Using the Clarity as an emergency power source

Discussion in 'Clarity' started by Hi.Ho.Silver, Sep 13, 2018.

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  1. Hi.Ho.Silver

    Hi.Ho.Silver Active Member

    I live in the Raleigh-Durham area and it is likely we will lose power tomorrow due to Florence. I have purchased and tested a 1000 watt 12 volt input inverter for powering our refrigerator and our freezer during the outage. I am trying to figure out a simple way to ensure that the ICE does not start unexpectedly since the car must be in the on/ready-to-drive mode to provide high power to 12V battery. I feel that it is not safe to leave the car unattended in my garage unless I can be certain the ICE will not start and generate CO.

    A look under the hood reveals a lot of electrical connectors but nothing that would obviously disable the ICE other than disconnecting the four spark plug connectors. Ideas are appreciated.
     
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  3. jorgie393

    jorgie393 Well-Known Member

    I am not going to directly answer your question, sorry. (Putting aside the wisdom of this, spark plugs seem like a good place to start. Edit: Fuse B4 under the hood is labeled as "ignition coil relay/ignition coils, via the relay" in the service manual.). But two questions:

    -I assume that this inverter clips right onto the 12V battery pos and to ground (like jumper cables)--correct? No inverter plugged into an accessory circuit could provide 1000W, as the car's internal wiring and fusing couldn't handle the 80+A involved.

    -Is this going to do what you want? Assuming the inverter actually runs at 500W (0.5 kW)average, and the Clarity's battery has 8kWH available to use (before it looks scary), that's only 16 hours of power.

    -I'm not sure if you have time now, but please freeze as much water as you can in the freezer. Or buy ice if any still available in your area. Each gallon of water you freeze will later require 0.4kWH of energy to melt it (the heat of fusion for 4L of water), and during which the gallon will stay at 32 deg. Though it won't be perfect, and depends on how warm your house is, but my guess is each gallon could add 0.5-2 hours to the time before things start to liquefy (depends on lots of assumptions).

    Note that other threads have pretty much agreed that a generator is better, but a) I doubt that is an option and b) your power needs are much less than supplying a whole house.
     
  4. K8QM

    K8QM Active Member

    I also am not going to answer the question other than to say I wouldn't risk damaging my Clarity for this. I live in Raleigh and started filling and freezing every empty bottle I could get my hands on Tuesday evening and have two coolers ready to go if needed. We ALWAYS lose power in my neighborhood but rarely for more than a couple days (except Fran when it was 11). There are power company trucks assembled all over North Raleigh so hopefully outages will be minimal.

    Good luck,

    geo
     
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  5. Hi.Ho.Silver

    Hi.Ho.Silver Active Member

     
  6. jorgie393

    jorgie393 Well-Known Member

    Apologies to the OP. He (she?) was part of an earlier discussion re. many if the technical issues if this, such as the DC-DC inverter capacity. So I trust his/her decision.

    https://www.insideevsforum.com/community/index.php?threads/clarity-as-a-back-up-power-source-dc-dc-converter-size-idle-behavior.1027/

    Also, my comment re freezing thing is true, but less important than I thought. I was trying to make the point that the heat-sink capacity of ice is not trivial compared to the smount of energy in the Clarity’s battery. But this is not the right comparison. I forgot that the coefficient of performance for a refrigerator or freezer, being a heat pump, is 4-5. In other words, they can move 4-5 kWH of heat out of the freezer for each 1kWH energy that they use. So the Clarity’s battery, driving that heat pump, has a much larger total capacity to move heat than I thought.

    Still worth freezing, but wanted to correct.
     
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  8. Hi.Ho.Silver

    Hi.Ho.Silver Active Member

    We had a 24 hour power outage in NC due to the latest hurricane (Michael). I was able to successfully run my large LG 3-door fridge along with a small to medium chest freezer plus some LED lights using a 1000 watt inverter connected to the 12 volt battery terminals of my Clarity. Both units each drew about 125 watts in the running state. During the 24 hours, I believe I consumed about 40% of the big batteries capacity. I think this a viable alternative to a portable generator for limited powering of appliances and lights.
     
