GreenBkk Auto | 2011 Technology of the Year: Electric Propulsion

2011 Technology of the Year: Electric Propulsion

Credit: Automobile Magazine (http://www.automobilemag.com)

The skeptics insisted it would never happen, that electric cars couldn't compete with internal combustion a century ago, and -- until cheap, powerful, and dependable batteries arrive -- they never will.

At Automobile Magazine, we beg to differ. Three electrically driven cars from major manufacturers are on the U.S. market today, and others are on the show circuit or under development for future introduction. In other words, the barrier blocking this alternative to internal combustion has been lifted. While mainstream traffic will continue cruising straight ahead, a new exit ramp is open for those who are anxious to experience the latest powertrain engineering advancements. Electric propulsion is Automobile Magazine's 2011 Technology of the Year.

You should have seen this coming. We celebrated hybrids as our Tech of the Year in 2000 and 2008. Last year, lithium-ion batteries earned the prize. Five manufacturers are now building factories in the United States to supply the budding electric-car industry with advanced batteries. General Motors and Nissan have invested billions to engineer, produce, and market the Chevy Volt and the Nissan Leaf to the first wave of mass-market electric-car customers.

Although the arrival of suitable batteries and huge capital commitments are the electric car's great enablers, the driving force behind them is a burning need for more efficient transportation. Engineers have achieved major fuel economy increases attributable to lighter materials, aerodynamic bodies, and vastly improved powertrains, but those gains are incremental compared with the efficiency strides that are possible with electric propulsion.

Following our best caveman instincts, we've built our personal transportation system around fire-the shrewdly controlled combustion of fossil fuels within piston (and a few rotary) engines. Unfortunately, the most efficient gasoline engines have an energy-conversion efficiency of only 35 percent. Pour a gallon of gas in your tank, and only about one-third of the energy contained in that fuel reaches the transmission to drive the wheels. Another third goes out the exhaust pipe as waste heat, and the remaining third is dumped to the cooling system or radiated to the atmosphere. Diesels also waste their share of energy, although their conversion efficiency is moderately higher, at about 43 percent.

The better way is electricity. AC motors commonly operate at 90 percent energy-conversion efficiency. They produce and waste minimal heat. Furthermore, energy that comes from an outlet instead of a pump is generally cleaner and cheaper. Charging the batteries for a forty-mile drive in the Volt or eighty miles in a Leaf costs only a few pennies per mile. Every kilowatt-hour of propulsion energy drawn from a plug diminishes both tailpipe emissions and the amount of oil we must import. After decades of faithful service in our trains, elevators, refrigerators, and power tools, electric motors are ready to hum under the hoods of our cars.

This is not to suggest that Ferrari's screaming eight- and twelve-cylinder engines are obsolete. Nor that hybrid vehicles, which marry hot and cold energy-conversion devices, are passé. But we are convinced that electric propulsion is ready to finally assume a significant role as one of several powertrain options for the future.

We're not alone in that opinion. A recent study by Credit Suisse, a financial services company, forecasts a global fleet of five million electric cars by 2020. As electrics roll out this year, we expect early-adopter enthusiasm to finally muzzle the skeptics.

Credit: Automobile Magazine (http://www.automobilemag.com)