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Vehicle 2 Grid yet again

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The battery will almost always be used to its full cycling potential (barring the premature loss of the vehicle in an accident) - V2G or no V2G. No potential is being wasted. What strikes me as dumb is preemptively aging the battery pack, which will bare minimum require a battery replacement, and would usually cause a whole car to get thrown away years earlier than it otherwise wouldn't have been (since most people probably won't do a battery swap on an old car). What also strikes me as dumb is dedicating cycles of cells focused on energy density to a task that would be better suited to cycles of cells focused on longevity and cost.

Cell cycle lives are finite. You can't get around this. If you allocate a cycle to one thing (e.g. V2G) then you're not allocating it to something else (like driving). You make more cycles by making more cells. Do you want said more cells/cycles to be ones focused on longevity and cost, and installed where they'll do the most good, and always connected to the grid when the grid will need them? Or do you want said cells/cycles to be focused on energy density instead, and always in a car, which may or may not be connected to the grid at a location where they may or may not be needed?

A much better option is smart charging. Like V2G, but without actually outputting power. You tell the car how much of a charge you want and when you want it, and it decides - based on grid rates, reflecting grid needs - when to actually do said charging. Smart charging doesn't impose any extra cycles on your battery pack, but it keeps vehicles from charging (unless owner needs demand it) when the grid is stressed. It of course, like V2G, requires a smart grid which can transmit power needs and forecasts.
I want to agree with your post because it’s “mostly” right. However, all of this assumes that cycle losses are greater than calendar losses. That’s NOT always the case. For low mileage drivers, it’s the opposite and V2G-full would make perfect sense. For example, my 2011 Leaf with the original crappy battery has 8 of 12 bars at less than 60,000 mi. A high mileage driver in Seattle got 150,000 mi with the same amount of degradation in 4 years. So my battery could have been cycled without any additional degradation. If I could get a financial benefit from cycling, I would have. My commute was less than 10 mi RT. Given free solar during the work day (say in California where they actually curtail solar), and giving some back at night, maybe 10 KWh out of my 20 KWh), I would definitely get a financial benefit without additional loss of use. Now, I know this doesn’t necessarily work for higher mileage drivers, but it will make sense for some. V2G makes perfect sense for people buying 300 mi EVs, just because they’ve been told to worry about range anxiety, and only driving 50 mi/day. I think there are more people out there like this than you realize. I advocate and advise 100s of people about EVs and I’m constantly amazed by highly educated people who think they need 200+ mi range to drive 2 miles to the store (I’m in a small metropolitan area that’s less than 30 mi across). Again, your or my “normal” isn’t necessarily the same as others.

I will agree with your description of V2GH (half duplex). Unfortunately, utilities want to sell power, not buy it back. From a system wide perspective, V2GF does makes sense in some areas like CA with excess solar and high costs, but the utilities will fight it because it reduces their profits and ability to charge exorbitant prices during high demand hours 4-9pm). In all areas V2GH will make sense from a voltage regulation sense, but again the utilities don’t want to pay more for the reliability. Eventually, Tesla, Apple, Google, and other forward looking companies will apply to be utilities (I think Apple already did) and start applying these principles. Tesla will have a competitive edge with stationary and mobile sources of frequency regulation, load response, demand response, all tied together with AI and historical data. Perhaps not this year, but it’s coming.
 
Here in SoCal I worry about the scenario that power goes off (because of wildfire or earthquake or mudslide or whatever) and when I go to evacuate I have only enough charge for 10 miles. My car battery is for driving my car.

Smart management of charging makes some sense to me, but I would still want a way to say "charge now, I really mean it."
This is a non-event. How many people really get down to 10 mi? Even with my degraded crappy 2011 Leaf battery, I rarely get home below LBW (25% SOC). Anyone coming home with 10 mi, probably needs a larger battery. Yes, I have a friend in Seattle with the original 2011 Leaf with 90,000+ mi who does arrive home below LBW after a 40 mi commute. They definitely need a new, bigger battery but the price is atrocious, so they keep going. V2G, if/when the monopoly utilities finally allow it, will likely only occur between 40-60% SOC, spread across millions of cars. between 40-60% SOC, batteries will last 20,000, maybe even 50,000 cycles. Fast forward into the future: 1,000,000 x 80 KWh/EV x 20% x MWh/1000 KWh x GWh/1000 MWh = 16 GWh. That’s a decent number, even if only partially available. Again, this will make the most sense when cars are filled between 9am-2pm on solar, like at California technology firms, then driven less than 100mi. Not everyone will fit that profile, but if the choice of free electricity required accepting V2G, I bet that a large fraction of those millions will opt in.
 
