Shenzhen, China is the world’s first city to realize the full electrification of its bus fleet. Besides the fact that they’re quieter, the city’s 16,000 electric buses emit around 48 per cent less carbon dioxide and much fewer pollutants. They’re also cheaper to fuel and, with their streamlined engines, easier to maintain. (Shenzhen Bus Group, the largest of the three bus companies in the city, estimates that an electric bus costs approximately $98,000 annually, compared to $112,000 for a diesel bus.)
As they seek to curb carbon emissions, global municipal leaders are pledging to replace all or part of their city’s fleets with e-buses. But there are hurdles: upfront costs vary depending on location, but are approximately two to four times that of a diesel bus.
Pilot phases have also exposed e-bus shortcomings. They struggled on the rough roads in Bogota, Colombia, and on the steep hills of Cape Town. Albuquerque, New Mexico cancelled orders having found equipment problems in testing, and the batteries can struggle with extreme temperatures.
Then there’s the problem of infrastructure. E-buses need to be charged approximately every 200km, and chargers are expensive. They also use up a lot of space and power. Shenzhen’s fleet uses approximately 4,000 megawatt-hours (MWh), which is a lot when you consider that 1 MWh will power about 300 homes for an hour. “Buying the buses is one thing, but electrification requires you to change your whole business model and network,” says Joseph Ma, deputy general manager at Shenzhen Bus Group.
Accommodating its 6,000 e-buses required the company to build 106 charging stations with a total of 895 charging terminals. Each terminal costs £57,000. Seventy-four stations were installed in depots already owned by the company, but they also had to procure 32 new sites, lay kilometres of power cable, and rejig routes so that e-buses are never too far away from a charging station.
Nonetheless, e-bus numbers are rising, particularly across South America. Santiago, Chile has the largest fleet outside China; California and New York are moving towards an all-electric public bus fleet by 2040; and the number of e-bus registrations across western Europe tripled in 2019. Pune became the first Indian city to adopt e-buses in 2019, spearheading a national transformation.
Without government support, countries will struggle to realise full electrification. Several programmes have been set up to help cities overcome the upfront capital cost of e-buses, and the prices will also become more affordable with higher order volumes. “We’re looking at a world where almost all of our buses will eventually be electrified,” Ryan Sclar, a research associate for the World Resources Institute’s global electric mobility team, says. “Even beyond the environment, it increasingly makes good financial sense in the long-run.”
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