timk225
Active Member
Nah, that is not profitable for Tesla. Their greed would rather have you buy more Powerwalls and/or solar arrays. Don't forget the greed they have shown in pricing the options for the Model S, X, and 3.
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Vehicle to home power during emergency
- Thread starter SlicedBr3ad
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Nah, that is not profitable for Tesla. Their greed would rather have you buy more Powerwalls and/or solar arrays. Don't forget the greed they have shown in pricing the options for the Model S, X, and 3.
That's how the Japanese systems work - the fast charge port gives direct access to 350V-400V DC from the battery pack, and a new external/stationary inverter converts that to 240V at 60Hz for the house.
I don't think there's any reason this can't be done or would be unsafe - but those inverters aren't cheap or compact. Actually, some companies charge almost as much as a Powerwall for an inverter of similar capacity with no batteries.
How cheap and how big they are depends on power rating. We use 3 phase 400V Variable speed drives (basically a variable frequency inverter) to do speed control of AC induction motors and at 5kW they are approx shoebox sized and not heavy. Adding enclosures and safety features for domestic uses would no doubt add a bit of size and weight, but shouldn't make then overly large or heavy. I'm not sure if putting single phase out would complicate things or simplify things.
JeffK
Well-Known Member
Energy is produced on demand. There is no surplus per se, it's either used, stored, or lost. At night there's a surplus of capacity, but not necessarily energy on the grid.
As far as EV helping the grid, the easiest method this can be accomplished is to have EVs stop charging during peak usage hours.
Tesla CTO JB Straubel On Why EVs Selling Electricity To The Grid Is Not As Swell As It Sounds
It's not about the superchargers or competition with powerwall.
OK I might have used the term 'surplus' wrong. You know what I mean, let's not pick words when we both know what the subject is.
Sure it helps not to charge at peak time, but it helps even more to store energy when it's cheap and put it out when it's needed. I mean that's exactly what Tesla is selling with the Powerwall and Powerpack products. Help the grid with power fluctuations. Help the grid by storing energy when demand is low and shift it to when demand is high. EVs can do that just fine. I charge over night, during the day I supply some to the grid, leaving plenty to drive home.
I read the argument that JB mentioned about why vehicle to grid isn't a good idea and they only make some sense without looking into it more. Once you do the numbers they are invalid. He mentioned degradation cost. We are not talking about doing full cycles every day. Maybe 20% of the battery capacity would be used, not a full 100%-0% cycle. The average driver does maybe 14k miles per year. That's about 50 full cycles per year. I drive 36k miles a year. That's another 77 cycles. After 128k miles and 3.6 years I have 7% degradation living in a hot climate and using Superchargers 60% of the time (all factors that increase degradation). An average EV can do a 25% cycle every day to help the grid resulting in the same usage that I have and degradation isn't an issue at all. So right there JB's argument about degradation cost is not very strong. Powerwalls do an almost full cycle every day. That's 7 times the cycles of an average EV usage. 20% cycle of a typical Model S battery is 16 kWh. 100% cycle on a Powerwall 2 is 10 kWh.
The other issue he brought up are interconnections and permits. Yes you need a reverse feed to the grid. You need the exact same hardware and connection and permits for any powerwall installation. Tesla has no problem promoting those for the exact same use that we are talking about. So what is it? He is contradicting himself here. The difference is clear. Tesla makes money on one, not on the other.
harry
Member
I have an EV whose battery pack I can access directly. The voltage is 150VDC nominal, and the max amperage is 500. I only need a DC to AC inverter to set up an emergency house power feed. I haven't been able to find an inverter with the right specs (150VDC in, split 120VAC out). Any suggestions?
JeffK
Well-Known Member
What would be your explanation for the use of two different battery chemistries? NCA for EV and NMC for storage...
This is a year old but it does sound like Tesla has been researching vehicle to grid possibilities: Tesla executive hints vehicles will soon drive the grid
I would be interested in an officially supported V2H solution myself. I wouldn't plan on using it regularly but would be great in emergency situations. While I don't have to worry about hurricanes, we have had ice storms which have cut the power for day. With a V2H solution, I could power my boiler (and thus heat the entire house) and not have to worry about the pipes bursting.