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So, at least according to my analysis of the survey data in 2015, V2G power is pretty expensive.

I don’t doubt your math is honest, but it is unclear to me where you factored in the cost of a stationary battery and it’s maintenance/degradation. That’s where the concept of V2X and especially V2H brings parity.

For a hypothetical trade of Tesla products, on one side of the trade a model 3 long range with a 75kwh battery costs ~$9k more than a standard range with a 50kwh battery. On the other, two power walls equal ~27kwh for $14k. If we hand wave a very conservative $4-5k for equipment to make V2H functional and we pretend installation cost for both options is equivalent (which it wouldn't be), for essentially equivalent cost and total battery capacity a prospective owner could either buy a short range M3+2 powerwalls or a long range M3 with V2H.

Should that owner choose the LR with V2H the downside is that there's no permanent home storage. However, there are massive upsides, like significantly more vehicle range, shallower V2H cycles (since the battery is bigger), significantly more home backup capacity, and battery technology that is newer/better than the technology used to calculate the math above.

For an average mileage car and an average load home the additional V2H cycles on the LR battery would most likely result in pretty inconsequential additional degradation. But...even if we try to bookend with a worst case scenario, the LR battery would never degrade lower than the SR battery from the other side of the hypothetical trade.

Certainly its not for everyone (though, one might contest the overwhelming majority of people would go for the LR in the above hypothetical...), and obviously V2X is not part of Tesla's plans right now, but its a first-order example of why V2X isn't quite the debbil that some would like to make it seem...
 
This is a non-event. How many people really get down to 10 mi? Even with my degraded crappy 2011 Leaf battery, I rarely get home below LBW (25% SOC). Anyone coming home with 10 mi, probably needs a larger battery. Yes, I have a friend in Seattle with the original 2011 Leaf with 90,000+ mi who does arrive home below LBW after a 40 mi commute. They definitely need a new, bigger battery but the price is atrocious, so they keep going. V2G, if/when the monopoly utilities finally allow it, will likely only occur between 40-60% SOC, spread across millions of cars. between 40-60% SOC, batteries will last 20,000, maybe even 50,000 cycles. Fast forward into the future: 1,000,000 x 80 KWh/EV x 20% x MWh/1000 KWh x GWh/1000 MWh = 16 GWh. That’s a decent number, even if only partially available. Again, this will make the most sense when cars are filled between 9am-2pm on solar, like at California technology firms, then driven less than 100mi. Not everyone will fit that profile, but if the choice of free electricity required accepting V2G, I bet that a large fraction of those millions will opt in.
I think you missed my point. I might have come home with 75% charge, but then in the blackout the charge gets depleted to power mine and others' homes...
 
I think you missed my point. I might have come home with 75% charge, but then in the blackout the charge gets depleted to power mine and others' homes...

Still a non-event. Any V2X capability will obviously have some user control. Basic V2G software can "Stop supplying power at XXX SOC", "only supply XX kWh", "only supply what I use", etc.. There are so many rudimentary solutions that it's practically not even worth bringing up.

Then, having hardware to facilitate true V2H energy exchange provides another layer of disconnect to the grid, further cementing the blackout scenario as "total non issue".

Really, there's minimal downside to V2X when used as part of a bigger picture energy solution.
 
Still a non-event. Any V2X capability will obviously have some user control. Basic V2G software can "Stop supplying power at XXX SOC", "only supply XX kWh", "only supply what I use", etc.. There are so many rudimentary solutions that it's practically not even worth bringing up.

Then, having hardware to facilitate true V2H energy exchange provides another layer of disconnect to the grid, further cementing the blackout scenario as "total non issue".

Really, there's minimal downside to V2X when used as part of a bigger picture energy solution.
Exactly. I couldn’t have said it better.

Unfortunately, Sometimes the bigger picture isn’t what we get in the short term. As an example, WA State with it’s excess hydroelectric power, should have incentivize EV purchasers over solar PV installations. Early on, a huge incentive up to $0.54/KWh, was given to PV. While I do appreciate what they were trying to do, and agree with PV, it just makes more sense to use more hydro in WA to power EVs and send less to CA (while putting the PV panels in CA where they produce more). However, in the end we need 100% EVs and renewables in both WA and CA (and the rest of the world).
 
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Possibly V2H is an easier starting point thn V2G. Tesla have everything they need in their PowerWall management system.

I live in a mostly sunny part of Australia so this may not apply to all countries or American states.

I monitored my 5kw solar system and home power usage for two years. I found the most cost-effective way I could go off-grid was install a 15kw solar system, two PowerWall 2s and have an 90kw electric Vehicle with V2H. Why so much? I do have a large house with a large 3 phase reverse cycle air-conditioner and a swimming pool. The AC and pool pump are two very large consumers in summer and winter. In spring and autumn my consumption is the lowest.

