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Use Of Tesla Vehicle Battery for Home Charging In Case of Power Failure

Use Of Tesla Vehicle Battery for Home Charging In Case of Power Failure

The case for seems fairly straightforward. What am I missing?

Use Of Tesla Vehicle Battery for Home Charging In Case of Power Failure

Quite simply enabling Tesla vehicle batteries for home charging in case of power failure would increase the value of Tesla cars and help improve public safety while potentially providing a source of additional revenues for Tesla

Arguments For:
- Public Safety: Provides an effective source for home heating / cooling in the case of power outages
- Value Add For Tesla Owner: Reduces need to purchase other home battery systems in case of power failure
- Advantages over PowerWall: Enables customer to refill at another location in case of power failure, doesn't take up additional space in home, much larger capacity

Arguments Against --> Remedies / Counterpoint
- Customer Overuse / Abuse: Customers would have an incentive to use free Superchargers to refill cars for use at home --> Set limits to the number of times a customer could refill and use for home use in a year
- Accelerates depletion of battery through greater non driving use --> Set limits / additional fees based on the number of times a customer could use for home use in a year
- Disadvantaged vs. PowerWall: PowerWall provides a constant source at home vs. the vehicle which may need to be used to commute --> Many customers have more than one car so could use the other car in times of power failure or call an uber, let the customer therefore make the decision if they want use a PowerWall or their car battery

Should_I | 15 luglio 2018

And then when you want to go somewhere your battery is depleted. Then we just need to put a solar panel on the roof of the car to recharge it right?
Or maybe we could run a generator off the battery to power the home and recharge the car?

SamO | 15 luglio 2018

You need a Powerwall as a buffer. Great idea

Vorg | 15 luglio 2018

@Should_I: Simple solution: There would be a setting to prevent the car battery from going below a certain level so it won't get depleted. Any other thoughts?

reed_lewis | 16 luglio 2018

Your car is for driving. A powerwall is for powering the home.

The idea of powering your home with your car is as good an idea of cooking your dinner on the engine of your ICE car. It makes no sense, and has too many negatives. Why not just attach a large alternator to an ICE car to generate power for your house. It makes about as much sense.

Vorg | 16 luglio 2018

@reed_lewis. I don't think an ICE can generate the necessary level of power and is not able to handle the flux in demand well. Can you please please list the many negatives you suggest if so many exist? Thanks.

Vorg | 16 luglio 2018

@reed_lewis. I don't think an ICE can generate the necessary level of power and is not able to handle the flux in demand well. Can you please please list the many negatives you suggest if so many exist? Thanks.

SUN 2 DRV | 17 luglio 2018

@Vorg

This is frequently discussed and Reed is right. There is a lot of complexity and cost required to make this happen, and a powerwall is just a better and more reliable solution.

You need to add (and pay for) additional hardware in the car to manage and safely Export power, you need a transfer/automatic disconnect switch for your house to remove it from the grid both for the safety of electrical workers and since your car can't power the entire neighborhood or city. You need to add and pay for a high power DC to AC inverter similar to the cost of a solar inverter.

Guess what, you've recreated most of the technologies in a PowerWall, except for the batteries themselves. And a battery system on wheels with leather seats and a nice audio system is not the most cost effective back up battery. Do you really want to leave your family in the cold and dark because your car is away from home?

A PowerWall is purpose built for backup, and is a much better and more cost effective solution, especially since you have to recreate most of it anyway.

Vorg | 17 luglio 2018

@SUN 2 DRV Thanks for thoughts. Understood on additional costs for the switch for house and inverter (not much different than a solar system as you mention). I know that I am still interested in the option since I would get 6x the capacity of a powerwall for a similar price. Seems the key question is how much would it be to add the option to the car. Any idea of the cost for additional hardware required in the car?

Yodrak. | 18 luglio 2018

Using the Leaf for power in a Blackout: MY "Leaf to Home"
http://www.mynissanleaf.com/viewtopic.php?f=37&t=13097&hilit=inverter

reed_lewis | 18 luglio 2018

@Yodrak - That is taking the 12V battery and producing 120V power. Nothing new there.

Negatives:
- You are not home and the power goes out. You arrive home with an empty battery from driving. What do you do?

- What if you are powering your home with your car, and then need to drive somewhere because of evacuation. But your car's battery is now empty. Tough luck.

I submit that having a home battery system is a much better solution to the issue of powering your home. Plus the powerwall is more meant to buffer solar power anyways, which you will do every day. Having it be a backup system is not its primary design. If you need backup power, install a generator. That can be installed and run when needed at a lower cost than using a car's battery.

Yodrak. | 18 luglio 2018

"That is taking the 12V battery and producing 120V power. Nothing new there."
Agreed.

"You are not home and the power goes out. You arrive home with an empty battery from driving. What do you do?"
The same thing you would have done before you had an EV.

"What if you are powering your home with your car, and then need to drive somewhere because of evacuation. But your car's battery is now empty. Tough luck."
Yes. That's why I'm not a fan for vehicle-to-grid proposals - great for the utility, maybe, but not for the vehicle owner.

"I submit that having a home battery system is a much better solution to the issue of powering your home."
I agree. My point is that the people who say it can't be done are wrong. It can be done. How good an idea it is is another matter,

reed_lewis | 18 luglio 2018

I concur. The whole thing is what I call "A Solution in search of a problem".

There is no advantage to it that I can think of except in some small cases. But those edge cases do not justify creating the solution when there is a perfectly good solution staring people in the face. The Powerwall is perfect for home use. Plus it is not an automatic solution. You have to plug things in and do other stuff to make it work. With the Powerwall, it just works.

Furthermore, why would Tesla do something that results in less sales of the powerwall? It is not to their advantage to do that.

Vorg | 18 luglio 2018

Good discussion, let me try to tackle issues mentioned. Btw issues were already considered earlier in the thread.
Other issues to consider?

@reed_lewis. "No advantage"
-->Please see above for advantages; Enables customer to refill at another location in case of extended power failure when PowerWall would run out, doesn't take up additional space in home, much larger capacity than single PowerWall

@Yodrak @reed_lewis. "What if you are powering your home with your car, and then need to drive somewhere because of evacuation. But your car's battery is now empty. Tough luck."
-->Solution: Could have setting on the car to stop powering the home if battery drops below a certain level.

jamespompi | 18 luglio 2018

I dont think installing a PW if you dont have solar and just want it for emergencies is practical.. $5500 would buy you a pretty nice whole home generator.

If you had the availability to backfeed your car into the home to keep the fridge on and the fans blowing (maybe even run AC) it adds a lot more value to the vehicle for people in hurricane territory.. I wouldnt worry about using all my miles up running the house because by the time id use that option evacuation wouldnt be necessary.

jamespompi | 18 luglio 2018

Sorry, $6600 per PW that only gives you 14KW each. Wouldn't last you very long if you didn't have panels

Vorg | 19 luglio 2018

@jamespompi - Agree with your point, this is the primary use case I am considering (e.g. no solar panels). Thanks.