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My god, not having enough on site fast chargers for both charging the fleet and reassuring renters that if nothing else they can come back to the airport and to

My god, not having enough on site fast chargers for both charging the fleet and reassuring renters that if nothing else they can come back to the airport and top up is really stupid

sandworm101 3y ago
>> My god, not having enough on site fast chargers for both charging the fleet and reassuring renters Take a look at a major airport. They could average a hundred rental cars arriving, with peaks into the hundreds. Even assuming every can arrives at a half-charge, the power requirements would be immense. At 50kwH per car, charging up 100 cars every hour would require, at an absolute minimum, a 5000kw/5mW connection.
- fnbr 3y ago
  That's a great reason not to have electric rental cars, but not a great reason to not charge rental cars.
- yummypaint 3y ago
  Airports are massive pre-planned industrial facilities with utility connections to match. Getting chargers there should be easy mode compared to most businesses.
  - mulmen 3y ago
    They also don’t offer automotive refueling services at the airport. This is the same reason they charge a premium to fill the tank. The constraints are the same for ICE and EV in this case.
    - smeej 3y ago
      What's your source for this? I'm just realizing I might be way off-base, but I thought airport car rental places all had their own fueling stations, and just overcharged you because they can and there's nothing you can do about it, and I'd thought of it as one of those "everybody knows" kinds of things. So now I'm very surprised to hear otherwise.
      - mulmen 3y ago
        I don’t have a source. It just seems obvious to me they wouldn’t bother with the cost of maintaining that infrastructure. Do you have any reason to believe car rental companies maintain onsite fuel stations? Have you ever seen one? Why don’t they let customers use it? There are already gas stations near airports. If a car needs gas they pay someone to drive it there and fill it up. That’s the source of your inflated prices.
        smeej 3y ago
        I haven't at an airport, but I have at freestanding ones. Having fuel delivered to a tank with a pump isn't really that involved as infrastructure goes. You're just buying the fuel wholesale instead of retail. You don't need the same size underground tank as a gas station, but you can hold more than enough to fill up whatever you need to from a fleet of cars. As for why they don't let customers use it? This is obvious. They'd rather overcharge you. And they know nobody's going to do something dumb at the pump if it's only their own team doing it. Plus, often when I rent a car, it isn't full. I'm sure they still charge the person "to fill the tank," but they don't actually fill it, so the total they'd have to store on-site is even less than if they were actually filling the cars. I also assumed they had somewhere to store siphoned fuel, because every car I've ever driven has at least a gallon before the needle moves off of "F," but rental cars drop below F immediately. I've always assumed they were siphoning out a gallon or more any time someone did return the car all the way full.
  - smallnamespace 3y ago
    > pre-planned The power requirements were not drawn up with the car rental agency in mind. Maybe you can get the airport to cooperate and ask the utility to expand capacity - how many years of planning do you think that takes?
    - wlesieutre 3y ago
      Yes, definitely a project, especially with the shortages of transformers lately. But even if it delayed their (attempted) EV shift, it’s something Hertz needed to have done before buying a bunch of EVs. Handing out discharged EVs to customers who haven’t driven an EV before was a totally braindead move. They have the added challenge of people dropping off cars at a different place from where they started, so they can’t necessarily say “we’re going to start with EVs at our new facilities where we can design that capacity from the start.” They needed fast charging everywhere for this to go smoothly.
    - monknomo 3y ago
      Sounds like something a car rental agency that wants to have a bunch of electric rentals should probably think through before yeeting a fleet into existence....
  - qsi 3y ago
    Yes, but many are also very old and don't necessarily have large power lines leading to the car park as it's never been necessary in the past. Newark was mentioned as a case in point, where power is simply not available at the scale they'd need it. Of course, Hertz should have thought of that...
- cduzz 3y ago
  50kwH is a huge charger. You wouldn't need many of such feeds even with hundreds of cars. How long do cars sit in the lot? Do you need to send cars out at 100% full? Is it good enough to make sure the cars leave the lot with 50-80% full? They're returned, inspected, cleaned, put in the "outgoing" queue. I suspect having DCFC for just the cleaning area and then 16 or 20 or 24a /240v posts for L2 charging the cars as they sit waiting to be rented would more than suffice. Other big issues would be around having to have dedicated parking for EVs and also having charging posts sticking out of the ground all over.
