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EVs Are Essential Grid-Scale Storage

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Re: EVs Are Essential Grid-Scale Storage

#171

Post by greenthrow »

Gordonjcp wrote: post #168
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…

How far down do they discharge the battery, then? Like, how much range would you expect to have at the deepest part of the discharge cycle?

This is something pilot programs are helping to figure out. The ideal case is the driver can set minimum discharge as they can set a maximum charge (that's how it works on the Ford Lightning.) on top of that many EVs have the ability to set a departure time and the vehicle will ensure it is charged to your maximum level at the departure time.

Re: EVs Are Essential Grid-Scale Storage

#172

Post by coding123 »

discordance wrote: post #4
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…

$300/kWh for home storage is readily available. E.g. https://signaturesolar.com/eg4-ll-lithium-battery-24v-200ah/

Those 5kwh "server" batteries are overpriced compared to prismatic cells and a bms.

Re: EVs Are Essential Grid-Scale Storage

#173

Post by cogman10 »

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 will now see multiple 0%-100% charge cycles daily.

Very much not likely.

You have to realize how big the batteries are on EVs. It isn't uncommon to have 80 or 100kWh batteries on EVs (and that number is likely to go up.). Even small batteries are around 40kWh.

Average home energy consumption is 30kWh per day in the US. Meaning even for a small battery you are looking at a single extra cycle per day at most. However, if you are pairing your car charging with home solar then you are looking at a more ideal charge/discharge (Possibly keeping the car between 40 and 80%)

Re: EVs Are Essential Grid-Scale Storage

#174

Post by cogman10 »

schiffern wrote: post #139
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…

>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.

We really just need a standard. The j1772 includes data lines. V2G is would literally be just controlling when the cars battery is connected to the charge circuit.

Re: EVs Are Essential Grid-Scale Storage

#175

Post by Mrdarknezz »

pornel wrote: post #165
Mrdarknezz wrote: post #105

This seems like a massive waste of energy, why not just produce the amount of energy we need?

The demand for energy is highly variable. Without storage, the production capacity has to be overbuilt to match the peak demand, and then sit underutilized for the rest of the day. Even with just fossil fuels, it's preferable to build a smaller power plant that runs 24/7 than invest bigger money in a bigger power plant and then operate it only some of the time. See "duck curve".

No you don't have to overbuild? Just build enough load following.

Storage will waste massive amounts of energy through conversion

Re: EVs Are Essential Grid-Scale Storage

#176

Post by sokoloff »

iso1210 wrote: post #81
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…

This does work today at grid scale, people use their home batteries (either on wheels or not) to charge/discharge to the grid in the UK all the time. If someone builds that storage facility to do it commercially then great. > rooftop solar can't exist without special subsidies Yet it does

There are special subsidies for rooftop solar here in the US (Solar Investment Tax Credit). Are there not subsidies for solar where you live?

https://www.seia.org/initiatives/solar-investment-tax-credit...

> The solar Investment Tax Credit (ITC) is one of the most important federal policy mechanisms to support the growth of solar energy in the United States. Since the ITC was enacted in 2006, the U.S. solar industry has grown by more than 200x - creating hundreds of thousands of jobs and investing billions of dollars in the U.S. economy in the process.

Re: EVs Are Essential Grid-Scale Storage

#177

Post by mercutio2 »

iso1210 wrote: post #81
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…

This does work today at grid scale, people use their home batteries (either on wheels or not) to charge/discharge to the grid in the UK all the time. If someone builds that storage facility to do it commercially then great. > rooftop solar can't exist without special subsidies Yet it does

I think you may have missed the point here.

Rooftop solar is heavily subsidized almost everywhere it’s popular. Rooftop solar isn’t a good deal for utilities or their non-rooftop-solar customers.

I say this as someone who lived off the grid on solar for years; encouraging rooftop solar may have kickstarted the learning curve for the solar panel industry, and as such may have been pretty good social policy.

But it definitely owes its existence to subsidies.

These days grid scale solar makes lots of sense, rooftop solar still doesn’t (and the subsidies are now harder to defend).

Re: EVs Are Essential Grid-Scale Storage

#178

Post by onlyrealcuzzo »

londons_explore wrote: post #86
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…

Rooftop solar outcompetes solar farms because energy from a solar farm pays taxes and distribution costs before it is delivered to a user. Whereas rooftop solar energy is untaxed when it powers your laptop. > It only makes sense if the EV owner can somehow get charge capacity "for free" The EV owner has the power electronics 'for free' - ie. they have almost infinite lifespan, and just a capital cost. Additionally, t…

> Rooftop solar outcompetes solar farms because energy from a solar farm pays taxes and distribution costs before it is delivered to a user.

This depends where you live and the size/efficiency of your rooftop setup, right?

Re: EVs Are Essential Grid-Scale Storage

#179

Post by htag »

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…

> Still, though, for grid stability it is probably much better to use dedicated batteries as part of the grid itself than to use car batteries.

Why? Every kwh we can store using car batteries is a kwh of dedicated grid storage we don't need to purchase. It can increase the speed we add new storage on the grid. It is a more efficient use of lithium and other precious metals. This "smart charge" or "flex EV" is the type of incentive utility companies can push, and something that would decrease the amount of capital investments they need to make.

I can imagine a few counter arguments for why dedicated batteries are better, but nothing that convinces me. This claim that dedicated batteries are better than car batteries has little support in your comment and I would like to understand why you believe this claim.

Re: EVs Are Essential Grid-Scale Storage

#180

Post by mercutio2 »

bryanlarsen wrote: post #125
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…

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.

I don’t quite buy your argument.

If the system still depends on distribution, someone has to pay for it.

It may be that rooftop solar users will be asked to pay more for that distribution than they think is reasonable.

I’m sure not excited about my grid operator proposing a $50/month minimum for electricity, it makes my panels seem worthless. But there is logic; I was being subsidized by net metering. And in future I may have to pay a cost closer to the true cost of access to the stability of the grid.

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