The principle of the design mix is I have enough solar during the day to power everything and charge the PowerWalls and vehicle. When, the vehicle is not at the house the PowerWalls have enough capacity to run the house for ~8 hours at full load (unlikely for 8 hours straight) with no solar contribution. When the vehicle returns to the house it can take over, if necessary.

When I look at my energy usage, during summer I have more than enough energy to power my house, charge the PowerWalls and vehicle. The system is basically over engineered to handle winter when solar is not as efficient and I have 4 straight days of cloudy or rainy weather. We don’t have snow. I have the added benefit that if there are 6 straight days of cloudy or rainy weather, I can take the vehicle to EV changing station and return home with another 90kw. Even in winter the solar system, PowerWall and EV will have enough to handle most days and still keep the vehicle charged enough for daily use.

I work in the city so to make this as beneficial as possible my wife, who works from home, should have the EV. She does a number of short trips a day, school runs, shopping, etc, but the vehicle would be at home for enough daylight hours.

The key point here is everyone is different and for some a V2H model would work and for others not so much.

Even if your house is empty during the day and you drive to work there is still a configuration that works. You would not need as much solar because your vehicle is not a home at the right time for charging. You would only need one PowerWall to collect the excess solar and run you house in “stand-by” mode when there is not enough sun. The vehicle does not add as much value in this case, but it could be used to avoid peak electricity tariff periods when you are at home and likely to be using more power. Then charge during off-peak.

To make this optimal Tesla would need to implement some form of complicated configuration or machine learning to maximise the balanced of Solar, PowerWalls and the EV. Rules like during a sunny day charge the PowerWall first to 80% then the Car to 100%, that way if we drive to the shops during the day there is still room to collect the solar power in the PowerWall. The profile could be different for weekends and weekdays. It could take into consideration todays and tomorrows weather forecast. So it could be very intelligent (or complicated).

Regarding vehicles battery longevity we need to move away from the traditional vehicle warranty of miles or km travelled. I guess Tesla is using this warranty model because vehicle owners can relate to it and they are trying to entice ICE customer to EV. In the future a kwhs cycled through the battery would be better measure than distance travelled. The more electrical power consumed the greater distance travelled. Unless you spend all your times at the drags doing ¼ mile runs, in which case the distance travelled is even a worst measure of the stress that has been placed on vehicle components.
 
Given the energy prices in Australia, I bet half the country would be interested in this setup. Hopefully the govt realizes grid defection is around the corner and takes action.

I expect a 180 degree reversal from Elon on V2G/H once the "million mile" battery pack is announced. It makes way too much sense having a 60-100kWh bucket of energy you can move around. Giving everyone the ability to transport this amount of energy would greatly speed the transition to cheap renewables, therefore Elon will do it.
 
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Unfortunately, the problem to be managed is on the supply side in most places, and that’s pretty independent of what the users are doing. Specifically, V2X can easily make the peak problem way worse if everyone is now charging their car during the day and not using any grid power overnight.

I think the most viable V2 solution is one that is smart enough to merge consumption and transportation of energy, and bill accordingly. In short, users should be financially incentivized to avoid peak hours on the grid.

Grid defection is the wrong approach. The problem is not the grid, it is those who control the grid.
 
Following my own local govt/market I can tell you there will almost certainly be massive incentive to charge at the "right time" in Philadelphia. We're increasingly taking control of our own supply and will jump all over the idea of smart charging under-served communities with free electricity at times of oversupply.

Free charging overnight is an efficient poverty fighter and can be easily corrupted on the hardware side for kickbacks to city council. Everyone wins! Also great for peak shaving so everyone else doesn't have to foot the bill.
 
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Unfortunately, the problem to be managed is on the supply side in most places, and that’s pretty independent of what the users are doing. Specifically, V2X can easily make the peak problem way worse if everyone is now charging their car during the day and not using any grid power overnight.

I think the most viable V2 solution is one that is smart enough to merge consumption and transportation of energy, and bill accordingly. In short, users should be financially incentivized to avoid peak hours on the grid.

Grid defection is the wrong approach. The problem is not the grid, it is those who control the grid.

I agree, V2G (using a utility managed control system) is the best long term solution, but right now V2H is the easiest. You don't' need to get any utilities or regulators involved as it's an extension of the current in home solar/battery regulations which most countries already have.

If a house has solar and the V2H system is configured to only charge the vehicle using excess solar, V2H will actually stabilize the network by remove a large source of energy that contributes to the duck effect. See The duck effect for details on the duck effect.

