Prius Prime plug-out, backup power supply for house

Discussion in 'Prime Main Forum (2017-Current)' started by mc510, Oct 9, 2019.

  1. mc510

    mc510 New Member

    Joined:
    May 15, 2019
    9
    3
    0
    Location:
    California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    I've seen chatter here and there, mostly from several years ago, about people connecting an inverter to a Prius battery, starting up the car, and then using it as an emergency power supply for their house. I haven't seen much similar chatter recently, none particularly around drawing power from the Prime's larger battery reserves, and the one company (Converdant) that used to be cited as supplying kits seems to have gone out of business. Some talk that in Japan, Toyota sells such a product, but no recent information about it.

    Anyone know the state of this topic? If properly designed and implemented (presumably with support of Toyota), it seems like this sort of thing should work very well and would be super convenient.
     
  2. Rob43

    Rob43 Senior Member

    Joined:
    Sep 24, 2014
    967
    646
    0
    Location:
    VA, BMW Race Car, BMW R1200R, BMW 330Ci, Ford F350
    Vehicle:
    2013 Prius v wagon
    Model:
    Prime Advanced
  3. m8547

    m8547 Active Member

    Joined:
    Aug 8, 2018
    498
    290
    0
    Location:
    Colorado
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    I'm planning on wiring an inverter to the 12V system, but the DC-DC converter has a limit of about 100A, so I'll limit my usage to around 80A to be safe. That's 960W, so it should be enough to run my furnace during a power outage or power some things while camping.

    I think in Japan the DC fast charging port provides direct access to the battery. We don't get that here. Even if we did there aren't many high voltage DC to AC inverters available.
     
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    83,898
    36,721
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    dead in the water

    toyota is afraid of the american legal system as they should be
     
  5. Rob43

    Rob43 Senior Member

    Joined:
    Sep 24, 2014
    967
    646
    0
    Location:
    VA, BMW Race Car, BMW R1200R, BMW 330Ci, Ford F350
    Vehicle:
    2013 Prius v wagon
    Model:
    Prime Advanced
    I have direct experience of running a home heating furnace when the power goes out...

    Getting the igniter to light the furnace is easy peasy.

    But good luck getting your 1/3, or 1/2 HP motor with its big heavy fan assembly to spin up before your inverter goes into fault mode.
    Only the best inverters can do this, ($$$$) and I certainly would NOT want a 12v inverter, I'd want a 24v or 48v interter for this job. It can be done, but it will be expensive.


    Rob43
     
  6. Salamander_King

    Salamander_King Senior Member

    Joined:
    Nov 8, 2015
    4,696
    3,557
    0
    Location:
    New England
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    A few years back, when I still had Gen3, I thought about using PRIUS as an emergency generator for the power outage. Our house relies on electrical power for both heating and water supply. We can do heating using a portable kerosene heater and wood burning stove, but no running water meant no toilet. Deep well pump's serge was too much for any of small inverter type generator, I ended up buying a dual fuel portable 7500W generator and had an electrician install whole house plug with a manual transfer switch in the main board.

    I wanted an automatic back-up generator, but the cost was astronomical compared to what I had to pay for the portable generator with manual whole house set-up.
     
    #6 Salamander_King, Oct 9, 2019
    Last edited: Oct 9, 2019
    pghyndman likes this.
  7. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    83,898
    36,721
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    agreed, we just paid 8k for a 12kw kohler, installed :eek:
     
    pghyndman and Salamander_King like this.
  8. Trollbait

    Trollbait It's a D&D thing

    Joined:
    Feb 7, 2006
    14,297
    6,235
    0
    Location:
    eastern Pennsylvania
    Vehicle:
    Other Non-Hybrid
    In Japan, instead of a typical EVSE, you can install a car to home power station that charges, and draws power from the car during emergencies. It does this through a CHAdeMO plug, so the majority of plug ins there can work as an emergency power supply. Even the Mirai has a CHAdeMO outlet in the trunk for supplying power. It was going to be an option in US models, but I think costs was a major drawback. Last time I looked a few years ago, the converted yen prices for the power stations was $8000 and higher.

    Toyota does offer a low power inverter(?) that plugs into the J1772 of the Prime in Japan.
     
  9. Salamander_King

    Salamander_King Senior Member

    Joined:
    Nov 8, 2015
    4,696
    3,557
    0
    Location:
    New England
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    Is there any annual maintenance cost?

    Our 7.5kw portable will run everything in our house except maybe baking turkey and running clothe dryer at the same time. LOL The total cost was less than $800 including the electrician cost, and no ongoing running cost other than fuel. Of course, there are certain hands-on set-up I have to do when I use it. But that happens only once every few years. Much more cost effective solution.
     
    bisco likes this.
  10. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    83,898
    36,721
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    same as any power equipment, it's a 15 hp kohler engine, iirc. oil, filters and etc. you can diy, but like everything else, i have taken to the couch and let the pros handle it.
     
    Salamander_King likes this.
  11. mc510

    mc510 New Member

    Joined:
    May 15, 2019
    9
    3
    0
    Location:
    California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    Yes, I was looking into something like that portable generator when I came across chatter about using the Prius for backup power. If it's not possible to do that in a way that's safe (for humans and for the Prius) then I certainly won't do it. But if it is possible -- and, technically, it seems like it absolutely should be -- it seems much better than a portable gas generator: you get to draw several kwh from the Prime battery before going to gas at all, gas engine/generator automatically starts and stops as needed, Prius gas engine is quieter and cleaner than portable generator, 8 gallons of gas already loaded in Prius.
     
