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EVs Are Essential Grid-Scale Storage

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Re: EVs Are Essential Grid-Scale Storage

#131

Post by ceejayoz »

gwbas1c wrote: post #96
ceejayoz wrote: post #52

Earlier quoted context omitted.

Or "always leave me 150 miles of range".

At that point it's cheaper to buy a car with a smaller battery and use a stationary battery for grid storage.

I might want a car with 300 miles charge for vacations, but most of the time be making trips to the grocery store. The grid might only dip into my car's battery for a 15-30 minutes at a time to prevent brown-outs while power plants spin up.

There are plenty of scenarios where the EV makes more sense than a dedicated battery for it.

Re: EVs Are Essential Grid-Scale Storage

#132

Post by TheLoafOfBread »

schiffern wrote: post #130
TheLoafOfBread wrote: post #122

Earlier quoted context omitted.

Exactly. This is just offloading of expensive energy storage to consumers, so energy company can show bigger profits.

"Quick, don't make the world more efficient! The wrong people might also benefit..." This strikes me as the opposite of "planting trees whose shade you'll never sit under." If the latter makes civilizations great, where does the former attitude lead?

There is no reason to subsidize energy companies. They are operating renewable power plants, which have intermittency issues, they should be solving this problem. I don't see any reason why I should be part of their problem of their own making.

Re: EVs Are Essential Grid-Scale Storage

#133

Post by theluketaylor »

schiffern wrote: post #40
Yizahi wrote: post #10

Aren't people wary about using their very expensive car batteries for the grid? E.g. imagine you plug in your phone for the night, but instead of a single top up change it is now constantly discharging and charging again. Lifetime of pocket sized batteries is not too great even now, and in such scenario they will go bust 2-3 times faster, in year instead of 3 or so. Also discharge swings would be probably much bigger…

> instead of a single top up change it is now constantly discharging and charging This is where V1G beats V2G. V1G (AKA grid-adaptive charging) just chooses when to charge the car, to efficiently spread out the grid load overnight and spatially across the network. No extra charge cycles, in fact it's probably more mild than just charging at full speed. The key is that you need a UI setting for "Immediately charge to…

> The key is that you need a UI setting for "Immediately charge to X%" and "Charge to Y% by Z:00." This avoids the problem where you find yourself without enough charge to get to work (or the local hospital).

I would be happy to let the grid operator decide when to charge my EV, especially if I could inform them when I wanted charge by and have an override button to be ready for road trip departures.

I wonder how long it will be before the grid operators are subsidizing parking lot operators and businesses to install tons of smart L2 chargers so commuter vehicles are absorbing all the excess solar power available mid-day that would otherwise go to waste.

Re: EVs Are Essential Grid-Scale Storage

#134

Post by ben-schaaf »

shagie wrote: post #76
trashtester wrote: post #46

Earlier quoted context omitted.

> Buuuut... Delaying charging till later is free. This functionality is already there. > So each kwh cycled into and out of the battery costs 8 cents. This is quite much. If you add other infra overhead, feeding power back into the grid is not going to produce much revenue for the individual unless the selling price is maybe 20 cents above the price when charging. On the other hand, something that MAY make more sense…

> And even for grids where blackouts are infrequent, if your car can serve as large UPS for your house (combined with a large capacitor to keep the power stable), such functionality in the charger may be worth the cost of the hardware for many people. (Bringing the number of units up and hence the cost per unit down over time.) https://www.tesla.com/sites/default/files/downloads/tesla-ne... > Warranty Limitations > T…

> All model year 2013 and newer Nissan Leafs are approved for use with the FE-15 bidirectional charger, and the automaker states that battery warranties will not be affected.

https://www.theverge.com/2022/9/12/23349971/nissan-leaf-bidi...

Re: EVs Are Essential Grid-Scale Storage

#135

Post by bryanlarsen »

TheLoafOfBread wrote: post #132
schiffern wrote: post #130

Earlier quoted context omitted.

"Quick, don't make the world more efficient! The wrong people might also benefit..." This strikes me as the opposite of "planting trees whose shade you'll never sit under." If the latter makes civilizations great, where does the former attitude lead?

There is no reason to subsidize energy companies. They are operating renewable power plants, which have intermittency issues, they should be solving this problem. I don't see any reason why I should be part of their problem of their own making.

They solve their problem by paying me money. I'm fine with that. You don't have to get paid if you don't want to.

Re: EVs Are Essential Grid-Scale Storage

#136

Post by schiffern »

neallindsay wrote: post #109
dmurray wrote: post #74

Earlier quoted context omitted.

> A 60kwh car battery might cost $10k, and allow 2000 charge cycles. So each kwh cycled into and out of the battery costs 8 cents. If you can really treat the whole cost of the battery as X cents per charge cycle, disregarding the lifetime of the car/battery, this won't work at grid scale. Someone else will build a storage facility that just charges and discharges batteries, and they will outcompete rational EV owner…

"X cents per charge cycle" is a bit simpler than the reality. The actual wear cost of charging/discharging a big EV battery is cheaper in the middle and more expensive at the extremes. I already have to own a car for short trips most days and an occasional long trip. And when I'm not going on a long trip I have a lot of extra battery capacity that I can rent to the grid at extremely low (additional) cost to me. A ded…

I took their numbers only as a simplified illustrative example to teach the idea.