  - masklinn 3y ago
    > 50kwH is a huge charger. 50kWh is not the charger, half the battery capacity for the cars (as decided by GP). And 50kW would not be a huge charger, or even a large one, it's the bottom end of DC charging. > I suspect having DCFC for just the cleaning area and then 16 or 20 or 24a /240v posts for L2 charging the cars as they sit waiting to be rented would more than suffice. Aside from not being very efficient, 24@240 is not really a thing that's used. 32@240 is relatively standard but it's 7.2kW and generally considered a residential AC charger, acceptable when 3-phase is not available (or too expensive). It needs 7 hours to half-charge a 100kWh battery.
    - cduzz 3y ago
      I'd suggest that 50kw/h is way too small and way too large. A car rental setup would benefit from having a couple big DCFC setups where cars are inspected / cleaned. EVs charge fast if the battery is empty (and warm) -- so the car comes in, is inspected and cleaned and put on a fast charger, and in 20 minutes will get to ~50% charge (regardless of battery size). As far as "not efficient" or "nobody uses" well, 240 (or 208 if you're in a commercial setup with 2 legs of a 3 phase) is "normal" and a 16a / 20a / 24a AC charger will put reasonable charge on the car while it's just sitting there waiting to be rented again. EV's don't need to be fully charged to be useful so you don't need to put the battery back to 100% before sending it out again. "your car is at 60% charge and has 180 miles of range right now; your car's nav will tell you where to charge if you need more range to get to where you're going. We'll bill for the power if you bring it back to us at less that 60% full. Have a nice day!" I'm not sure what the turnover is for a rental lot -- I suspect "it depends" but I suspect it's not unusual to have cars on the lot for 6-12 hours before they're sent out again. IMO As long as the car has 60% or better charge (or, 150-180 miles of range) it's "good to go". At least for most "airport rental in a major metro area" situation. As far as charging efficiency -- anything charging at 240/208v is "good enough" -- the differences between 16a or 20a or 24a or whatever are minor relative to the bump from 120v to 240v.
- monknomo 3y ago
  This is a problem for a car rental company that wants to provide electric cars to solve, sure. The rental co really needs to provide reasonable charged cars, and so long as charging infrastructure is dicey (especially with hotels in the mix) they could provide peace of mind to their customers by providing a known charging spot. Put it wherever, I'm not Hertz, the airport is not Hertz's customer, but I would have a pretty strong bet that Hertz's customers would expect this sort of thing.
- SilasX 3y ago
  Still scratching my head at why they couldn't make EV batteries hot-swappable, at least with a technician and specialized equipment assumed. (You'd need to changing the finance model a bit, of course, so that the batter replacement service were sold separately from the car -- but this would be easiest for the case of a car rental fleet.)
  - ghaff 3y ago
    It was tried and failed--admittedly a long time ago. However, today, I want to have a pretty good idea of the battery health of the battery in my car and avoid it randomly changing when I "fill up." Also most recharge locations are 24-hour with no one on staff so you'd drastically cut when and how an automated replacement could happen.
    - SilasX 3y ago
      Yes, a user-swappable would be even better, but even limiting it to banker's hours allows you a five minute complete fill-up, which is still 100x than what it actually takes to fully charge via outlet, or even the 15 minutes you would take if you're lucky enough to find an available supercharger, which still only gives you 200 miles.
- _ea1k 3y ago
  Not necessarily unheard of though. Tesla is planning a 52 stall site at O'Hare. That will probably be ~6MW at peak.
- ghaff 3y ago
  Furthermore, at a rental car center, you're not just swinging in and swinging back out. It could change of course but they're setup that once you drive in, you're returning the car. (Re: comments about rental car center being the charger of last resort.) (I had a friend joining me on a trip a number of years back. We wanted to add them to the contract once they arrived. I had to patiently explain that we could do it with a company that also had an off-airport location but we couldn't drop by the car rental center at the airport. I've had other experiences with how car rental companies really don't have good mechanisms to change things once you've signed and initialed the contract.)

