DC charging stations sometimes have batteries on site so that they can charge up from the grid and then deliver bursts of power from the batteries during charging. Apparently this is often worth it to avoid the high demand fees that utilities charge when you draw a lot of power at once.
I assume this will become more ubiquitous as charging speeds continue to increase.
(You're right that a megawatt is a high power draw in the context of normal household electricity usage, but keep in mind that if you can pump ten gallons of gas in a minute you're effectively drawing the equivalent of something like 20MW, so in the context of vehicle refueling it's not so crazy.)
> but keep in mind that if you can pump ten gallons of gas in a minute you're effectively drawing the equivalent of something like 20MW, so in the context of vehicle refueling it's not so crazy
If 15 Teslas pass through a stretch of road per minute with full 100kWh battery packs, you could also describe that as 90MW of current, but it's also not really.
Yes. One of the usual YT channels had this interesting picture. Gas mileage is miles per gallon. Or in this case, do it the European way: l/100km. The unit of that is an area. Typically a rather small one, ca 0.1mm^2.
That's the area of a trench you have to dig along your path if you want to supply your car from the trench instead of your gas tank.
When charging, the Tesla shows you a little miles per hour figure (how many miles of range you gain per hour of charging) and it can often reach 1000 or so on the super chargers I use frequently. It’s fun to calculate the miles per hour of gas (around 12,000).
This is true. Though the electric batteries do have the advantage of having already paid the "thermodynamics tax". Some of the energy in gas will go towards heat losses; energy that cannot be converted to movement.
But that thermodynamic tax is a negative in very cold climates where the electric vehicle will see a major change in total travel distance compared to ICE.
Heat pumps make it more efficient to convert the fuel to electricity at a big, efficient power plant, and then to heat, than to burn the fuel itself for heat in an internal combustion engine (or at home for that matter)
Yes, but note that this type of 'overall thinking' sometimes has interesting consequences. Eg overall globalization raises wages, but it decimated rural economies in the west and caused a lot of social harm leading to the rise of populism.
The odometer shock that will start hitting low wage earners forced to migrate to EV may have less important but similarly surprising unintended consequences.
The problem is obvious though, isn't it? Our current infrastructure simply cannot handle a ton of EV's all wanting to charge up all day long - as is done currently with gas stations all over the country.
It'll take decades to bring our infrastructure up to where it needs to be to support this - yet people act like we're already there. Some states still struggle just to keep the lights on during major parts of the year...
The load is spread out in a completely different way than gas, because 100% of gas cars get gas at a station, while 80% of people with EVs slow-charge at home (or work or whatever). Fast chargers are for road-trips only.
Obviously, if we're going to move to cleaner energy we will need infrastructure investment. Worrying that it's not already there makes no sense. The demand for improved electrical infrastructure will be a forcing function. There's no need to wait for it. But again, most charging isn't fast charging and likely never will be.
(Charging for apartments and stuff still has a bit of a way to go, so sometimes those people use fast chargers as part of their regular routine, but the solution to that is easy and underway: just put chargers in the apartment parking lot and/or on the streets.)
> Obviously, if we're going to move to cleaner energy
It is very unclear whether electric vehicles actually are more environmentally friendly. They sound great - but if you dig into where all the materials come from, it's shocking how externalized we've made that problem. It might be cleaner by time you get to drive it... but it's not cleaner to produce and operate, and in fact may be worse in some cases. Emissions aren't just from the tailpipe after all - yet that appears to be what most people focus on.
> Worrying that it's not already there makes no sense
It makes a lot of sense when the government (both state and federal) are pushing initiatives and incentives to force EV's into commonplace. Our infra just cannot handle it, even with trickle chargers like you've claimed. Which means it will be a net-worse experience for people, and they will resist future clean energy pushes as being disingenuous.
The major points have already been refuted by another poster. I want to just add that I can't comprehend how anyone could think taking a dump on all our lungs at every road is a good idea. In the future, people will look at it like the middle ages dumping all their human waste on the streets out their windows. In that same future, lung-related problems will nearly disappear as these toxic emissions cease to exist.
Centralizing dirty energy generation allows better regulation and control of it. It also allows converting that dirty energy to clean energy without any friction from consumers. You can power an EV using coal. You can also power it using nuclear or solar. What options to power a gasoline car do you have?
