Charging an Electric Vehicle at Home

I recently purchased a 2015 BMW i3 REx for a steal of a price to replace my aging 2002 Volkswagen Jetta TDI. The Jetta still has at least 170,000 miles of life in the engine after the short 230,000 miles it has on the odometer now. At the peak, I was able to average about 55 MPG on a full tank, but now I don’t drive enough to really gain the benefits of a diesel auto’s fuel economy (highway range). I will not get too far into the details of the i3, but a used i3 is a good value with 2014-2015 models in the $18,000-$24,000 price range, and the drivetrain has an 8 years warranty.

I have had it for about a week and a half and was limited to standard level 1 charging, which uses a normal 110V plug in the US. For instance, today, we drained it down to 0 miles of electric range and drove off of the Range Extender (REx). I plugged it in when I arrived home at around 2PM and it indicated that it would complete fully charging at nearly 9AM tomorrow.

A couple of days ago, I ordered a level 2 charger and it was waiting for me when I arrived home. The level 2 charger uses a 220V circuit, similar to an electric clothes dryer or electric oven. I had my garage pre-wired with a 60A circuit when we had the house built in anticipation of getting an electric car.

Here is the parts list of what I have acquired (no affiliate links):

  1. JuiceBox Pro 40 with JuiceNet – $579.00 on Amazon with free Prime shipping
  2. Heavy Duty Garage Storage Wall Mount J Hook 6” – $9.99 on Amazon with free Prime shipping (I just ordered this and don’t have it yet)
  3. Leviton 279 50 Amp NEMA 14-50R Receptable – $10.45 on Amazon with free Prime shipping (I bought this from The Home Depot for about $8 so I could pre-wire before the charger arrived)
  4. Leviton 83026 2-Gang Flush Mount Wallplate – $7.47 on Amazon with free Prime shipping (I also bought this at The Home Depot for about $7)

I arrived to the package sitting outside of my garage. Since I had already connected and secured my receptacles to the existing pre-run 220V circuit, I was able to plug in the charger and test it out, monitoring it for about 5 minutes before mounting. Everything worked well. NOTE: Be extra careful with electricity and do not install it without another set of eyes that can call for emergency assistance. If you are at all apprehensive about it, contact someone that is familiar, up to and including a professional electrician.

I was able to temporarily mount it in about 3 minutes, but I am going to permanently mounted it when I have some extra support in place.

This model comes with WiFi connectivity and can be monitored through an iOS and Android app, and works with Alexa (I haven’t setup the Alexa skill for it, yet). You can control the maximum amperage. The device uses 40A out of the box, but the i3 uses 32A, so I configured it down. It is always a good idea to over buy on capacity and set it lower. So, the circuit is a 60A circuit, the device only pulls 40A, but I have it stepped down to 32A. This gives plenty of clearance and isn’t pushing the limits by any stretch.

I was able to add about 30 miles of range in about an hour. The unit consumes 10kWh, which would translate into about $1/hour for me, but I also have the unit stepped down by 20%, so maybe a rough estimate of $0.80/hour is safe.

Some electric providers offer off-peak pricing for EVs if you charge at night. My provider does not offer this for EVs, but they do offer something called RTOU (Residential Time of Use), which is demand-based pricing for residential customers. Essentially, I get a 10% discount for off-peak electrical consumption, but then peak consumption is 3x the price. I am investigating getting a Tesla PowerWall (maybe I will transfer my Tesla Model 3 deposit over to a PowerWall), which would allow me to switch to RTOU and use the PowerWall during peak times. Peak times for a couple of hours in the mornings and evenings during the Summer months and a couple of hours in the evenings during the Winter months; all other times are off-peak. The great advantage of the PowerWall is that it is like getting a whole house generator in that you can withstand certain power outages, but unlike a generator, you can benefit from it all of the time with demand-based consumption or even day/night with solar or wind generation. With a generator, you only get value if and when you have a power outage.

What I have particularly enjoyed is learning more about electric vehicles, finding charging locations (I have used three different charging networks, so far (ChargePoint at the BMW dealership for free and the mall for a fee, Blink at Ikea for a fee, and EVGo at another mall for free).

Now the standard plug will stay in the small “frunk” to be used whenever I am out somewhere and have the opportunity to charge.

I am also investigating an adapter to allow it to be charged at a Tesla Supercharger as there is one a few miles from home and would increase the locations that I could charge on the road.

UPDATE: The adapter does not work with a Tesla Supercharger.  However, there is an adapter to use with the Tesla High Powered Wall Charger, or Destination charger.  Basically, it is the Tesla home charger.  Some hotels have these so the adapter would be useful for expanding the available chargers.


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