BMW Car Control Clinic in an ActiveE

Last weekend I had the opportunity to take my BMW ActiveE to a Car Control Clinic run by the BMW Car Club of America, Golden Gate Chapter. I know the car can handle pretty well, so I was very much looking forward to driving it closer to its limit. However, since the clinic took place over 30 miles from my house, I wasn't sure how much battery charge I would use first getting there and then participating in a full-day clinic of hard driving. Luckily, there are hundreds of free EV charging stations along the route between my house and Candlestick Park where the event took place, so I decided to head up early and get a top up charge at a free parking garage in South San Francisco. After the top-up I arrived with over a 90% charge and throughout the day used less than half my charge. If I participate in a followup performance driving clinic I'll feel more confident in skipping the morning top-up.

As for the event itself we rotated between three stations participating in:

• A skid pad to test under and oversteer and the limits of adhesion in the ActiveE.
• A high-speed braking and accident avoidance exercise to get experience with full anti-lock braking stops
• A minor autocross cone course.

I've done all of these activities before in other BMW cars at the BMW Performance Driving Center in South Carolina, so I was most interested in those exercises that highlighted performance of the electric car. The most surprising thing initially was how well this relatively heavy car comes to a complete stop at speed with full anti-lock braking. Perhaps less surprising is the fact that with instant torque, 50/50 weight distribution, and solid handling the ActiveE is great on autocross courses.

Don Louv reports in the April 2013 issue of Roundel magazine that the ActiveE doesn't let you turn traction-control all the way off so he's been unable to get it drifting sideways. On the skid pad, I had the same feeling after turning the stability control off that it was still fighting my oversteer with a bit of understeer. I could certainly get it sliding for short periods of time but it was still fighting me. The skid pad was dry however, and I didn't adjust my tire pressures, so I'd like another go at it in wet conditions to keep the car sideways longer.

7 Months of Mostly Free EV Charging

It has been 7 months already and we've put over 5,850 miles on our electric car. During that time we've charged 196 times at 11 different charging stations, and never once paid for gas or waited for the tank to fill. One of the great things about electric vehicle charging stations, particularly those from ChargePoint is how they are networked and provide an online dashboard where you can view personal charging history and energy consumption. Our home charging station has a built in cellular uplink and is connected to an online account so all charges from home are automatically visible on the website. At public charging stations I scan an RFID card on my keyring to associate the charge with my account.

Using this website, I see that of those 5,850 miles, I used over 2,114 kWh of electricity. 27% of that electricity was consumed overnight by our home charging station in our garage, and the other 73% was provided free by the charging stations at my employer or the free charging stations at San Francisco city parking garages.

In our first month of owning the car, we didn't even have a home charger, and so we were charging exclusively for free, but not really putting that many miles on the car each day. Now that my wife is commuting further to work each day, we put over 50 miles a day and charge it up at home each night and at a parking garage in San Francisco each day while she is at work.

If we assume an electricity price of $0.12 per kWh, then it cost 2,114 * 27% * $0.12 = $68.49 in electricity to drive those 5,850 miles. Gas is approximately $5/gallon in Silicon Valley right now, so $68.49 would buy less than 14 gallons of gas (1 tank!). I'd have to get 418 miles per gallon to come out ahead with a gas car given how much of my driving is subsidized by free electric vehicle charging stations.