EVs also force the improvement of the power grid to be more resilient and modernized, instead of stagnant and lazy, to be sucked dry.
It is shocking how externalized the costs are with our reliance on oil -- technological stagnation, toxic fumes everywhere, literally heating of the entire planet, funding of backwards authoritarian governments, and the NOISE! Only a fool would support the continued usage of oil when EVs exist now.
> It is very unclear whether electric vehicles actually are more environmentally friendly.
No, it is extremely clear. Including manufacturing they are cleaner than gas cars. And they will get better over time as the grid greens and as batteries become made out of more recycled materials. The batteries are 99% recyclable into new batteries and so there is a point where new materials never need to come out of the ground. Also, if you only focus on the most pressing thing, greenhouse emissions, the story is even better.
> Our infra just cannot handle it
Yes it can. There have been ~zero issues with the grid as a result of EV adoption.
So previous commenters have presented some facts for you. But since human brains tend to reject facts when they don't match their world view, I am curious - have you changed your stance, or continue to believe what you said?
Majority of US homes do not have an abundance of 240v outlets - meaning your 40 hour charge is a non-starter for everyone but those in high income brackets and ability to modify their homes (ie. non-renters).
It's only the highest peaks of demand that cause problems for the grid. EV charging, on average, is one of the least time sensitive loads there is. People charge in the middle of the night when its cheap.
> People charge in the middle of the night when its cheap.
Why is it cheap in the middle of the night? Because there's near zero demand.
Fast forward 10 years and everyone has 1-2 EV's to charge each night. Is there zero demand still? No... and now it's expensive to charge at night.
People really need to be realistic about these things. Pretending these issues do not exist only harms EV adoption. People buy expensive EV's and find out it's a major PITA to keep it running, it's expensive to charge, it takes forever to charge, etc.
> People buy expensive EV's and find out it's a major PITA to keep it running, it's expensive to charge, it takes forever to charge, etc.
Very few people have done this. After people buy EVs, most of them learn how easy it is in comparison to ICE cars.
You're very optimistic if you think "everyone will have 1 or 2 EVs" in 10 years time. New ICE cars will still be available until at least 2035. Not accounting for non-new cars.
You'll never need that much power at home. Level 2 AC 240V 30-50A is fine for overnight charging.
The way Tesla Supercharging works is by using a large bank of batteries for the heavy bursts of power draw (>100kW) during the initial periods of charging when the battery is warm and at a low percent. The batteries at the station are backfilled with less current from the grid in the background during periods of low use. At least that is how I understand it.
but yeah, maybe trucks with huge batteries may be able to take advantage of it down the road.
I don't know about the NA, but that is definitively not the case for most superchargers (or any other brand of fast chargers, for that matter) in Europe. Batteries are expensive so this is only done in very special cases. I know they've used battery banks at some of the electrical ferries in Norway, simply because the cost of running new high-voltage power lines was deemed more expensive and the schedule of the ferries makes it very easy to model.
Power grids are quite large, so any fluctuations across the grid is going to be minimal. They are quite good at modeling these things, otherwise we'd have rolling blackouts quite often. For homes it's the last mile that's usually the biggest limiting factor.
But I agree with what you said, for /most/ people anything more than 2kW (so 240V/10A) is more than enough to charge up overnight. A perk with CCS2 is the support for 3-phase power delivery. With very simple wiring and some smart(-ish) electronics you can opportunistically deliver around 11kW to a single car, or divide it with other house appliances or other cars. It's fairly common with 400V TN-system in some parts of Europe, which makes the support of 3-phase in CCS2 very handy.
I don't think most NA superchargers have batteries either, though some definitely do, but I believe going forward they are likely to have "powerpacks" to support pickup and semi truck charging.
Most people don't drive 500km per day, the average is closer to 50 or so. So on average, you could easily top of your battery pack on 240V/10A circuit. That would be around 10kWh, which you'll do in 5 hours. Double the average and you'll still be topped up next morning.
Many people often travel regularly, like I do to visit family 150mi away. It would sure be nice to be able to charge while I'm at their house at a rate that would fill me back up. Range and charging speed matters, y'all shouldn't be just hand waving it away.
It's not being hand waved away. You're just constructing scenarios that most people owning an electric vehicle will agree is such a non-issue that it's not really worth debating. There are plenty of fast chargers to fill the gaps.
