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Thin Film Solar Panel (Rollable Solar Powered Battery Chargers)

Discussion in 'Gen 2 Prius Technical Discussion' started by JeffElectric, Mar 9, 2007.

  1. JeffElectric

    JeffElectric New Member

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    When visiting my local Toyota dealer in Santa Monica I noticed a wrecked Prius in the back lot. I decided to take a closer look and noticed that the battery pack was visible because the rear seat was removed. I thought to myself, I could tap into the battery pack by connecting a "Thin Film Solar Panel" (see attachment - Iowa Thin Film Technologies Website) and potentially gain an increase in overall MPG up to to 100+. I am not an Electrical Engineer, but thought this could be possible. Can those of you that are engineers provide feedback?
     

    Attached Files:

  2. ScottY

    ScottY New Member

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    According to their spec, the highest output film gives you 15.4V at 1.2Amps, P=I*V=18.48W. That's under ideal condition I assume.

    For comparison, the Prius sitting at idle, fully warmed up, engine not running, AC not running, headlights not running. Hybrid battery pack voltage ~250V (depending on SOC, state of charge), and consumes ~1Amp. Again, P = I*V ~250W.

    Not to mention you have to step up that 15.4V to higher than 250V in order to charge the hybrid battery. Whenever you do any type of conversion, there's always conversion loss involved (electronic components are never 100% efficient).

    The film will provide less than 7% of the power consumed by the Prius while sitting idle at ideal condition. Not worth the money/time IMHO.
     
  3. usbseawolf2000

    usbseawolf2000 HSD PhD

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    Scott,

    Thanks for the info. Since you have the CAN VIEW, maybe you know the answer to this question. Does the Prius drain the HV battery (in the ideal condition you described) less in the Ign On mode (Power on without brake - amber light)?

    I always wondered how much power the inverter and others draws. 250 Watt is acceptable since all 8 ECU and the monitor (MFD) has to be on as well. A typical desktop PC draws about the same amount.

    If the headlamps are on, that's 110 Watts more. 100 Watts more if you have fog lights. Any idea how much if the radio/CD is on? I guess it would depend on the volume right? How about with AC on Auto to maintain the temp?
     
  4. ScottY

    ScottY New Member

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    <div class='quotetop'>QUOTE(usbseawolf2000 @ Mar 9 2007, 12:51 PM) [snapback]402869[/snapback]</div>
    Hey Dennis,

    In IG-ON mode, the HV battery relays are open. CAN-View only measures current in/out of the HV battery pack, so I can't tell you how much power it consumes. You will need to use an amp meter to measure if you you really need to know. The HV battery relays are closed only in READY mode. The idle condition I described above is when the car in READY mode.

    During the day time, with nothing else turn on, only fan on (no AC), the current draw is usually 1 Amp to 1.x Amp. At night when the headlights are no, I see about 2.x Amp current draw. As for the radio being on or off, I don't see any signification affect on current draw, but I have the standard radio w/o any amp installed. As for AC, that's the MPG killer. In summer time, I saw up to 10 Amp draw. Of course that also depends on the fan speed, ambient temp, and the cabin temp setting.

    Hope I answer your questions.
     
  5. usbseawolf2000

    usbseawolf2000 HSD PhD

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    Ok, I just did RTFM.

    What I asked you was not clear. Without holding the brake, if you press power button, you get to "ACC" mode (only radio works). HV battery has open relay and MFD shows no bars.

    If you press the power button again, you get to "IG-ON" mode. In this mode, the fan, wipers, power sockets, etc... works. MFD shows the HV battery with bars.

    I am asking the power consumption between when the car is Ready in Park versus the "IG-ON" mode.

    Let's say when I need to wait for someone for say 15 mins and want the fan and charge my cell phone, should I stay in Ready Park mode or in IG-ON mode?

    From a few times with my experience, I am not sure... it seems the Ready Park mode drains more power from the battery. That's why I am asking.

    The solar panel that jeffelectric mention would definately help in "ACC" mode without worrying about running down the little 12 volt lead acid battery and enjoy the music. Assuming it is day time :) of course.

    P.S: I thought HV battery voltage is 201.6 Volt.
     
  6. ScottY

    ScottY New Member

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    Dennis,

    I THOUGHT the HV battery relays are only closed when in READY mode. But I could be wrong, just like many other times.

    About HV battery voltage, the SOC will be pretty low if it reads ~200V. Most of the time (~60% SOC), I see anywhere from 21x V to 24x V depending if MG's are acting as generator or motor. If SOC is high, it reads close to 250V. I use 250V above just for ease of calculation.

    I assume that READY mode will consume more power, since all systems are on, while IG-On mode that's not the case.

    Let me go and try different things with CAN-View. Get back to you later about current draw in Ig-On mode.