I confess. I had been holding out a long time before finally making my purchase of an all-electric car. I ordered a shiny new red Nissan Leaf in October 2011 that has, on average, a 120-kilometer (75-mile) range. My first week of owning I insisted on driving it across the San Francisco Bay Area to pick up my daughter at the Oakland, Calif., Airport. Not sure whether it could have made the 130-km round trip, I arranged to arrive a couple of hours early to charge it at a nearby Nissan dealership for the drive back. The trip went smoothly.
Since then my wife and I have also purchased a Tesla Model S that is powered by an 85 kWh battery and has, on average, a 400-kilometer range. With these two cars (which we share, alternating months) we have learned a lot more about owning and operating all-electric cars without the security of gasoline to back us up.
THE EV ADVANTAGE
All-electric cars do come with many advantages. For one, there is no stopping at gas stations. Like my cell phone, I plug in the car when I get home in the evening, and it’s fully charged by the time I leave the next morning. The cars are quiet, which makes for a more pleasant driving experience. There’s not much in the way of maintenance—no oil changes, and brakes are expected to last 160 000 km because of regenerative braking. There’s plenty of storage space in the Tesla with a trunk both in the front and back of the car since the motor is much smaller than a gas engine, and there’s no transmission and radiator. Finally, the Tesla uses large displays and a modern user interface. The over-the-air software distribution makes it easy for the company to upload the latest updates and settings to the vehicle, which is a breath of fresh air for the automotive industry. Did I mention that the Tesla goes from 0 to 96 kph (0 to 60 mph) in just 5.4 seconds?
Like anything else, there are trade-offs. The high purchase price (at about US $90 000) for the Tesla Model S is certainly an issue, although the Leaf could be a money-saver over gas cars. The ability to charge can be complicated, especially for those who do not have a garage or access to home charging stations. The infrastructure to charge while traveling is not fully developed, with charging stations few and far between. Similarly, there is variation in the range of an EV depending on driving style, terrain, and weather. The car uses energy to heat the interior of the car and its battery in cold weather, ultimately reducing range. Moreover, there are several unknowns. This is a new technology, and it’s too early to know how EV batteries will degrade over time or how well the car companies will handle replacing the batteries.
I have no range anxiety when driving our Model S around the Bay Area. I simply go, enjoy the drive, and plug in when I get home at night. However, should I need to drive out of the Bay Area to say California’s Napa Valley (about 92 km round trip), I need to plan my driving to make sure any side trips keep me in range. Longer trips would definitely require making stops at Tesla’s supercharger networks, which can charge the car in half hour, or searching for hotels with overnight chargers. But we’ve made it work. We have taken trips to many destinations including Lake Tahoe, Calif., a 772 km round trip; and Los Angeles, a 1190 km round trip. When we travel a few times a year to our cabin in Nevada’s Sierra region, which is not within range of a supercharger, we use one of our daughter’s gasoline-powered cars.
The Leaf can be more complicated. Although I love it, one needs to plan more often. It is no problem for my typical commute of 40 km round trip to work at Google in Mountain View, Calif. But when my wife or I plan to drive a new local route, we check Google Maps to get a mileage estimate and see if we might need to trade cars that day.
The Tesla Model S in particular shows what all electric cars can be in the near future. It is a no-compromise car that doesn’t cause range anxiety with significant advantages over gas cars. Its main disadvantage, of course, is cost. The Nissan Leaf is great for predictable driving, such as a short commute to work, and can save money for many drivers. But its range limits are easily reached. It can be a great second car option for many families.
This article is excerpted from the IEEE Transportation Electrification Newsletter.
Hy Murveit currently works at Google as part of its self-driving car team. He was a co-founder of Nuance Communications, a speech recognition software company, in which he served as vice president of research and development.