We picked up a used battery EV last year to replace one of our vehicles that was coming off lease, and since then we have been learning about good options for charging, both at home and in public places.
At Home
The first challenge we had was charging the car at home. Our vehicle, a 2014 Mercedes B Class, came with a 110V charger, but that was very slow and was recommended to be plugged into its own electrical circuit (the only one in our garage was already being used by a refrigerator, and therefore not really suitable for long term sharing).
Given that meant we needed a new circuit in the garage for the charger, the obvious thing to install was a higher current EVSE. Our electrician, Kevin from Sun’s Free Solar ,recommended an eMotorWerks JuiceBox Pro 40, which is capable of delivering around 10KW. In our case though we have it limited to just under 7KW because we had existing 240V wiring between our consumer unit and garage wall for an air conditioner unit that we do not have, but that wiring was only rated for 40A (continuous 32A), and not the 50A (continuous 40A) that is needed for 10KW charging. It makes very little difference for our purposes though, and we charge the car once or twice per week, overnight and it is usually done 2-3 hours after it starts.
Utility Discount
Our utility, the city owned Alameda Municipal Power, offers a monthly discount on our electricity bill. The exact amount is based on the gross vehicle weight, and is conditional on only charging the vehicle overnight. Given that we do not currently have a solar system here, and the car is actually not here during the day most days of the week, that limitation was not a problem. The JuiceBox Pro made it simple to ensure we were compliant too. As well as being able to manage the charge rate (locking to the 32A limit of our circuit), the app also allows specification of the allowed charging times. This could also be useful if your utility offers cheaper rate electricity at certain times of day.
When we come home now and want to charge the car, we simply plug it in, make sure the LED indicating the connection is lit and leave it. At 8pm (the start time of our charge window), I receive a message on my phone telling me charging has started. When it completes, another message is sent out telling me it is finished and reporting the amount of charge added to the battery.
The app and the website both allow access to detailed information about each charging session. For example, here is the report for January to date:
Public Charging
When we first picked up the car, the dealer had not managed to charge it. In fact, even today I am not certain the have a fast charger on their premises. Given that the battery was getting very low by the time we drove home, and our lack of high speed charging at home at that point, one of the first things we needed to work out was where we could get a high speed charge locally. Since then, we have also been on the lookout for other charging options that might allow us to extend the range a little. In general though, our experiences with the availability of the chargers has meant that we only use the EV when we can make it both there and back on a single charge.
Here in Alameda there are several places with chargers. There are three free locations on the island I know of:
- two ports from Volta Charging in a mall parking lot
- four ports in the city’s own parking garage downtown
- three at a local business that are not widely known about, and I have not seen on any maps
The free ones, at least at the first two locations listed there, are almost always in use, though we have been lucky a few times and been able to get a free charge.
There are some paid locations too, with prices varying wildly from a very reasonable $0.50/hour (though actually it bills based on KWh, charging around 12.8¢ per KWh) to one that wants $5/hour irrespective of charge delivered (essentially they are charging for the space).
In other locations, we have found that free locations, especially the ones from Volta (which tend to be reasonably fast, and reliable), are usually occupied most of the time. To get one of those requires some patience, and a bit of luck. The paid ones are more likely to be available. We have been successful at getting at least some charge from locations in Walnut Creek, Dublin/Pleasanton, but never in San Francisco where the demand for the limited number of spaces is even higher.
Valet Options
At the end of 2017, Chargepoint announced a product specifically targeting valet and fleet managers who need to charge multiple EVs in a lot, allowing them to monitor the charge levels of the vehicles they are watching, and move them off a charger once they are done.
Our favorite airport parking, Expresso Parking, offers discount rate indoor valet parking with a free charge at their “juice bar” for people parking EVs with them too. They make sure you’re charged before you return, and can move cars in & out of charging bays to maximize utilization.
Given the issues with availability of the chargers at the malls around here, and the obvious expense of adding more chargers, I suspect some of the higher end malls that already offer valet parking services will add EV charging to that service. In New York, the Luxe Valet service has partnered with Tesla to provide their valet parking service with an option charge (not free).
Office Parking
The final place that may be available for charging your EV, and one that makes a lot of sense given how much time many EVs spend there, is in the offie parking lot. Unfortunately for us, my office has no parking (I work in downtown San Francisco, and commute by ferry or bus anyway) and while my wife’s office has plenty of parking, as of yet they do not have any EV charging posts. They do let people plug into a 110V outlet in the shipping dock if somebody is in desperate need of a charge to get home, and they are meant to be trying to get permits to add fast EV charging posts.
Some offices complexes do have EV charging points in their parking lots. As with malls though, unless there is a scheme to have cars move off once charged, these are likely to be occupied all day by the first people to arrive.
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