The airport charging solution

by Ernie Hernandez on September 27, 2011

Eaton quick chargerAn idea for more productive airport EV charging

Some airports (LAX, San Francisco and Denver – that we’re aware of so far) are offering either free parking, free charge stations or both to electric vehicle (EV) owners. The challenge to the current solution is two-fold:

  • What do you do if you show up and there are no charge stations available?
  • If you have a several day trip, is it fair to block a charge station while gone on your extended trip while others may only have overnight trips to make?

These airports typically offer several Level 2 240 volt charge stations with 120 volt outlets to use the vehicle trickle charge equipment. San Francisco airport looks like they offer a total of 20 charge stations. Most airports make these stations available on a first come, first serve basis. Which is fine if you happen to arrive first. But even then, maybe not. We have already read about LEAFs being unplugged shortly after being plugged in by later arrivals that were still there when the first LEAF owner returned. While seeming like a good idea, the unknown trip duration and arrival and departure times of other travelers thrown into this system provides many opportunities for the system to fail. Also, if more EVs are in need of the system than there are charge stations available, someone will inevitably be the odd man out.

We propose an alternative system. One that can accommodate a larger number of vehicles, and one in which no EV owner will not get their needed electric fix. It is simply this – rather than install a large number of 240 volt Level 2 charge stations in the parking area, create an EV charging area separate from the parking facilities. Picture the cell phone lots that you currently see prior to many arrival terminals. These EV charging areas will be equipped with two (or more) DC quick charge stations and located near the parking facility exits. Rather than charging your car when you arrive, you charge upon your return. We really don’t imagine that most drivers will arrive at the airport with a battery state of charge of less than 10%, although some may. No matter. A maximum wait time of 30 minutes to get an 80% charge from empty, with a more likely charge time of 10 to 20 minutes for most. When Nissan brings their 240 volt DC quick charger to the US with its price tag of under $10,000 per unit, it will be possible to install several stations thereby almost insuring no wait for an available unit, and an 80% charge to get you home.

This system will require some vigilance on the part of the airport though. Signs need to be in place notifying users that cars will be towed after 30 minutes to discourage travelers from parking at the DC quick charge and flying off to their destination. Cars left unattended should be towed as they defeat the whole purpose of the quick charge idea.

The implementation of a system such as this will ensure that any electric vehicle owner will be able to get their needed charge for the return trip home. Granted there may be a short wait for an available station, but in our view the current system has several significant obstacles to overcome. This proposed system will only delay your return home by a short time, and will guarantee that a charge will always be available. We think that it is a reasonable alternative.

Update: See our follow-up article to this discussion here.

{ 4 comments… read them below or add one }

Tom K September 28, 2011 at 8:53 am

I think there should be multiple 120v outlets placed all over the airport parking to allow for trickle charging while you are on a long trip, in addition to a handful of quick chargers…


Ernie Hernandez (LEAFguy) September 28, 2011 at 1:26 pm

I agree. I had that same thought after I posted this. If you will be gone for over 20 hours, all you need is the 120 volt access.


Kevin July 13, 2015 at 4:28 pm

Excellent idea. I’ve thought about this myself after dropping family off at SFO, needing to charge and having to wait a long time at the airport to charge my EV because there are only level 2 charges. You’d think that ChargePoint and SFO would have thought it through a bit more before installing ONLY level 2 chargers.


Ernie Hernandez July 13, 2015 at 8:54 pm

Kevin – Welcome to Living LEAF. Sometimes the planning committees need to get input from the end user to see how things might work best. Unfortunately, that’s not always the case.


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