Many people travel regularly. Many people don't. That's how we ended up on the average being 50km.
> There are plenty of fast chargers to fill the gaps.
Definitely not on the route to where my family lives. I checked last year when I was looking at EV, there's like a single L2 charger at a hotel on the whole route. I expect it will be several more years before the millions of us with family in the country can reasonably buy an EV.
I don't think I've ever claimed that EVs are suitable for everyone right now or that the infrastructure is there to fully replace every single scenario. The point is still that most people can have most of their needs met by a simple wall plug for charging.
Chances are that you don't even need to charge on your 150 miles trip. Most modern BEVs will be able to take you anywhere from 300-350 miles on a single charge. In your scenario you could literally do a round trip and have a comfortable level of charge when you get home again.
As a new Model 3 owner, I've been looking into how to do this.
The solutions aren't particularly nice, there's the Quick220, a device which does all the safety checks of manually combining 2 circuits on opposite phases so you can actually get 12A at 240V. But it requires 2 circuits on opposite phases, neither with GFCI (which most outdoor outlets have).
Second option is a NEMA14-50 extension cable, which obviously carries it's own risks but if there's a dryer outlet on a 30A breaker, that gets you 24A at 240V.
But yes, either solution requires a bunch of bulky cords running out the door, and the assumption that the houses' electrical wiring was done properly and is in good condition.
So far the only less-invasive alternative is hoping they have a 20A circuit somewhere convenient, rather than just the kitchen plugs, then you can get an extra 33% charging speed (16A @ 120V) with the proper 5-20 adapter.
I think the more practical solution will be private plug-sharing, there's already a few apps and startups advertising I can earn money by allowing others to book my home charger, and a proper home install can do 11kw.
It could also be useful at homes to regulate power (assuming the grid connections/solar/batteries were all available), allowing you to charge faster when power is cheap, and pull way back (or even backfeed) when power is expensive.
But it's mainly to try to get EV fillups to be gas-station like. If you can recharge a Tesla to 80% in 5 minutes, you've won.
It is indeed totally insane, but this is what is being worked on, not necessairly for cars but trucks and semi trucks for example that have much larger batteries than a car. Already to achieve 250+ kW charging stations have to have huge cables and watercooled connectors, here's one such installation I saw some years ago https://i.imgur.com/BpG4QAa.jpg and an example of a cooled connector for 0.5 MW https://www.phoenixcontact.com/en-ca/products/dc-charging-ca...
I assume the next jump in power will come from voltage. A Model 3 pulls ~600A when charging at 250kW, because it's relatively low voltage. If they alter the charging design to accept 800 or 1000V we could see over half a MW without a change in cable design. But I'd guess at this point that would be moot because the cell charging rate is the real limit anyway.
Yes Porsche has started with this, they have ~800 V batteries, as you said batteries themselves are the practical limit at the moment but both larger batteries (as with trucks) and new battery technology can help to lift that limit. There are enough engineering challenges at 1000 A I don't think we will see higher currents than that for a while!
Migrating to higher voltage doesn't do anything to charge batteries faster. The only advantage is that you can decrease the size of the cabling since current goes down. On the other side though, you need to move all drive circuitry, motors, etc, to handle higher voltage architecture, which may end of costing more overall.
So, you add the complexity of having to have a way to switch between 400V and 800V safely, which costs some amount of money, and the only advantage then is the cabling from the battery to the charging port can be thinner? That really doesn't seem like much savings, and if anything might cost more. The run from the charging port to the battery should already be really short.
Electric cars are almost 4X as efficient as a gas car, so 1MW of electricy and 4MW of gasoline are roughly equivalent in miles added per minute.
OTOH the only batteries that can absorb 1MW of electricity are those in some Class 8 trucks, and Class 8 diesel trucks are usually filled with pumps a lot faster than a standard gas station pump.
It's a useful comparison for how long it takes to refuel a vehicle, but "moving a liquid storing chemical potential energy through a tube" and "move electricity through a wire [and re-store it as electro-chemical potential energy]" are two such radically different activities that it glosses over a lot to equate the two.
1MW is 20x the maximum draw of a standard house, and 800x the average draw of a US house. The hydro plant down the road generates 5MW.
It just sounds crazy to plan to pull that much power charging a car at a time.