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How BYD got EV chargers to work almost as fast as gas pumps

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Re: How BYD got EV chargers to work almost as fast as gas pumps

#231

Post by atoav »

torginus wrote: post #225

The fundamental problem of high-wattage charges (say 500kW), isn't to deliver power from the charger to the car, but that there needs to be crazy amounts of grid capacity to support them. A house has like 10kW peak sustained power consumption (an apt even less), which it rarely reaches, so a park of these fast chargers need the same infrastructure as a small town. These loads are so huge Cities like Beijing have stro…

As an certified electrical engineer, this is certainly a problem. The main issue is of course how much copper is burried underground and how big transformer capacity is.

The first solution is of course to try avoiding farst charging if possible by charging at home or at work over hours if possible. A faster charge will have to be a more expensive charge. Another solution that could ease things a little is to spread the load on the grid over time by drawing it from some local source (e.g. battery) Imagine a gas station has a beefy energy storage from which it draws the current in short blasts while the battery itself draws it much more spread out over hours.

This is essentially how it is done in much smaller scales (in terms of time, energy and actual physical size) on printed circuit boards using capacitors. If you'd draw the current all the way back from the power supply any bursty load would affect the voltage on the power supply and thus show up in other psrts of the circuit.

But in the end more electrical energy demand by mobility will lead to more electrical demand, period. And as you rightly pointed out that means more infrastructure, more copper in the ground, bigger transformers, more powerplants.

Re: How BYD got EV chargers to work almost as fast as gas pumps

#232

Post by expedition32 »

torginus wrote: post #225

The fundamental problem of high-wattage charges (say 500kW), isn't to deliver power from the charger to the car, but that there needs to be crazy amounts of grid capacity to support them. A house has like 10kW peak sustained power consumption (an apt even less), which it rarely reaches, so a park of these fast chargers need the same infrastructure as a small town. These loads are so huge Cities like Beijing have stro…

In the Netherlands the energy network is undergoing a huge upgrade because of wind and solar- technologies nobody predicted in the 1970s.

Things used to be simple: big power station makes energy and lines transport it to every home. Now you have vast wind farms far out on the North Sea and millions of buildings have solar panels. And to top it all off electricity replaces gas for heating and cooking.

We're gonna need bigger cables.

Re: How BYD got EV chargers to work almost as fast as gas pumps

#233

Post by markus_zhang »

beeflet wrote: post #143
markus_zhang wrote: post #43

Earlier quoted context omitted.

There might be no industrial long term planning, but I think it’s because the US operates in a different mode — financial (late) Capitalism.

That's the problem with late capitalism- we need an economy that makes people want to get up and early.

I think it's difficult to turn around, unless the mud is cleansed -- but most likely the mud doesn't want to be cleansed so it would rather take the whole pond with it.

Re: How BYD got EV chargers to work almost as fast as gas pumps

#234

Post by Shitty-kitty »

DroneBetter wrote: post #228
KolmogorovComp wrote: post #217

Earlier quoted context omitted.

> 99.9% of use cases of EVs can charge at home/work/shop This is yet again a very US-centric view where you assume people are living in house with a garage.

"home" can be substituted for "place where car resides when owner is at home" without meaningfully changing the point

In NYC that would be the street. The great conundrum of ev's. People that have access to home-charging, worry about range. The one's that mostly sit idling in traffic, don't have access to charging.

Re: How BYD got EV chargers to work almost as fast as gas pumps

#235

Post by cromka »

torginus wrote: post #225

The fundamental problem of high-wattage charges (say 500kW), isn't to deliver power from the charger to the car, but that there needs to be crazy amounts of grid capacity to support them. A house has like 10kW peak sustained power consumption (an apt even less), which it rarely reaches, so a park of these fast chargers need the same infrastructure as a small town. These loads are so huge Cities like Beijing have stro…

Sorry, but I think you're wrong on your concern: in China they specifically fix this issue with buffer batteries. From grid perspective, charging is no different than with regular, slow charging stations. You can still limit their capacity (as in cars that can be charged per 24h), the difference here is you can charge quickly.

This is a good compromise for the time being while the grid catches up with demand.

