SEOUL—South Korea is experimenting with electric buses that can charge wirelessly while in motion, a technology that could help ease the pollution plaguing cities.The city of Gumi, about 150 miles southeast of Seoul, is the testing ground for two so-called on-line electric vehicles, which ply a 15-mile route up to 10 times a day. The locally made buses can charge while moving or when stationed without physical contact with the power supply, a technology on which companies such as QualcommInc. QCOM -0.78% and Bombardier Inc. BBD.B.T +0.85% also are working. At the heart of the buses is power-transfer technology that can shape electromagnetic fields in a specific direction, minimizing lost energy while in transit.
South Korea developed what they say is the most advanced electric vehicle option in the world, a wireless charging system that charges as the bus moves along the road. The WSJ's Jeyup S. Kwaak shows us how it's gaining traction.
The experiment is part of the South Korean government's effort to reduce 30% of the country's greenhouse-gas emissions by 2020. The government also has funded the development of hydrogen-powered engines and electric vehicles that can replace batteries at charging stations automatically.
Dongwon OLEV Corp., a unit of Korea-based Dongwon Group, owns the commercial rights for the power-transfer system. Rides are free during the test run.
The technology makes particular sense for Asia. The rise of cities with 10 million people or more is expected to be pronounced in the region, according to a 2011 United Nations study. It forecast that Asia's urban population would leap to 3.3 billion by 2050 from 1.9 billion.
China also sees zero-emission mass transit as a way to combat air pollution. BYDCo. 002594.SZ -4.25% has delivered hundreds of conventional charge-by-plug electric buses around the country in recent years. The auto and battery maker has reached deals with Singapore and Hong Kong as well as cities in the U.S., Israel, Europe and South America as partners for tests or commercial service.
The in-motion technology's widespread adoption faces significant hurdles, however.
For one, it is expensive. Gumi's system cost 4.8 billion won ($4.3 million), according to the Korea Advanced Institute of Science and Technology, which developed the bus. That includes two carbon-fiber buses at 650 million won each, plus fees for power-supply installation, testing and other costs.
The heavy capital investment needed for infrastructure is another potential roadblock. The project's engineers say costs will drop over time as parts for power transfer go into mass production and they project a 14-year period for the return on investment.
"It will be very expensive and probably not economically practical for the vast majority of urban public transit," says John G. Kassakian, professor of electrical engineering at the Massachusetts Institute of Technology.
Dongwon OLEV says its bus is a step forward, as intermittent charging en route can reduce battery size and bus weight, increasing fuel efficiency. And dispensing with manually controlled charging stations means zero electrocution risk, the project's engineers say.
Dongwon OLEV says it has a joint venture in the U.S. and a subsidiary in Australia but that no deals have been made.
"OLEV promises big reductions in vehicle emissions, but I am concerned that the huge investments required to implement such technologies could be better used to finance lower cost options that may provide similar environmental benefits," says Tim Welch, an assistant professor at the Georgia Institute of Technology. Higher gas taxes and parking fees would lead to fuller buses and increased transit efficiency at lower cost than technological advances, he says.
The Dongwon OLEV system was tested on short routes around South Korea, starting with a 1.4-mile route around a Seoul amusement park in 2010. A 2.4-mile route around the Korea Advanced Institute of Science and Technology campus has been in service for nearly two years. An international exposition in Yeosu, South Korea, used the buses last year.
The technology has proved highly reliable in its test runs, the institute says.
A common concern with wireless technology is its impact on health, especially for people using pacemakers or hearing aids. Institute engineers say the radiation from the bus's power transfer is less than that from a laptop computer. Interference with health devices was addressed by using different frequencies, says Yoon Uoo-yeol, a research professor at the institute's Wireless Power Transfer Technology Research Center.
Engineers are testing a higher-power system to run trams and high-speed trains, which would eliminate overhead electric wires.
