China’s electric vehicle maker BYD opened its first commercial monorail on Friday, as part of its efforts to diversify into mass transit and compensate amid a slump in sales of electric cars.

BYD is billing “Skyrail” as cheaper than the subway and without the traffic problems of buses. It is aimed primarily at Chinese cities, where congestion and pollution are endemic, but it also plans to export the system. 

The first such monorail went into operation in the Northwest provincial capital of Yinchuan on Friday after a brief ceremony Thursday. BYD says it has interest from more than 100 cities for the system, including New York and Cape Town in South Africa. Part of the attraction is cost — one-fifth of the capital costs of a subway system, according to BYD, and it takes a third of the time to build. Twenty cities, mainly in China, plan to build one in the coming year, BYD said, and its first foreign customer will be the Philippine city of Iloilo.