An electric car made by a Chinese auto manufacturer may sell for just $10,000, CNN reported. The small vehicle will retail for $17,500, with a federal tax credit of $7,500, bringing the price down to a very affordable range. Electric cars are popular for their energy efficiency.
According to CNN, Chinese automobile manufacturer Kandi will soon be making a noticeable splash in the American auto market. “Kandi is entering the US market with two small electric cars, one of which—the K27—it plans to sell for just $10,000 after federal tax incentives, but you will have to act fast to get that ultra-low price,” the article said.
“For the first 1,000 buyers the initial purchase price of the little car is expected to be $17,500, which qualifies most people for a $7,500 tax credit. The price for those who buy later will be $19,800, or $12,400 after the tax credit.”
Unfortunately, the K27 is mostly intended for short trips, driving just 100 miles on a single charge. A larger model, the K23, will cost $20,000 after the tax incentive and get 188 miles per charge. Generally, electric cars are popular for their energy efficiency.
It Just Keeps Going, and Going, and Going…
One way to look at energy efficiency is how much energy in joules is required to transport an average passenger a distance of one meter. This is a simpler way to measure efficiency than fuel, since hybrid and electric cars don’t rely solely on gasoline.
“A typical car getting 25 miles per gallon needs 3,000 joules per meter, but that becomes 750 with four passengers,” said Dr. Michael E. Wysession, Professor of Earth and Planetary Sciences at Washington University in St. Louis. “An electric car can require as low as 500 joules per meter, or a little more than 100 joules per meter with four passengers. Yes, this is four to six times more efficient than gas-powered cars.”
For comparison, Dr. Wysession said that a 747 jet consumes about 1,500 joules per meter per person. A hovercraft uses 2,500 while an ocean liner uses 3,400. Things ramp up with a helicopter or a Lear jet, each of which consume 5,400 joules per meter per person. Surprisingly, a jet ski uses a whopping 18,000 joules per person per meter.
Consider Your Sources
“In examining the energy efficiency of an electric car, you have to take into account not just the efficiency of the batteries, but the original source of the energy as well,” Dr. Wysession said. “If it’s coal or nuclear supplying the electricity, then you have to reduce the total efficiency by about two-thirds because coal and nuclear are only about 35% efficient.”
However, he said, if electricity is the original source of energy for your car’s electricity, that “grid-to-motor” efficiency comes up to about 75%. The reason it’s not higher is because several components of the transfer—including the motor, drivetrain, inverter, the battery itself, and the charger—are each between 90%–95% efficient. They must be multiplied together to get the final efficiency of power transfer.
So if we account for the source of electricity, do regular cars stack up in performance against electric cars? Dr. Wysession said that power plant efficiency averages about 35% for coal and nuclear and 60% for natural gas combined cycle, while electricity efficiency is about 93%. Those, combined the 75% efficiency of the car itself, result in a range of 24%–42%.
“On the other hand, a conventional car gets an efficiency of about 15% of the energy of gasoline for the actual running of the car,” he said. “So, even in the worst case, electric cars are still much more energy efficient than conventional cars.”
Dr. Michael E. Wysession contributed to this article. Dr. Wysession is the Professor of Earth and Planetary Sciences at Washington University in St. Louis. Professor Wysession earned his Sc.B. in Geophysics from Brown University and his PhD from Northwestern University.