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  9. KentuckyKen

    KentuckyKen Well-Known Member

    Did you have to turn the car on to have the 17kW hv battery keep the 12v battery full to do this or will it do so with the car off.
    It’s a great idea for powering an energy efficient fridge for a short duration power outage.
     
  10. Hi.Ho.Silver

    Hi.Ho.Silver Active Member

    Yes, the car has to be on in the ready to drive mode to provide power to the 12v battery
     
  11. That's great that it worked out!
    What inverter did you use?


    Fwiw, some hybrids can have the 12V battery spike a little for a very short time, while the high voltage battery pack is charging the 12v battery. That can trip the input over-voltage protection on some inverters.

    Some other tips:
    A 2-gauge, or thicker, wire should be use. It has to be connected directly to the battery.
    Make sure the inverter is not in a closed space (inside the vehicle, under the hood, in the trunk, etc). The inverter needs to cool itself.
    The electric motors on things like refrigerators have a very high initail current draw. If an inverter isn't sized correctly, it will trip and turn off the inverter from too high of a load.
    To be safe, I strongly suggest a Pure Sine Wave inverter. That's especially true for items that have motors, like a refrigerator, small AC unit, etc.


    Some suggestions for inverters:

    My main suggestion is a top quality inverter, that also costs like one. :)
    https://www.amazon.com/dp/B004L08GME/
    Magnum Energy MMS1012
    Price: $761
    1000W 12V Inverter, MFG# MMS1012, pure sine wave inverter providing a cost effective solution for smaller power needs in mobile applications, 1000W continuous power, 12v, 120VAC @ 60Hz.
    Specs: http://www.magnum-dimensions.com/file/2157/download?token=s7nyXLxB

    NOTE: This inverter can be both an inverter and a battery charger. This way, someone could have a bank of batteries, and this would keep the batteries charged. Then, when main AC power is lost, it would enable the 12v to 120V inverter. Typically, that inverter output would go to a separate breaker, or a transfer switch.
    So, with a battery like the following:
    https://www.amazon.com/dp/B01KN7K48W
    Renogy Deep Cycle Pure Gel Battery 12V 200Ah
    Price: $438.92
    You a person would have 24 kWh vs the Clarity's 17 kWh.
    However, unlike the Clarity, a person could not start the engine and/or drive it to get more gas to charge the batteries. :)



    Another inverter that is popular with the hybrid crowd,
    https://www.amazon.com/dp/B000C73A3K/
    Aims 1000 Watt Pure Sine Power Inverter 12 VDC to 120 VAC USB Port ETL Listed to UL 458
    Price: $198.66
    1000 Watt continuous and 2000 Watt surge
    Pure sine wave perfect for all equipment up to 8.3 amps
    ETL Certified to UL 458 Standards
    Over load, temp, circuit protections and low battery alarm


    I hope the above helps.
     
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  13. Hi.Ho.Silver

    Hi.Ho.Silver Active Member

    The inverter that I used is a Quesvow 1000watt continuos that I bought on Amazon for $65. I started the fridge and freezer one at a time and used less than 50% of the output.
     
  14. squishycans

    squishycans New Member

    So I know this is old, but if you press the power button twice without pressing the brake pedal, the car will start charging the 12v battery. I'm not sure what the difference is between fully turning the car on with the brake pedal, but I think it's the same effect.

    BTW, does anyone know what the power capacity of the 12v charging circuit might be? I love the idea of being able to use the car as a back-up generator.
     
  15. Hi.Ho.Silver

    Hi.Ho.Silver Active Member

    I drew 1000 Watts through an inverter connected to the battery over several hours without a problem. I suspect the AC system which runs off the 12 V draws far more than that.
     
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