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EVs Are Essential Grid-Scale Storage

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Re: EVs Are Essential Grid-Scale Storage

#121

Post by jononomo »

When the Ford F-150 Lightning came out I was interested to learn that the battery was powerful enough to power a standard American house for over two days.

This made me wonder why new houses don't come with a battery built in, thereby making power outages obsolete. A battery that could withstand a 48-hour power outage without the occupants even realizing anything had happened seems like it would give the power grid a lot more flexibility and could be a real lifesaver in the case of natural disasters and other emergency situations.

Adding a battery would probably add $10k to the cost of a house, but for a home that costs $400,000, that is only 2.5% of the price. A smaller battery that just provided 12 hours of power might only cost $3k.

I'd be interested to hear from knowledgeable people what the downsides to this idea are. I suppose the battery might degrade over time, and it is likely it would go for several years at a time without being called upon.

Re: EVs Are Essential Grid-Scale Storage

#122

Post by TheLoafOfBread »

gwbas1c wrote: post #119

This really only makes sense for short-term, emergency storage: IE, if a major power plant suddenly goes offline, calling on EVs to push power back into the grid for 10-60 seconds. This is enough time for things like pumped storage and quick start generators to come online. (It also wouldn't cause noticeable wear.) Likewise, even disabling charging for a short-term, emergency 10-60 second period might be more practic…

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

Re: EVs Are Essential Grid-Scale Storage

#123

Post by schiffern »

noptd wrote: post #120
greenthrow wrote: post #62

Earlier quoted context omitted.

We are not talking about multiple 0-100% cycles daily. The places where pilot programs have been run always left the car with some amount of charge so it can be driven, and you don't normally charge NMC car batteries to 100%. Vehicle batteries have 8 year 100k mile warranties today, and those manufacturers who have spoken on this topic have said that utilizing your battery as grid storage will not violate the warrant…

Excluding Tesla: https://news.ycombinator.com/item?id=34518608 Perhaps you should do more research before ending a comment on such a condescending remark next time.

V1G to the rescue!

Existing Tesla cars can do V1G (grid-adaptive charging), but not V2G.

https://news.ycombinator.com/item?id=34518188

Re: EVs Are Essential Grid-Scale Storage

#124

Post by theluketaylor »

danuker wrote: post #44
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…

It worries me that if industrial-purpose batteries cost the same and have similar degradation, grid services will also decide not to charge/discharge if the profit is less than 8 cents. This tells me that Li-Ion batteries are far from the ideal medium for grid storage.

Most cars use NCA or NMC chemistry which has 500ish cycles. Grid storage will soon use LFP which is cheaper to begin with and has 5000+ cycles. It has a lower density than other chemistries and very poor cold weather performance, making it less ideal for vehicles (though Tesla is using it in the standard range model 3 now). Those downsides don't matter for grid storage and really change the economics of charge/discharge.

Re: EVs Are Essential Grid-Scale Storage

#125

Post by bryanlarsen »

dmurray wrote: post #74
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…

> 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…

Power has two big costs: generation and distribution. Once rooftop solar power is below the cost of distribution it doesn't matter how much it costs to generate power; rooftop solar is always going to be cheaper.

That milestone has been hit in some places Australia already.

Re: EVs Are Essential Grid-Scale Storage

#126

Post by j245 »

dahfizz wrote: post #72
coffeebeqn wrote: post #63

Earlier quoted context omitted.

It is gimmicky but the batteries in EVs are really big and especially in the US everyone has a car. I don’t see a large amount of houses getting a 30-70kWh battery unless they install rooftop solar. So what are the realistic options ? Other than large infrastructure spend to get grid batteries which is probably what will happen in the end

> 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.

Re: EVs Are Essential Grid-Scale Storage

#127

Post by jackmott »

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…

[dead]

Re: EVs Are Essential Grid-Scale Storage

#128

Post by manholio »

DeRock wrote: post #55
manholio wrote: post #11

This is never going to happen at scale. Energy is fungible: one cannot compete on "quality" of energy, just on price, a kWh is a kWh and the provider with the cheapest energy will always win in the marketplace. So this means any EV owner looking to make a profit is competing against large scale industrial storage entities that: - have large mass and purchasing power, optimizing their battery purchasing and operationa…

My electricity cost currently is split around 1/3 generation (~10¢/kWh) and 2/3 distribution (~20¢/kWh). If the power from this scheme can avoid most of the costly distribution, eg. I use it directly in my house and neighborhood, then it’s an economic win. This would be true even if the centralized generation was free.

It can't, because the distribution fee is an amortized cost of having distribution infrastructure built. Since that infrastructure still needs to exist regardless of where you get your energy (and in fact needs to be upgraded to handle bidirectional consumer/producers), EV storage won't bypass it regardless of where the EV and the consumer is physically located.

If you consume what you store, then you will charge up at low (production prices + distribution fees) for the times when (production prices + distribution fees) are high. The second term is constant so you are arbitraging on production prices.

Re: EVs Are Essential Grid-Scale Storage

#129

Post by bryanlarsen »

svggrfgovgf wrote: post #56
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…

People value things differently. You'd have to pay me way more than the 8 cents/kwh it cost me to use my battery. I'd want to be heavily compensated for the inconvenience of replacing the battery or car prematurely.

If I had a LiFePo4 battery that's good for 750,000 km I'd be willing to accept less than 8c because there's no way the rest of the car is going to last 750,000 km.

Re: EVs Are Essential Grid-Scale Storage

#130

Post by schiffern »

TheLoafOfBread wrote: post #122
gwbas1c wrote: post #119

This really only makes sense for short-term, emergency storage: IE, if a major power plant suddenly goes offline, calling on EVs to push power back into the grid for 10-60 seconds. This is enough time for things like pumped storage and quick start generators to come online. (It also wouldn't cause noticeable wear.) Likewise, even disabling charging for a short-term, emergency 10-60 second period might be more practic…

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?

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