4 ms·

The two issues I see with pure battery solutions are weight and recharge time. As density increases we can solve the weight issue which is a serious negative cu

The two issues I see with pure battery solutions are weight and recharge time. As density increases we can solve the weight issue which is a serious negative currently but the issue with more density/etc is that charging systems may evolve beyond the point of being installed anywhere but dedicated facilitates. Has anyone calculated the maximum in KW/H or such that a normal house hold could sustain from standard street connections?

audunw 10y ago
> Has anyone calculated the maximum in KW/H or such that a normal house hold could sustain from standard street connections? I don't feel like this is very relevant. The number of people who can't charge their daily need within 8 hours on a 10kW connection is on the order of one in every 10'000, if not less. Or maybe you assume people charges at home in the same pattern as how they fill gasoline? I.e., they only charge when the battery is down to like 30%? That's probably not gonna be the case. If you have the option to charge at home, there's no reason not to plug it in every night. A significant number of people will need to drive long distance 2 or more days in a row, every once in a while, so that has to be solved by rapid charging stations. We will end up with ~350kW rapid chargers (the rough physical limit with water cooled cables), which is almost fast enough that it'd feel like filling gasoline does. But yeah, that will be dedicated facilities with grid storage scale batteries to smooth power consumption.
- vvanders 10y ago
  Yup in ~2 years of EV ownership only time I've every wanted faster charging at home(~15kW) was once after ~7 hours of driving with 5% left when I finally got home. Just ended up taking the other car we had, if I needed to I could have just hung out at the supercharger for another 15 minutes.
- pbhjpbhj 10y ago
  What's the charging limit on the car end of the cables limit it to 350kW. If it's a purpose built charge-station then why not superconducting cabling, or pumped liquid nitrogen, or ... that would push to the limit of the car/battery.
maxerickson 10y ago
In the US the 'standard' service for new household installations is 100 amps, but there isn't anything unusual about 200 amp service. So with the larger panel, a bit more than 40 kW. And maybe 15 kW with the smaller panel if you want to be able to run other stuff. So 6.5 hours is enough to fully charge the biggest Tesla packs using a normal connection. Install a bigger service and you can do 200 kW in that time (I guess charging might slow down, but that's the facile napkin math). It's also likely to be acceptable to only add 500 miles of range in the first night of charging.

audunw 10y ago

> Has anyone calculated the maximum in KW/H or such that a normal house hold could sustain from standard street connections? I don't feel like this is very relevant. The number of people who can't charge their daily need within 8 hours on a 10kW connection is on the order of one in every 10'000, if not less. Or maybe you assume people charges at home in the same pattern as how they fill gasoline? I.e., they only charge when the battery is down to like 30%? That's probably not gonna be the case. If you have the option to charge at home, there's no reason not to plug it in every night. A significant number of people will need to drive long distance 2 or more days in a row, every once in a while, so that has to be solved by rapid charging stations. We will end up with ~350kW rapid chargers (the rough physical limit with water cooled cables), which is almost fast enough that it'd feel like filling gasoline does. But yeah, that will be dedicated facilities with grid storage scale batteries to smooth power consumption.

vvanders 10y ago
Yup in ~2 years of EV ownership only time I've every wanted faster charging at home(~15kW) was once after ~7 hours of driving with 5% left when I finally got home. Just ended up taking the other car we had, if I needed to I could have just hung out at the supercharger for another 15 minutes.
pbhjpbhj 10y ago
What's the charging limit on the car end of the cables limit it to 350kW. If it's a purpose built charge-station then why not superconducting cabling, or pumped liquid nitrogen, or ... that would push to the limit of the car/battery.

maxerickson 10y ago

In the US the 'standard' service for new household installations is 100 amps, but there isn't anything unusual about 200 amp service. So with the larger panel, a bit more than 40 kW. And maybe 15 kW with the smaller panel if you want to be able to run other stuff. So 6.5 hours is enough to fully charge the biggest Tesla packs using a normal connection. Install a bigger service and you can do 200 kW in that time (I guess charging might slow down, but that's the facile napkin math). It's also likely to be acceptable to only add 500 miles of range in the first night of charging.