I agree that Powerwalls can be expensive if not part of a solar system but I should be getting some Powerwalls thanks to the referral program which makes them very affordable for me. I'm going to have those installed before solar but the ability to send power from my car back to the Powerwalls (as @Ben W mentioned) would be a great solution to keep things running for days, if necessary.
Honda had a device which would allow owners to tap into their car's battery for V2H: Honda Power 9000 Lets EV Owners Power Homes During Grid Outages
I would be interested in an officially supported V2H solution myself. I wouldn't plan on using it regularly but would be great in emergency situations. While I don't have to worry about hurricanes, we have had ice storms which have cut the power for day. With a V2H solution, I could power my boiler (and thus heat the entire house) and not have to worry about the pipes bursting.
I agree that Powerwalls can be expensive if not part of a solar system but I should be getting some Powerwalls thanks to the referral program which makes them very affordable for me. I'm going to have those installed before solar but the ability to send power from my car back to the Powerwalls (as @Ben W mentioned) would be a great solution to keep things running for days, if necessary.
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That's about what I was expecting. The 9 kVA box weighs well over 100 pounds, and according to this article the "reference" cost is 1.18 million yen - at current exchange rates just short of eleven thousand dollars, and something like 15% of the cost of the Fuel Cell car that they intended to sell it with.
For very slightly more money, you can buy two powerwalls, with more inverter capacity and 27 kWh of batteries.
Wow.
I never bothered converting the currency to confirm price. Maybe if it was $500 to $1000 then I'd be interested. $11,000? No thanks! I'll stick with the (free) Powerwalls.
I seem to remember an article where BEV owners plugged in had their cars function as peak/low buffers for the grid, making money for them.
Which brands do and will offer use of the battery as source for non-car needs at high voltage? If the warranty for the battery is in GWh put through rather than years or ODO, this should not be an issue. And a heck of a service to those spending 5 figures on a battery.
Which brands do and will offer use of the battery as source for non-car needs at high voltage? If the warranty for the battery is in GWh put through rather than years or ODO, this should not be an issue. And a heck of a service to those spending 5 figures on a battery.
Lots of discussion about it as a possibility. A few prototypes and demonstration projects by universities and manufacturers.
To the best of my knowledge, no one is offering such a system today, and no one has committed to a plan to offer it at a specific time in the future.
It may ne the oil cabal all over again, now with the utility companies. Many places do not allow you to detach from the grid even if you're well set with green energy you generate yourself. You are to take a utilities contract, or you are obviously a terrorist with no right to be in the country except jail.
Now that you mention it, you might be able to get a used Leaf for less than the cost of a Powerwall!
Given how Musk usually approaches things, I'd think he'd take that as an opportunity.
One more thing to add to the list of capabilities of Powerwall, so if you want any one of them, you get all of them. Aka, you could have:* Grid-tied solar inverter
* Battery backup for day/night power shifting
* Full home battery backup with grid disconnect
* All-in-one system for off-grid users
* Tesla-to-grid inverter for making money via V2G
* Tesla-to-home inverter for backing up your house
One of the advantages of using electronic switching with IGBTs is the ability to do whatever sort of waveform sculpting that you need to for a given situation. So it's not like every new capability that you want to add requires the addition of a whole new piece of hardware.
ED: You know, something just occurred to me: V2G could be seriously abused in places where there are free charging stations. For example, a person with free charging at work selling their power every night and filling all the way back up during the day. Or driving around to some free charging station around the corner and back repeatedly all day. You could probably make a fair salary with the latter.
Obviously free Supercharging could be abused in that case. But those issues can easily be solved. If you use EV2Grid, you have to pay for Superchargers withing say 100 miles of your home where you connect to the grid. Outside of the 100 miles you can use the Superchargers free as usual.
Using the Leaf for power in a Blackout: MY "Leaf to Home" - My Nissan Leaf Forum
Too bad the pictures are gone, it was a beautiful installation.
Don't forget to open the main breaker to disconnect yourself from the grid so that you don't endanger utility workers.
Too bad the pictures are gone, it was a beautiful installation.
Don't forget to open the main breaker to disconnect yourself from the grid so that you don't endanger utility workers.
Closer to home than you'd think.
https://www.quora.com/In-what-places-is-it-prohibited-or-punished-to-be-off-the-grid
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