC synchronous motor.

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