The ambitious electric vehicle development plan released recently triggered concern on the stability of the Chinese grid system, yet government officials said the smart grid will stand the impact by the time EVs are prevalent in China.

"So long as the grid is smart enough, it can stand the fluctuation caused by simultaneous recharge of numerous EVs," said Jiang Kejun, director of the energy research institute of National Development and Reform Commission.

According to the government development plan, the number of electric cars will reach 30 to 40 million by 2030. Yang Junqian, chief expert of smart grid, EV and renewable energy department of Schneider Electric China, said the pressure on the grid system can be huge, when hundreds of thousands of EVs charge at the same time.

"Turning on the 2 kw air-conditioners at the same time can cause an instant power shortage in summer night in major cities, not to mention charging millions of 20 kw EV batteries in a parking lot," Yang said.

Since few Chinese households have private garage where their EVs can be recharged, most EV owners will have to rely on public recharging facilities such as the recharging pillar near their work place.

However, Jiang said by then the smart grid, which is being developed by the State Grid in China, will come out with strategies to stand the sudden turbulence.

"By storing the power during the off-peak hours, the grid will be able to satisfy the charging needs," Jiang said, "For example, when people drive to their office, park their cars, and plug them into the recharging pillar, the pillar can transport power stored during the night to meet the demand."

"Besides, by 2030, the power generated should reach nine trillion kwh; then the demand from charging electric cars is just a small portion of the available power," he added.

"And with the increase of the electric car battery, the power consumed by EVs will drop significantly. Now an EV needs 15 to 23 kwh a day, but in the near future it can drop to eight kwh."