Tuesday, October 19, 2010

Solar Power

Having selected the robot I plan to use, the next step is to find a suitable solar power solution.

What I need is basically a reasonably priced solar panel capable of charging the same power pack that I used for Project Hampture. It's just a regular car battery in a fancy enclosure with an integrated inverter so you can plug a standard 110v power plug into it.

To charge that, I need this solar panel to come with an inverter that has a standard 110v outlet integrated. Do they all? Do only some? Many "all in one" systems don't clearly show the inverter so I can't tell if they have an outlet. Many include what looks like a cigarette lighter plug and a pair of jumper cables, presumably for charging car batteries directly but of course that's not what I need.The rover battery is pretty substantial for it's size. 2 hours of runtime may not seem like much, but for a telepresence robot with always-on wifi, a webcam and powerful motors it's phenomenal. So assuming it's in nearly constant use, pausing to charge for three hours between every two hours of operation. Let's say 6 hours of charging, total, per day (as it won't get much use when it's dark out) I believe the charger supplies 9 volts. Would a 60 watt panel suffice? Or is that overkill? I can get a 15 watt panel that's the perfect size and is much cheaper, I just don't know if it'll keep up with the rover's drain on the main battery. I'm also new to solar and have no idea how to translate solar power into something with a 110v socket I can plug the battery pack into. Any advice would be appreciated.


  1. 12 hours
    9 Volts
    60 or 15 watts
    A=6.66 amps or 1.66 amps.
    You should check your battery and see how many amp-hours it stores.
    You can charge 20 amphours in 3 hours with the 60 watt one, or 5 amphours in three hours with the 15 watt one.

    of course, with losses, it will be somewhat less, so you'll have to actually test it. But that's the theory.

  2. I work with solar panels, if you have any questions after the poster above me, don't hesitate to ask:)
    I think I also advised you on this subject on a thread on /sci/?