A real deployed algorithm would estimate the "degradation cost curve" over the entire DoD, and stop charging when total (fully-considered) costs exceed revenue.

Re: EVs Are Essential Grid-Scale Storage

#137

Post by shagie »

ben-schaaf wrote: post #134
shagie wrote: post #76

Earlier quoted context omitted.

> And even for grids where blackouts are infrequent, if your car can serve as large UPS for your house (combined with a large capacitor to keep the power stable), such functionality in the charger may be worth the cost of the hardware for many people. (Bringing the number of units up and hence the cost per unit down over time.) https://www.tesla.com/sites/default/files/downloads/tesla-ne... > Warranty Limitations > T…

> All model year 2013 and newer Nissan Leafs are approved for use with the FE-15 bidirectional charger, and the automaker states that battery warranties will not be affected. https://www.theverge.com/2022/9/12/23349971/nissan-leaf-bidi...

https://cleantechnica.com/2022/09/09/a-nissan-leaf-can-power...

> Ideal for companies with fleet vehicles, the Fermata Energy Demand Charge Management application, along with the FE-15 charger, continuously monitors a building’s electrical loads, and may draw on the Nissan LEAF’s energy to provide power to the building during more expensive high-demand periods. In states with utility demand response programs, bi-directional-enabled Nissan LEAF vehicles (MY2013 and later) are able to safely send energy stored in the battery to the grid during peak energy demand times, such as in summer months.”

> The downsides to V2G tech are that it must degrade your battery (to some extent or another) to be discharging and charging more frequently, and it leaves your battery with less charge at times when you may wish you hadn’t discharged at all. Some people will always take that tradeoff, though, and it is great to simply have an option on the table for consumers who really want V2G tech. Stay tuned and watch this space.

> The article on the Fermata Energy/Nissan announcement is not quite correct. It’s for commercial use only – not residential. The Nissan-approved FE-15 bidirectional charger is available for commercial and government fleet owners. https://www.fermataenergy.com/fe15-sales

---

The other part is that this is grid supplemental charging where there is already a steady main current to be matched. If you are using it to power an island (home or similar disconnected from the grid), it is a different situation and would require completely disconnecting from the grid with safety cutouts to make sure that when the grid comes back on that the systems are not out of phase and damage equipment.

Grid storage is a different (and arguably easier) problem than home backup in the case of a blackout.

Re: EVs Are Essential Grid-Scale Storage

#138

Post by dahfizz »

j245 wrote: post #126
dahfizz wrote: post #72

Earlier quoted context omitted.

> So what are the realistic options? Maybe the utility companies could do their job and provide a reliable electricity source, instead of outsourcing it to customers.

> Companies could do their job This is quite a naive view of how the world works. Their actual “job” is to make the most amount of money possible. A realistic option has to be one that is both technically superior and something a company is incentivised to do.

> Their actual “job” is to make the most amount of money possible.

That is generally true, but not of quasi-public utility companies. The government controls the price utilities charge, and could force them to invest in storage.

Re: EVs Are Essential Grid-Scale Storage

#139

Post by schiffern »

trashtester wrote: post #46
londons_explore wrote: post #25

Earlier quoted context omitted.

Luckily, any degradation can all be predicted ahead of time. A 60kwh car battery might cost $10k, and allow 2000 charge cycles. So each kwh cycled into and out of the battery costs 8 cents. So a smart algorithm can decide it's worth draining the battery back into the grid if the profit to be made is more than 8 cents. Buuuut ... Delaying charging till later is free. So another car owner's car might see on the futures…

> Buuuut... Delaying charging till later is free. This functionality is already there. > So each kwh cycled into and out of the battery costs 8 cents. This is quite much. If you add other infra overhead, feeding power back into the grid is not going to produce much revenue for the individual unless the selling price is maybe 20 cents above the price when charging. On the other hand, something that MAY make more sense…

>This functionality is already there.

Simple delayed charging with a timer is common, yes. The grid interactivity part? Much less so.

The few V1G pilot programs out there have been very encouraging.

>better to use dedicated batteries as part of the grid itself than to use car batteries

Fortunately, it's not an either/or. We can better optimize the total system cost by doing both.

Re: EVs Are Essential Grid-Scale Storage

#140

Post by staringback »

londons_explore wrote: post #25
Yizahi wrote: post #10

Aren't people wary about using their very expensive car batteries for the grid? E.g. imagine you plug in your phone for the night, but instead of a single top up change it is now constantly discharging and charging again. Lifetime of pocket sized batteries is not too great even now, and in such scenario they will go bust 2-3 times faster, in year instead of 3 or so. Also discharge swings would be probably much bigger…

Luckily, any degradation can all be predicted ahead of time. A 60kwh car battery might cost $10k, and allow 2000 charge cycles. So each kwh cycled into and out of the battery costs 8 cents. So a smart algorithm can decide it's worth draining the battery back into the grid if the profit to be made is more than 8 cents. Buuuut ... Delaying charging till later is free. So another car owner's car might see on the futures…

Let's hope you don't need to go anywhere urgently in the middle of the night... oops not enough battery to make it!
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