Re: How BYD got EV chargers to work almost as fast as gas pumps

#236

Post by torginus »

expedition32 wrote: post #232
torginus wrote: post #225

The fundamental problem of high-wattage charges (say 500kW), isn't to deliver power from the charger to the car, but that there needs to be crazy amounts of grid capacity to support them. A house has like 10kW peak sustained power consumption (an apt even less), which it rarely reaches, so a park of these fast chargers need the same infrastructure as a small town. These loads are so huge Cities like Beijing have stro…

In the Netherlands the energy network is undergoing a huge upgrade because of wind and solar- technologies nobody predicted in the 1970s. Things used to be simple: big power station makes energy and lines transport it to every home. Now you have vast wind farms far out on the North Sea and millions of buildings have solar panels. And to top it all off electricity replaces gas for heating and cooking. We're gonna need…

Imo one of the biggest wins of renewables + battery is you can skip most of that infrastructure - you can have solar panels on your roof, on the edge of town, and you can skip most of expensive transmission infrastructure.

Re: How BYD got EV chargers to work almost as fast as gas pumps

#237

Post by doubled112 »

Shitty-kitty wrote: post #234
DroneBetter wrote: post #228

Earlier quoted context omitted.

"home" can be substituted for "place where car resides when owner is at home" without meaningfully changing the point

In NYC that would be the street. The great conundrum of ev's. People that have access to home-charging, worry about range. The one's that mostly sit idling in traffic, don't have access to charging.

The ‘burbs truly are the worst of all worlds.

Some of the homes in my neighbourhood have 2 cars in the driveway and another two on the street.

They all move regularly. Walkability is terrible. Public transit is iffy. People have to get places on time.

Re: How BYD got EV chargers to work almost as fast as gas pumps

#238

Post by torginus »

atoav wrote: post #231
torginus wrote: post #225

The fundamental problem of high-wattage charges (say 500kW), isn't to deliver power from the charger to the car, but that there needs to be crazy amounts of grid capacity to support them. A house has like 10kW peak sustained power consumption (an apt even less), which it rarely reaches, so a park of these fast chargers need the same infrastructure as a small town. These loads are so huge Cities like Beijing have stro…

As an certified electrical engineer, this is certainly a problem. The main issue is of course how much copper is burried underground and how big transformer capacity is. The first solution is of course to try avoiding farst charging if possible by charging at home or at work over hours if possible. A faster charge will have to be a more expensive charge. Another solution that could ease things a little is to spread t…

Ah thanks for the expert opinion. I used to be an EE, but I've not been working in the field for a long time

Forgive me, but afaik you can't really run truly high voltage AC lines underground - the main issues are electrical arcing and capacitive ground coupling, which leads to losses. HVDC has its own issues as well, mostly having to do with electrolysis, and it being crazy dangerous.

I mean, you can, but it's going to be very expensive.

By the way, have there been studies of what a 100% EV society's infrastructure look like, especially in countries without access to cheap and abundant renewables? I feel it's going to be quite a challenge, and would only make sense economically as part of a broader reindustrialization effor (which for the record, I support).

As for batteries, I think solar/wind require those anyway, and if a solar farm is backed by a huge battery bank, those can probably supply these ludicrous kWs these chargers would need, but transmission is going to be a challenge.

I would love to read something that would go in depth on how we would support a renewable based grid that also supports powerful fast chargers, as this I feel this needs to be a part of a society-level project, and I'm growing tired of these 'China's building better electric chargers!!!'-style alarmist articles.

Re: How BYD got EV chargers to work almost as fast as gas pumps

#240

Post by torginus »

cromka wrote: post #235
torginus wrote: post #225

The fundamental problem of high-wattage charges (say 500kW), isn't to deliver power from the charger to the car, but that there needs to be crazy amounts of grid capacity to support them. A house has like 10kW peak sustained power consumption (an apt even less), which it rarely reaches, so a park of these fast chargers need the same infrastructure as a small town. These loads are so huge Cities like Beijing have stro…

Sorry, but I think you're wrong on your concern: in China they specifically fix this issue with buffer batteries. From grid perspective, charging is no different than with regular, slow charging stations. You can still limit their capacity (as in cars that can be charged per 24h), the difference here is you can charge quickly. This is a good compromise for the time being while the grid catches up with demand.

Batteries only help with peak loads, they also cost money and wear out. Let's do some math - a 10 car 500kW charger, with a ~30% occupancy, would draw a constant 1500kW from the grid, if we calculate 3kW average for a household(which is high), that would be the equivalent of 500 households.
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