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Why will public chargers be slow? We should assume that those who provide public charging services (the gas stations of the future) will be trying to optimize t

Why will public chargers be slow? We should assume that those who provide public charging services (the gas stations of the future) will be trying to optimize throughput + convenience store sales. DC fast chargers currently get you 40 miles in ten minutes[1] (that sucks!) so your extra 20 miles gets you an extra 5 minute wait. Presumably that wait can be "limited" by getting your shopping done or grabbing a bite to eat while you do it. [1]https://pluginamerica.org/understanding-electric-vehicle-charging/ https://pluginamerica.org/understanding-electric-vehicle-cha...

neogodless 7y ago
I think your example/link illustrates the point. > These stations are expensive (up to $100,000) and require more power than your house, so you’ll never have one of these in your garage. In other words, most chargers are not going to be "the best." Especially ones in less affluent neighborhoods, within a short drive (or on the way) of wherever you happen to be. Maybe it's a 10 minute round trip for a 5 minute wait (assuming no line) to charge up for and make up the extra 20 miles you need. Realistically there are best case and worst case scenarios in our future. When chargers are all as fast and convenient as gas stations, the problem pretty much goes away. Anyone that could buy an ICE car and get to the gas station when they needed to could also have a 200+ mile EV and get to (really fast) chargers when they need. If that doesn't happen (and until it does) there will be plenty of people that cannot switch to an EV without adding out-of-the-way trips to their lives, and having long wait times while they charge on less-than-the-best chargers. As I've mentioned elsewhere in the thread, forcing "shopping" or "dining out" to be a part of fueling your car is unnecessary coupling. It sounds natural, because gas stations are almost always convenience stores. Personally, I rarely eat out (especially alone!), prefer to never set foot in a convenience store, and my spouse does the majority of the food shopping. My charging time would be as equally wasted as my gasoline fill-up time.
- bsder 7y ago
  > > These stations are expensive (up to $100,000) and require more power than your house, so you’ll never have one of these in your garage. I challenge this on the cost front and on the power front. There is zero reason why a fast charger should be $100,000 other than the fact that the volume is sufficiently low that these are all hand built. The semiconductors in that thing can't possibly be $100,000 in volume. Copper is roughly $10 per kilogram--or $100,000 and you could use 10 metric tonnes--there is no way those things hold 10,000 kg of copper. As for the power, these things are probably more than 90% efficient, so they don't use any more power than the smaller ones (the load they are charging is a fixed size regardless of how fast you charge it). They may use more current, but that's the whole point! These things charge your car faster. The biggest issue with installing these at home is probably access to genuine 440V (or higher) 3 phase. And you probably get around that by making the charger the equivalent of a Powerwall--it stores the energy at normal 220 feed levels but blasts it into your car from it's own batteries as fast as it can.
  - jeffwilcox 7y ago
    Permits, load studies, switchgear components for 3-phase systems (breakers etc.) cost more, engineering costs drive this up, etc. The grid and city permitting processes weren't designed for broad "consumer" scenarios, at least basing it off of the current Seattle experience, where even Level 2 charging can be difficult.
  - hwillis 7y ago
    > The semiconductors in that thing can't possibly be $100,000 in volume. Copper is roughly $10 per kilogram--or $100,000 and you could use 10 metric tonnes--there is no way those things hold 10,000 kg of copper. I mean... yes, you're right. A better example would be that electric cars can already convert 3-phase to DC (as well as the other way), and the Tesla Model 3 can convert over 200 kW even though it comes with a motor, battery, and an entire car for far less than $100k. > As for the power, these things are probably more than 90% efficient, so they don't use any more power than the smaller ones (the load they are charging is a fixed size regardless of how fast you charge it). They may use more current, but that's the whole point! These things charge your car faster. Closer to 95%, most likely. There also theoretically are very few bad chargers (despite exceptions[1]) since most of the cost is in installation, insurance, and weather/tamperproofing. [1]: https://hackaday.com/2019/08/07/a-post-mortem-for-an-electric-car-charger/ https://hackaday.com/2019/08/07/a-post-mortem-for-an-electri...
- esotericn 7y ago
  $100K doesn't seem like that much to me. Compare to the costs of like, having a massive petrol tank under the floor with regular maintenance, lorries filling it all the time, the amount of space required for that. Maybe I'm wrong, but I imagine the cost of installing a new petrol station anywhere close to civilization would dwarf that.
deleted 7y ago
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gok 7y ago
That article is from 2011. Modern fast chargers are 2-3x faster than that, and the next generation (350 kW chargers) will cut times in half again.
- steelframe 7y ago
  > the next generation (350 kW chargers) It's not even "next generation" chargers; it's next generation EVs at this point. Nearly all new Electrify America rapid charging locations have at least one station that can do 350kW. We're just waiting for EVs like the Taycan* to be released (less than 1 month -- Sept 4th!) to be able to accept charge rates approaching that. EA is on-track to get 2,000 fast chargers at nearly 500 locations up and running by end-of-2019. *The first generation Taycan will charge at 250kW. But the infrastructure is coming online now as EV manufacturers iterate on battery pack technology to accept faster charge rates.

