If an EV has an output power of say 80kW to drive the motors when driving, why is the backup power (to power your house in a power outage) only about 10kW? It's the same battery!
And why do people say it costs thousands of dollars to fit something to do this? Surely a 10kW invertor doesn't cost much, just something to make 400VDC into 240VAC. I'd say more like 500 dollars.
Rewrite all that considering I know the difference between power and energy, I have a f****ng physics degree. When I said 80kW I meant 80kW, not 80kWh. Do you seriously think a car motor only draws 10kW?
And that last link doesn't tell you how to do it, just sales waffle about Ford are getting to it.
Pretty easy really, you find the 400V battery wire and connect a convertor to it to make 240VAC.
Then you should have figured out the answer to your question from the article. It says a bi-directional charger is required. So the inverter circuitry is in a special charger. What are home chargers built for? The ones I've seen are 240V, 50A tops. That's 12KW. So the charger and cables to the car are to support that, not 80KW. Given that even whole house standby generators are in the 10KW - 15KW range, and portable generators that people use are typically 3KW to 7KW doing 10KW from a car sounds very good. Could they redesign, at increased cost for higher power? I don't see why not, but then you're just going to drain whatever power you happen to have in the battery at the time you need it faster. There is no guarantee that it will be fully charged. And unlike a generator, what you have available in a car is very limited, so reasonable people are going to be OK with a 10KW max because they are going to use it for necessities, use it sparingly and not want to blow through it at high power usage.
One requirement is a power transfer switch. A 100 amp 240 volt single phase version on Amazon is just under $200. A 200 amp version is just under $600. Add in a few dollars for the fittings, wire etc. There was a rule of thumb years ago that parts and labor would be about the same amount. You'd hit a thousand dollars without much trouble. I'd bet labor would be higher because one would probably have to take things apart before installing the new. I don't know the additional requirements the National Electrical Code (U.S.) would impose for standby power.
I addressed reasons why 10KW is a reasonable number in my other post, but you got me thinking of another factor. The wiring in a home for EV charging is almost always going to be 50A tops, at least as of today. That's 12KW. So if you were to go higher than that your going to need new wiring from the garage or wherever, back to the panel. So add that to the list of why 10KW is reasonable and would cover the vast majority of what people actually would do with it.
Cables don't cost much, especially if they're short.
It's a pest, you have to switch stuff off.
Not if it's bursts, like cooking a meal or having a hot shower.
They usually are. If it was plugged in when the powercut started, it would have just been charging.
A Nissan Leaf would power the average house for 3 days. And decent electric cars have a battery 3 times bigger.
That's only for convenience.
$13.
Then fit it yourself.
Rules are for the obedience of fools.
If you have 24kW in the house, you might aswell fit a charger as such.
Park the car nearer the house.
This is a newsgroup, so I'm talking to whoever reads the post.
You need to shop around. I can get one for half the price that does 8kW. Anyway they have electronics to communicate with the car.
A grand actually.
Why would you do that knowing you can only get 10kW at a time? You'd spread the usage out.
No it's a safety issue to prevent backfeed from the house into the grid.
How short is the cable to go from the inverter in the garage back to the panel, which could be at the other end of the house going to be? That's where my panel is, at the farthest end of a big house from the garage.
More like just not turn things like a dryer or stove on.
Microwave takes 1200 watts. Here in the US the vast majority of homes have tank type water heaters, most of those are gas, so taking one or two quick showers, if you really need to, isn't a problem. This is for the rare case of a power emergency, not so you can live like the grid isn't down. You do have a point if you have an on-demand water heater, but given the whole car supply thing is only worth a day or two, I don't see it mattering all that much.
Obviously that's BS, especially since it takes 9 hours to fully charge and that's with a level 2, 240V charger installed in the garage. The car could be in any state of charge or not even there when the power goes out. Not being able to use the car while it's being used for power for the house is another obvious big disadvantage.
If it was plugged in when the powercut started, it would have just been charging.
Not at 80KW and living like you are still on the grid, which is what you want.
Wrong again. In the US it's a code requirement. I can't imagine it's not the same in any civilized country, for very obvious reasons.
Now you're off on to something else, the capacity of home chargers. From what I see level two chargers top out at about half that, so take it up with the EV car companies and charger manufacturer's without regard to using the car to power the house in an emergency.
I was talking about the car being in the garage. That's where the vast majority of chargers are going to be located. You still need wiring from there back to the panel to support the max amperage. Thinking this through, it seems likely that you will need a separate, additional run from the inverter back to the panel to do the standby power anyway, so add that to the costs and obstacles. Or I can buy a generator that will run indefinitely on gasoline or natural gas for under $1000 and that doesn't require the car to remain in the garage for the duration.
Summarizing:
A "Level I" charger (AKA a "convenience charger") almost always comes with the car and is designed to plug into a standard household 120VAC outlet.
Hence... it's limited to (nominally some are a bit higher) twelve amps/1,400 watts. About as much power as a toaster oven.
These will typically give your car 5 miles of range for every hour of charging.
A "Level II", which uses 240VAC, typically both has the higher (doubled) voltage and also... twice the amperage.
So instead of 1,400 watts they'll be more like 6,000 watts, and give you 25 miles/hour of charge.
These use a basic 240V outlet (the type you'd have for an electric dryer or electric stove, or a large window air conditioner..). Pretty much any modern US home has the capacity, but you might have to run cabling from your breaker panel. (Straightforward for any licensed and experienced electrician or well, err, grounded, handy person).
You can get Level II's that go a fair amount higher, but that gets tricky... And then there are the various versions of "super chargers". Your head will hurt.
Do you like being ripped off? $1K
Finally, you understood and answered my question. The difference between 10kW backup mode and 80kW driving mode is sustainability.
You're the one getting mixed up with kW and kWh.
Arrested for using your car battery for something else, yeah right.
And you too, or you would have written them down.
And in sensible countries with a proper voltage, the slowest charger plugs into a proper 13A 240V socket and gives out 3kW.
So use it next week then.
You have dryers that use 6kW?! I know American clothes are much larger, but still....
Just go for it and have a 24kW charger.
A post can be read and responded to by anyone. When I said "And why do people say it costs tho.....", you didn't seem to know who I was talking to, I can't tell to help you out now, since you snipped the attributions.
But you weren't talking about invertors, you said EVSE.
Because I live cheaply on Chinese stuff. 99p for an 18650 battery charger!
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.