China is the world's largest market for electric vehicles. According to the International Energy Agency, China accounted for over 40 percent of EV sales worldwide in 2016. Chinese EV companies are going beyond borders. One company, BYD Auto, has helped London develop the world's first zero emission double-decker electric bus.

ISBRAND HO, MANAGING DIRECTOR BYD EUROPE "The most important parts of an electric bus are the three components, the battery, the electric drivetrain, and something we call BMS -- the battery management system. All these three components are still manufactured, very proudly, in China at this point."

Electric buses have brought clean energy and quietness to the city. However, of the roughly 9,500 buses in London, only 73 of them are electric. Ho says electric vehicles are the solution. But compared with traditional vehicles and hybrid vehicles, EV might be a bit expensive for the consumer.

ISBRAND HO, MANAGING DIRECTOR BYD EUROPE "The electrical cars, automotive that is used by consumers today, they are more expensive today because of two reasons. The economy of scale, that's the most important reason. The second thing is there are a lot of local structure build-ups that need to be implemented."

Indeed, electric vehicles are still a niche market. Even for China, only one percent of the roughly 28 million cars sold in 2016 was electric. Government research has pointed out that a lack of supplementary facilities has been a key barrier to EV development. China's Minister of Science and Technology says China is following the global trend to go from fuel-powered vehicles to electric ones.

WAN GANG MINISTER OF SCIENCE & TECHNOLOGY "We are developing electric vehicles to optimize the energy consumption structure and to reduce air pollution."

China expects to see five million electric vehicles on the road by 2020. The country plans to build twelve thousand charging stations and 4.8 million charging poles by the same year. Domestic companies are also encouraged to produce more electric vehicles, according to the Made in China 2025 plan.

With more electric vehicles running on the road, China will be better at dealing with pollution problems in the future, both home, and abroad.