Managed V2G system will require the utilities, charging networks and EV vehicle manufactures to all agree on a communication standard. As well as complicated tariffs that incentivise the EV owner to allow the utility to draw energy from his vehicle.
It will be good if/when it happens.
 
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If a house has solar and the V2H system is configured to only charge the vehicle using excess solar, V2H will actually stabilize the network by remove a large source of energy that contributes to the duck effect

I think we're probably saying the same thing, just from different perspectives. I agree from the boots on the ground case study of home solar, where the owner is time-shifting their own energy, using a car's battery is a viable solution. Its a little impractical since many people work during the day and many of those people drive to work, but at least there's not a lot of issues to clear other than the basic technology.

Slightly bigger case study, in a region where solar is a major contributor to the grid and there's the ability to dynamically harness excess production using vehicles, that's also a great solution that, while a little more complicated than personal residential solar, does have the potential to have greater impact.

The issue right now is that in most places, and at least for a decade or more, solar isn't going to be a big enough piece of the production pie to make the 'bring energy home at night' concept work out for most people. In fact, a plausible near-term use of a car's battery to time shift energy production vs consumption could actually be the reverse, where a user charges up overnight at home, then distributes that energy to the grid during the day, during peak hours.

Obviously, a main reason Elon is avoiding V2X in the short term is that people would just supercharge for free and then use that energy at home at night. That's certainly not a good reason to shut down V2X for good, but until the majority of the use cases actually justify the capability, we're not going to see V2X in a Tesla.
 
The issue right now is that in most places, and at least for a decade or more, solar isn't going to be a big enough piece of the production pie to make the 'bring energy home at night' concept work out for most people.
Electric prices are already cheapest at mid-day in some places with good sun, like Hawaii and San Diego. The economics of utility-scale solar should drive this across the southwest US and parts of the southeast in much less than a decade. The problem is a lack of EVs. We need 10s of millions of EVs 'bringing solar home at night' just in these regions vs. the <1 million we actually have. Adding a few 100k to the fleet every year doesn't move the needle.

Obviously, a main reason Elon is avoiding V2X in the short term is that people would just supercharge for free and then use that energy at home at night.
That plus inadequate cycle life, the reason Tesla gives when asked (not in those exact words, of course).
 
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Electric prices are already cheapest at mid-day in some places with good sun, like Hawaii and San Diego. The economics of utility-scale solar should drive this across the southwest US and parts of the southeast in much less than a decade. The problem is a lack of EVs. We need 10s of millions of EVs 'bringing solar home at night' just in these regions vs. the <1 million we actually have. Adding a few 100k to the fleet every year doesn't move the needle....
I just did a rough calculation from yesterday’s CAISO solar chart. About 55 GWh of solar available between 8am-6pm, so roughly 1M EVs if charging 55 KWh/EV. Not a perfect estimate, but it’s better than most WAGs. This is just CAISO which I guess doesn’t include San Diego. There will be more available from now until May, less during summer due to increased AC demand, and way less in winter. My point is that we probably need solar and EVs to increase concurrently. 10x (or more implied by your comments) more EVs at this point would be much more than the current “excess” solar. Again, a rough guess, might be that we would need to add 10 GW solar capacity for every 1 M EVs:

1,000,000 EV x 50 KWh/EV x GWh/1,000,000 KWh x GW/5 GWh = 10 GW/1M EVs

U.S. Solar Market Insight | SEIA

There’s only ~72 GW solar nationally, most of which is used daily and not curtailed excess, so roughly a maximum of only 7.2 M EVs would be needed today, “10s of millions”. So, let’s just have both industries add at a ratio of about 10 GW per million EVs. That seems to be close to the annual production. Yes, it would be better to eliminate all ICE and fossil fuel electricity tomorrow, but it’s not happening for several years, maybe even decades without a rapid ramp of both.
 
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Reasons why Elon will introduce V2G at battery day:
  1. Inline with mission
  2. Million mile battery makes it sensible to do so. The car will be old before the battery.
  3. Powerwalls can't be scaled so quickly - requires electricians
  4. Adds value to the cars = profit
  5. Another moat - who will buy anything other than a Tesla car?
  6. Great marketing
  7. Provides another purpose for Robotaxis making them cost effective in areas where they will be called upon less
 
Reasons why Elon will introduce V2G at battery day:
  1. Inline with mission
  2. Million mile battery makes it sensible to do so. The car will be old before the battery.
  3. Powerwalls can't be scaled so quickly - requires electricians
  4. Adds value to the cars = profit
  5. Another moat - who will buy anything other than a Tesla car?
  6. Great marketing
  7. Provides another purpose for Robotaxis making them cost effective in areas where they will be called upon less
TEG + depleted pw + solar + grid outage + recent Y/3 +gen3 Charger = magic power