Q I am a happy owner of an all-electric Nissan Leaf. I have had it for two years and it has been extremely reliable. I do have range anxiety, but have managed to cope. But with regard to the cost-effectiveness of electric cars vs. gas-powered cars, there is a lot of confusion.

Steve Klebe

A You have that one right. In a recent column, I wrote that if electricity costs 11-plus cents per kWh and the vehicle consumes 34 kWh to travel 100 miles, the cost per mile is about four cents. By comparison, the cost to operate a medium-sized gas-powered car for gas and oil is around 15 cents a mile.

Some readers said I need to go back to Math 101 and I would discover that there is no cost savings, while others insist the cost of charging an electric car can be even lower. So charge those batteries and let's go.

Q You've got a brownout in your electric-car operating cost math. First, electricity does not cost 11 cents per kWh. On my baseline bill, PG&E gets 13.2 cents. But if I drive a gorgeous Tesla 2,000 miles a month, adding 680 kWh, my rate will rise to 33 cents per kWh for the extra power drain. ... Your arithmetic is off. After using only 120 kWh in a month, you're up in the top rate tier paying 35 cents per kWh. So to charge a 24 kWh battery for your 70-mile-range example electric car would cost $8.40, or about 12 cents per mile driven. ... Are you a shill for Volt and Leaf? ... Check your PG&Bandit bill. The cost to add an electric vehicle to a typical San Jose-area home is about 36 cents per kWh. The cost per mile is in excess of 12 cents, above the cost of gas for my Prius at 9 cents a mile (44 mpg gallon at $4 per gallon).


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John Dannenberg, Gene Shklar, Richard Peekema. Al Spencer, Doug Adams, Gary Johnson and more

A Now to the believers.

Q I think you gave a good summary with your response that a typical electric car uses about 34 kWh to go 100 miles and that a kWh costs about 11 cents. ... Better yet, PG&E has a PEV incentive wherein the cost per kWh after midnight is dropped from 11 cents to 3 cents. That would make the cost per mile about one cent. ... Our trip to San Diego in our new Tesla S had a gas cost per mile of zero, zilch and nada. And free is a very good price. ... Another part of the pricing is that an awful lot of public charging stations are free. Where I work, EV charging is free, so half of my daily commute is free of charge. ... The whole other side of the equation is maintenance. For an EV, the only substantive maintenance items are tires. Most braking is done as regenerative braking, with the pads used only for hard stops. The elephant in the room, however, is replacing the main storage battery. At some point with any electric car, that will need to be done, and may cost thousands of dollars.

Brad Pennington, Nick Sayer and more

A Tesla's Model S battery is under warranty for 125,000 miles or eight years, whichever comes first.

Q I have a Nissan Leaf that I drove 900 miles one month and used 253 kWh. With the time-of-use meter, the cost per kWh at off-peak times was nine cents, or about $23 a month. By contrast, I was spending $130 a month on gas alone.

Ann Friauf

Mountain View

A And ...

Q Your response was accurate, but you should also note that PG&E offers a time-of-day charging rate equivalent to 5 cents per kWh. That rate kicks in when charging during off-peak hours. So the cost per mile reduces to 2 cents per mile for an electric car, compared to 15 cents per mile for a medium-sized car. Anyone can get this PG&E rate. Just call them.

Joe Longo

Saratoga

A And ...

Q The Department of Energy recently introduced the concept of an eGallon. It compares the cost of a gallon of gas vs. the cost of electricity to go the same distance. In California it shows that the average cost of a gallon of gas is $3.98 and an equivalent "gallon" of electricity is $1.51. That's quite a savings.

Joe Huber

Pleasanton

A Go to energy.gov/articles/egallon-how-much-cheaper-it-drive-electricity and check it out.

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