  12. mc510

    mc510 New Member

    Joined:
    May 15, 2019
    9
    3
    0
    Location:
    California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    So you're just going to buy a generic 12VDC-110VAC inverter, attach it to the 12V battery, and draw power from the inverter? I guess the idea is that the car will notice when the 12V battery is getting low, and then ... well, what will it do? Will it start to draw power from the big high-voltage battery first? Or go right to starting up the engine/generator? Did you come across good resources that describe how to safely do this and that discuss whether or not it poses any risk of damage to the Prius?
     
  13. mc510

    mc510 New Member

    Joined:
    May 15, 2019
    9
    3
    0
    Location:
    California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    You're probably right; there's a lot of ways that this feature could be dangerously misused ... leaving car running in the garage, attempting to feed power from Prius into a wall outlet, running high-amperage appliances on light-duty extension cords ... really too bad, though; it would be such a perfect solution for those who could use it responsibly
     
    bisco likes this.
  14. Salamander_King

    Salamander_King Senior Member

    Joined:
    Nov 8, 2015
    4,696
    3,557
    0
    Location:
    New England
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    I think @Trollbait has the right answer for the reason US PRIME does not offer this option.
    For $8000, you can have a 12kw Kohler stand-by automatic backup generator installed at your house, just like @bisco did. ;)

    For Japanese, having a stand-by generator is not easy in cramped housing. And with earthquake, tsunami, landslide and typhoon to contend year after year, there must be enough demands even at that high price tag.
     
  15. Trollbait

    Trollbait It's a D&D thing

    Joined:
    Feb 7, 2006
    14,297
    6,235
    0
    Location:
    eastern Pennsylvania
    Vehicle:
    Other Non-Hybrid
    @bwilson4web and others have installed inverters into Prii without reported issues. I don't think he has plans to do so with the Prime, but I don't see installation being radically different for it.

    The downside of installing an inverter in the car is the potential for issues in the case of warranty work.
     
  16. m8547

    m8547 Active Member

    Joined:
    Aug 8, 2018
    498
    290
    0
    Location:
    Colorado
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    It measures the 12V current, and controls the DC-DC converter so that it supplies the load and charges the 12V battery as necessary (as long as the car is in "Ready" mode). I need to figure out where the current sensor is (I think it's near the battery) and which side to connect the load to (I think the load side not the battery side), but otherwise it's the same as any other 12V load like the rear defroster, seat heater, headlights, HVAC fan, brake booster pump, etc. I plan to add a ~80A DC circuit breaker (and maybe a fuse if it's appropriate) so that I don't accidentally overload the system.
     
  17. m8547

    m8547 Active Member

    Joined:
    Aug 8, 2018
    498
    290
    0
    Location:
    Colorado
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    I say "furnace" somewhat generically. It's actually a hydronic system, so I just have to power some control electronics and a small pump. I haven't measured the power consumption yet, but I expect it's 100-200W. I have a small manual transfer switch for the system so I can safely power it from an extension cord.

    And the inverter is a 2000W pure sine inverter since I plan to use it for other things as well (running off deep cycle batteries not the car).
     
  18. Rob43

    Rob43 Senior Member

    Joined:
    Sep 24, 2014
    967
    646
    0
    Location:
    VA, BMW Race Car, BMW R1200R, BMW 330Ci, Ford F350
    Vehicle:
    2013 Prius v wagon
    Model:
    Prime Advanced

    As a friend, I'm hoping you don't do this.

    If you "experience" a problem that requires warranty work, and Toyota sees tool marks or electrical arcing; you'll be Shat out of luck.


    Rob43
     
    #18 Rob43, Oct 9, 2019
    Last edited: Oct 9, 2019
  19. mister2cool

    mister2cool Junior Member

    Joined:
    Sep 26, 2019
    73
    36
    3
    Location:
    New Jersey
    Vehicle:
    2020 Prius Prime
    Model:
    Limited
    I had a 22Kw whole house Generac installed for just under 10K, that includes automatic transfer switch and a year of maintenance, and it would power up everything except the oven. it could have done that too but I could only have 4 high amp circuits and I happen to have 4 AC zones so I decided that I could do without an oven for a little while during outage.

    After hurricane Sandy, there was massive lines at gas stations where people try to get a can of gas to run their portable generator. A car would very much be in the same boat. No gas would mean even a Prius wouldn't be able to help you out. That's when I decided not to rely on gasoline for backup power.

    it's definitely a more cost efficient way to provide backup power IMHO than rigging out a car to do so. I have had the generator ran a week straight during a really bad winter storm and it had proven to be worth every penny. maintenance is really very simple as it is no different from any other power equipment. Oil change once a year (or 150 hours of run time).. oil filter\air filter and 2 spark plugs. Generac sells a maint kit for $30, which is really just an air filter, oil filter and a pair of plastic gloves. It takes 1 qt of automotive oil. If you are not a DIYer, maintenance contract is about $300 a year.
     
  20. smyles

    smyles Member

    Joined:
    Jan 1, 2019
    260
    175
    0
    Location:
    US
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Premium
    Yeah but when zombies come, I can drive away in Prime...
     
Loading...