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EVs Are Essential Grid-Scale Storage

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Re: EVs Are Essential Grid-Scale Storage

#181

Post by guruz »

ceejayoz wrote: post #131
gwbas1c wrote: post #96

Earlier quoted context omitted.

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.

You might be at work (away with car) while the midday sun is filling your home battery.

Re: EVs Are Essential Grid-Scale Storage

#182

Post by mercutio2 »

punnerud wrote: post #89
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…

This already exist in Norway with the company Tibber, that have more than 400.000 users. They do just that, let you connect your EV so they adjust the charging and guarantee a lower price. The market they can buy and sell this capacity is called an “aggregator”, and they can earn more money on this then selling just power.

This is “let a large entity suck up much of the arbitrage value, with a small fraction going to you”, and already exists in most countries.

Seems quite different from “your household is an autonomous actor and you get almost all of the arbitrage value of reducing peak consumption”, which would be a radically different system (but ignores who’s going to pay for distribution, which is getting closer and closer to being the dominant cost of the grid).

Re: EVs Are Essential Grid-Scale Storage

#183

Post by [deleted] »

foobazgt wrote: post #151
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…

V2X (vehicle to grid, home, or load) is pretty new, but there are some vehicles out there with it. Tesla is not one of them. They seem to be more focused on solving storage with powerwall. I don't know where that's good or bad, but I do wish I could use my Tesla to jump another dead EV.

[deleted]

Re: EVs Are Essential Grid-Scale Storage

#184

Post by RetpolineDrama »

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…

Well they're paying you. In the recent tesla powerwall virtual grid experiment people were printing like $60/day

Re: EVs Are Essential Grid-Scale Storage

#185

Post by goodpoint »

college_physics wrote: post #60

This feels gimmicky and fragile. If distributed / decentralized storage is required (sounds like a good idea overall) it is surely better to have stationary installations, with larger batteries and connectivity optimized for that purpose, not using the EV batteries currently developed for moving these two-ton exosceletons to random places... In fact you want to have the option to significantly reduce EV usage as othe…

> This feels gimmicky and fragile

If anything is very much anti-fragile. Decentralized batteries would only make the grid more resilient both to outages and overloads.

Re: EVs Are Essential Grid-Scale Storage

#186

Post by goodpoint »

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.

No. You are going to charge up for longer trips e.g. on holidays.

Re: EVs Are Essential Grid-Scale Storage

#187

Post by babypuncher »

This sounds like a great way to destroy the longevity of my battery.

If they want to use my car as grid storage, then the power company better pay to replace my battery, plus compensate me for the added inconvenience of having to perform that maintenance far more frequently.

Re: EVs Are Essential Grid-Scale Storage

#188

Post by csours »

raxxorraxor wrote: post #2

I don't understand the discrepancy between EV kWh and house battery kWh. Some cars have > 100 kWh capacity. Why do I pay > 1000$ per kWh for a house battery? At some point it is cheaper to just buy a car, even if you would never drive it. A Tesla Powerwall has 13 or so kWh? Why don't they use the car battery with nearly 10 times as much capacity? It is just unit prices that are far better for cars? Is the charge/disc…

My guess is supply constraints. Tesla would rather sell cars than Powerwalls; other suppliers can't make a dent in the market because EVs are slurping up all the capacity at every level of the supply chain. This really is only a guess though.

Re: EVs Are Essential Grid-Scale Storage

#189

Post by jakewins »

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…

Thank you for posting this. This focus on V2G is nuts.

We move huge volumes of our residential portfolio every day just setting EV schedules - enough that our total residential profile peaks at market bottom price hour nearly every day, even in winter with lots of ”dumb” heating load.

Re: EVs Are Essential Grid-Scale Storage

#190

Post by torpfactory »

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…

You're making very aggressive assumptions about amount of use the EV battery would be subject to, to the point of this being a straw man. You're right that people wouldn't agree to have their expensive EV battery trashed by multiple 0-100% discharge cycles daily. You wouldn't get any takers if that was your offer.

A more reasonable expectation is that people would lease a portion of their capacity. Say 20% for argument sake. You could even place other limits on it "never below 50% and above 90% on weekdays". In this example the power company gets to use between 50% and 90% state of charge in your battery on weekdays and pays you a small fee or other compensation in return.

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