neogodless 7y ago

I think your example/link illustrates the point. > These stations are expensive (up to $100,000) and require more power than your house, so you’ll never have one of these in your garage. In other words, most chargers are not going to be "the best." Especially ones in less affluent neighborhoods, within a short drive (or on the way) of wherever you happen to be. Maybe it's a 10 minute round trip for a 5 minute wait (assuming no line) to charge up for and make up the extra 20 miles you need. Realistically there are best case and worst case scenarios in our future. When chargers are all as fast and convenient as gas stations, the problem pretty much goes away. Anyone that could buy an ICE car and get to the gas station when they needed to could also have a 200+ mile EV and get to (really fast) chargers when they need. If that doesn't happen (and until it does) there will be plenty of people that cannot switch to an EV without adding out-of-the-way trips to their lives, and having long wait times while they charge on less-than-the-best chargers. As I've mentioned elsewhere in the thread, forcing "shopping" or "dining out" to be a part of fueling your car is unnecessary coupling. It sounds natural, because gas stations are almost always convenience stores. Personally, I rarely eat out (especially alone!), prefer to never set foot in a convenience store, and my spouse does the majority of the food shopping. My charging time would be as equally wasted as my gasoline fill-up time.

bsder 7y ago
> > These stations are expensive (up to $100,000) and require more power than your house, so you’ll never have one of these in your garage. I challenge this on the cost front and on the power front. There is zero reason why a fast charger should be $100,000 other than the fact that the volume is sufficiently low that these are all hand built. The semiconductors in that thing can't possibly be $100,000 in volume. Copper is roughly $10 per kilogram--or $100,000 and you could use 10 metric tonnes--there is no way those things hold 10,000 kg of copper. As for the power, these things are probably more than 90% efficient, so they don't use any more power than the smaller ones (the load they are charging is a fixed size regardless of how fast you charge it). They may use more current, but that's the whole point! These things charge your car faster. The biggest issue with installing these at home is probably access to genuine 440V (or higher) 3 phase. And you probably get around that by making the charger the equivalent of a Powerwall--it stores the energy at normal 220 feed levels but blasts it into your car from it's own batteries as fast as it can.
- jeffwilcox 7y ago
  Permits, load studies, switchgear components for 3-phase systems (breakers etc.) cost more, engineering costs drive this up, etc. The grid and city permitting processes weren't designed for broad "consumer" scenarios, at least basing it off of the current Seattle experience, where even Level 2 charging can be difficult.
- hwillis 7y ago
  > The semiconductors in that thing can't possibly be $100,000 in volume. Copper is roughly $10 per kilogram--or $100,000 and you could use 10 metric tonnes--there is no way those things hold 10,000 kg of copper. I mean... yes, you're right. A better example would be that electric cars can already convert 3-phase to DC (as well as the other way), and the Tesla Model 3 can convert over 200 kW even though it comes with a motor, battery, and an entire car for far less than $100k. > As for the power, these things are probably more than 90% efficient, so they don't use any more power than the smaller ones (the load they are charging is a fixed size regardless of how fast you charge it). They may use more current, but that's the whole point! These things charge your car faster. Closer to 95%, most likely. There also theoretically are very few bad chargers (despite exceptions[1]) since most of the cost is in installation, insurance, and weather/tamperproofing. [1]: https://hackaday.com/2019/08/07/a-post-mortem-for-an-electric-car-charger/ https://hackaday.com/2019/08/07/a-post-mortem-for-an-electri...
esotericn 7y ago
$100K doesn't seem like that much to me. Compare to the costs of like, having a massive petrol tank under the floor with regular maintenance, lorries filling it all the time, the amount of space required for that. Maybe I'm wrong, but I imagine the cost of installing a new petrol station anywhere close to civilization would dwarf that.

deleted 7y ago

[deleted]

gok 7y ago

That article is from 2011. Modern fast chargers are 2-3x faster than that, and the next generation (350 kW chargers) will cut times in half again.

steelframe 7y ago
> the next generation (350 kW chargers) It's not even "next generation" chargers; it's next generation EVs at this point. Nearly all new Electrify America rapid charging locations have at least one station that can do 350kW. We're just waiting for EVs like the Taycan* to be released (less than 1 month -- Sept 4th!) to be able to accept charge rates approaching that. EA is on-track to get 2,000 fast chargers at nearly 500 locations up and running by end-of-2019. *The first generation Taycan will charge at 250kW. But the infrastructure is coming online now as EV manufacturers iterate on battery pack technology to accept faster charge rates.