My god, not having enough on site fast chargers for both charging the fleet and reassuring renters that if nothing else they can come back to the airport and top up is really stupid

sandworm101 3y ago

>> My god, not having enough on site fast chargers for both charging the fleet and reassuring renters Take a look at a major airport. They could average a hundred rental cars arriving, with peaks into the hundreds. Even assuming every can arrives at a half-charge, the power requirements would be immense. At 50kwH per car, charging up 100 cars every hour would require, at an absolute minimum, a 5000kw/5mW connection.

fnbr 3y ago
That's a great reason not to have electric rental cars, but not a great reason to not charge rental cars.
yummypaint 3y ago
Airports are massive pre-planned industrial facilities with utility connections to match. Getting chargers there should be easy mode compared to most businesses.
- mulmen 3y ago
  They also don’t offer automotive refueling services at the airport. This is the same reason they charge a premium to fill the tank. The constraints are the same for ICE and EV in this case.
  - smeej 3y ago
    What's your source for this? I'm just realizing I might be way off-base, but I thought airport car rental places all had their own fueling stations, and just overcharged you because they can and there's nothing you can do about it, and I'd thought of it as one of those "everybody knows" kinds of things. So now I'm very surprised to hear otherwise.
    - mulmen 3y ago
      I don’t have a source. It just seems obvious to me they wouldn’t bother with the cost of maintaining that infrastructure. Do you have any reason to believe car rental companies maintain onsite fuel stations? Have you ever seen one? Why don’t they let customers use it? There are already gas stations near airports. If a car needs gas they pay someone to drive it there and fill it up. That’s the source of your inflated prices.
      - smeej 3y ago
        I haven't at an airport, but I have at freestanding ones. Having fuel delivered to a tank with a pump isn't really that involved as infrastructure goes. You're just buying the fuel wholesale instead of retail. You don't need the same size underground tank as a gas station, but you can hold more than enough to fill up whatever you need to from a fleet of cars. As for why they don't let customers use it? This is obvious. They'd rather overcharge you. And they know nobody's going to do something dumb at the pump if it's only their own team doing it. Plus, often when I rent a car, it isn't full. I'm sure they still charge the person "to fill the tank," but they don't actually fill it, so the total they'd have to store on-site is even less than if they were actually filling the cars. I also assumed they had somewhere to store siphoned fuel, because every car I've ever driven has at least a gallon before the needle moves off of "F," but rental cars drop below F immediately. I've always assumed they were siphoning out a gallon or more any time someone did return the car all the way full.
- smallnamespace 3y ago
  > pre-planned The power requirements were not drawn up with the car rental agency in mind. Maybe you can get the airport to cooperate and ask the utility to expand capacity - how many years of planning do you think that takes?
  - wlesieutre 3y ago
    Yes, definitely a project, especially with the shortages of transformers lately. But even if it delayed their (attempted) EV shift, it’s something Hertz needed to have done before buying a bunch of EVs. Handing out discharged EVs to customers who haven’t driven an EV before was a totally braindead move. They have the added challenge of people dropping off cars at a different place from where they started, so they can’t necessarily say “we’re going to start with EVs at our new facilities where we can design that capacity from the start.” They needed fast charging everywhere for this to go smoothly.
  - monknomo 3y ago
    Sounds like something a car rental agency that wants to have a bunch of electric rentals should probably think through before yeeting a fleet into existence....
- qsi 3y ago
  Yes, but many are also very old and don't necessarily have large power lines leading to the car park as it's never been necessary in the past. Newark was mentioned as a case in point, where power is simply not available at the scale they'd need it. Of course, Hertz should have thought of that...
cduzz 3y ago
50kwH is a huge charger. You wouldn't need many of such feeds even with hundreds of cars. How long do cars sit in the lot? Do you need to send cars out at 100% full? Is it good enough to make sure the cars leave the lot with 50-80% full? They're returned, inspected, cleaned, put in the "outgoing" queue. I suspect having DCFC for just the cleaning area and then 16 or 20 or 24a /240v posts for L2 charging the cars as they sit waiting to be rented would more than suffice. Other big issues would be around having to have dedicated parking for EVs and also having charging posts sticking out of the ground all over.
