TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker and becoming a Supporting Member. For more info: Support TMC

Can I use Model X battery to power my tools?

Discussion in 'Technical' started by tdave22, Sep 18, 2019.

  1. tdave22

    tdave22 New Member

    Joined:
    Sep 18, 2019
    Messages:
    1
    Location:
    95134
    Hi All,

    I've been working on building a small cabin on a piece of land I own and have been thinking about purchasing a Model X. The land is about 10 miles away from my house. and I usually lug a generator back and forth to power my tools, but it occurred to me: Couldn't I just use the Tesla battery pack and an inverter for power and leave the generator at home?

    I'm not sure if the Tesla Battery pack is accessible (battery terminals or something), to be able to hook up an inverter and then would the Tesla freak out - I've heard they're smart ;) - if the battery pack is being drained without the car being on? What could I reasonably power with the car if I was able to hook up an inverter? I figure I could power a drill no-problem, but what about something like a table saw?

    It would definitely save me from stupidly burning gas while my electric vehicle sits there with it's grid power untapped.

    Any thoughts?
     
  2. TIppy

    TIppy Active Member

    Joined:
    Jul 8, 2016
    Messages:
    1,346
    Location:
    Tampa, FL
    #2 TIppy, Sep 18, 2019
    Last edited: Sep 18, 2019
    The main battery is approx 400 volts, so you don't want to hook up to that. You can hook a 2500 watt inverter to the 12 volt battery. The main battery pack will periodically top off the 12 volt battery through the dc to dc converter. If the table saw is normally plugged into a 120 volt 15 amp circuit, it should work with a 2500 watt inverter.

    This might void your warranty, though. It specifically prohibits using the car as a stationary power source.
     
    • Informative x 1
  3. doghousePVD

    doghousePVD My grandfather’s car

    Joined:
    Dec 3, 2018
    Messages:
    523
    Location:
    New England, USA
    Tippy is right - you can't really use the Tesla as a power source, but it would be a great idea.

    If you are just using light weight power, such as charging Li batteries for a battery drill or a LED work light, one can use an inverter plugged into the cigarette/power outlet. It certainly won't run a table saw. I assume the 12V charger is light duty, and not built for continuous high amperage loads, and the 12V battery is pretty small.

    I do use a power outlet charger a lot for running computers and charging cell phones, but that is rarely much over a 100 or so watts. I think my inverter is 1kw or less.
     
  4. arnis

    arnis Member

    Joined:
    Apr 13, 2015
    Messages:
    876
    Location:
    Estonia
    You can't use the battery but you can use energy from battery to power your tools.
    If you correctly hook up 12V inverter you can definitely get things done.
    If you want to go really hard core you can connect up to 2000W inverter to the 12V battery terminals.
    Onboard 12V supply can give up to 2500W but vehicle needs some simultaneously. Can go above 2000W for a moment.
     
    • Helpful x 1
  5. DukeofURL

    DukeofURL Member

    Joined:
    Apr 1, 2016
    Messages:
    301
    Location:
    North NJ
    As the others have said, you COULD but you probably shouldn't - unless you absolutely need to. The pickup truck slated to be announced not long from now specifically states having a power outlet to run tools off of, but unfortunately I think it'll be years before we see that in a showroom.
     
  6. Blup85

    Blup85 Member

    Joined:
    Oct 26, 2016
    Messages:
    744
    Location:
    Chico
    If I setup 2 large 110Ah 12v batteries in parrallel and plugged in
    My MS 12v battery in parallel to ease the constant load, does it seem plausible to power 1kw from the step down DC to DC converter in an "emergency", warranty be damned?
    Asking for a friend that lives in Northern CA and looking for solutions.
     
  7. TIppy

    TIppy Active Member

    Joined:
    Jul 8, 2016
    Messages:
    1,346
    Location:
    Tampa, FL
    You wouldn't need the external batteries. The car's 12 volts battery can supply 460 cold cranking amps for surges (5600 watts), and the dc-dc converter can provide 2400 watts continuously.
     
    • Informative x 2
    • Like x 1
  8. user212_nr

    user212_nr Member

    Joined:
    Aug 26, 2019
    Messages:
    946
    Location:
    US
    Why is burning gas "stupid"? ie. what is the difference in efficiency?
     
  9. SageBrush

    SageBrush 2020: Drain the Sewer

    Joined:
    May 7, 2015
    Messages:
    10,562
    Location:
    New Mexico
    I've read ~ 12% for petrol generators. I don't know why it is so poor. Maybe a hybrid would make sense
     
  10. arnis

    arnis Member

    Joined:
    Apr 13, 2015
    Messages:
    876
    Location:
    Estonia
    #10 arnis, Nov 10, 2019
    Last edited: Nov 10, 2019
    18-20% for non-walmart $199 clearance sale generators.
    They are not as efficient because they are too small for optimal results.
    Ideally each cylinder should be 500cc and there should be 3 of those. They usually don't have turbocharger, wasting energy even more.
     
  11. user212_nr

    user212_nr Member

    Joined:
    Aug 26, 2019
    Messages:
    946
    Location:
    US
    Wow that's bad (I was thinking 10% inefficient).
     
  12. TIppy

    TIppy Active Member

    Joined:
    Jul 8, 2016
    Messages:
    1,346
    Location:
    Tampa, FL
    A gallon of gas contains about 36 kwh of energy. If we're generous, the generator will extract 0.15 x 36 kwh, or 5.4 kwh. Here in Florida, I pay about $0.11 per kwh. So that's $0.59 for moving electrons compared to $2.40 a gallon for gas.
     
  13. SageBrush

    SageBrush 2020: Drain the Sewer

    Joined:
    May 7, 2015
    Messages:
    10,562
    Location:
    New Mexico
    Yamaha is known for making the highest efficiency portable generators.
    This one
    Yamaha EF2000iSv2 Generator Review - Generator Guide
    provides 4.4 kWh from 1.1 gallons of fuel, so about 11.9% efficiency
     
  14. TIppy

    TIppy Active Member

    Joined:
    Jul 8, 2016
    Messages:
    1,346
    Location:
    Tampa, FL
    #14 TIppy, Nov 11, 2019
    Last edited: Nov 11, 2019
    That includes the conversion from mechanical to electrical energy, too. To be equitable, we would have to include the losses in charging the battery and operating the inverter. If the generator is 85 % efficient in converting mechanical energy, the extraction of useful energy from the fuel is about 11.9 / 0.85, or 14%.

    Charging the battery is about 96% efficient and running the inverter is around 90%, so about 85% overall.
     
  15. ambudriver03

    ambudriver03 Member

    Joined:
    Oct 26, 2019
    Messages:
    181
    Location:
    Downey or Scottsdale
    Did your friend do this?

    I have a 2000w inverter that I can hook up to the twin SLA batteries in my truck

    Has 140 amp alternator plus the two batteries. Should be able to power it at full bore... The cables are super thick though.

    Luckily down in Los Angeles we hardly ever lose power for an extended period.
     

Share This Page

  • About Us

    Formed in 2006, Tesla Motors Club (TMC) was the first independent online Tesla community. Today it remains the largest and most dynamic community of Tesla enthusiasts. Learn more.
  • Do you value your experience at TMC? Consider becoming a Supporting Member of Tesla Motors Club. As a thank you for your contribution, you'll get nearly no ads in the Community and Groups sections. Additional perks are available depending on the level of contribution. Please visit the Account Upgrades page for more details.


    SUPPORT TMC