- masklinn 3y ago
  > 50kwH is a huge charger. 50kWh is not the charger, half the battery capacity for the cars (as decided by GP). And 50kW would not be a huge charger, or even a large one, it's the bottom end of DC charging. > I suspect having DCFC for just the cleaning area and then 16 or 20 or 24a /240v posts for L2 charging the cars as they sit waiting to be rented would more than suffice. Aside from not being very efficient, 24@240 is not really a thing that's used. 32@240 is relatively standard but it's 7.2kW and generally considered a residential AC charger, acceptable when 3-phase is not available (or too expensive). It needs 7 hours to half-charge a 100kWh battery.
  - cduzz 3y ago
    I'd suggest that 50kw/h is way too small and way too large. A car rental setup would benefit from having a couple big DCFC setups where cars are inspected / cleaned. EVs charge fast if the battery is empty (and warm) -- so the car comes in, is inspected and cleaned and put on a fast charger, and in 20 minutes will get to ~50% charge (regardless of battery size). As far as "not efficient" or "nobody uses" well, 240 (or 208 if you're in a commercial setup with 2 legs of a 3 phase) is "normal" and a 16a / 20a / 24a AC charger will put reasonable charge on the car while it's just sitting there waiting to be rented again. EV's don't need to be fully charged to be useful so you don't need to put the battery back to 100% before sending it out again. "your car is at 60% charge and has 180 miles of range right now; your car's nav will tell you where to charge if you need more range to get to where you're going. We'll bill for the power if you bring it back to us at less that 60% full. Have a nice day!" I'm not sure what the turnover is for a rental lot -- I suspect "it depends" but I suspect it's not unusual to have cars on the lot for 6-12 hours before they're sent out again. IMO As long as the car has 60% or better charge (or, 150-180 miles of range) it's "good to go". At least for most "airport rental in a major metro area" situation. As far as charging efficiency -- anything charging at 240/208v is "good enough" -- the differences between 16a or 20a or 24a or whatever are minor relative to the bump from 120v to 240v.
monknomo 3y ago
This is a problem for a car rental company that wants to provide electric cars to solve, sure. The rental co really needs to provide reasonable charged cars, and so long as charging infrastructure is dicey (especially with hotels in the mix) they could provide peace of mind to their customers by providing a known charging spot. Put it wherever, I'm not Hertz, the airport is not Hertz's customer, but I would have a pretty strong bet that Hertz's customers would expect this sort of thing.
SilasX 3y ago
Still scratching my head at why they couldn't make EV batteries hot-swappable, at least with a technician and specialized equipment assumed. (You'd need to changing the finance model a bit, of course, so that the batter replacement service were sold separately from the car -- but this would be easiest for the case of a car rental fleet.)
- ghaff 3y ago
  It was tried and failed--admittedly a long time ago. However, today, I want to have a pretty good idea of the battery health of the battery in my car and avoid it randomly changing when I "fill up." Also most recharge locations are 24-hour with no one on staff so you'd drastically cut when and how an automated replacement could happen.
  - SilasX 3y ago
    Yes, a user-swappable would be even better, but even limiting it to banker's hours allows you a five minute complete fill-up, which is still 100x than what it actually takes to fully charge via outlet, or even the 15 minutes you would take if you're lucky enough to find an available supercharger, which still only gives you 200 miles.
_ea1k 3y ago
Not necessarily unheard of though. Tesla is planning a 52 stall site at O'Hare. That will probably be ~6MW at peak.
ghaff 3y ago
Furthermore, at a rental car center, you're not just swinging in and swinging back out. It could change of course but they're setup that once you drive in, you're returning the car. (Re: comments about rental car center being the charger of last resort.) (I had a friend joining me on a trip a number of years back. We wanted to add them to the contract once they arrived. I had to patiently explain that we could do it with a company that also had an off-airport location but we couldn't drop by the car rental center at the airport. I've had other experiences with how car rental companies really don't have good mechanisms to change things once you've signed and initialed the contract.)