The total number of electric buses in service is forecast to more than triple, from 386,000 in 2017 to about 1.2 million in 2025, equal to about 47 per cent of the global city bus fleet, according to a report from Bloomberg New Energy Finance (BNEF).

E-buses remain more expensive upfront than those fuelled by diesel, but BNEF found that battery-powered buses can already offer a lower total cost of ownership when fuel and maintenance expenses are factored in.

A typical e-bus with a 250kWh battery charging once per day at the depot and operating around 166km/per day has a total cost of ownership of €0.81/km ($0.99/km) – lower than diesel at €.0.86/km ($1.05/km).

According to BNEF calculations, every 1,000 battery-powered buses on the road will displace about 500 barrels of diesel fuel each day. This year, the volume of fuel that e-buses take off the market may rise 37 per cent to 279,000 barrels a day – approximately as much oil as Greece consumes.

China is leading the way on electrifying its fleet, adding 7,600 zero-emissions people-movers to its cities’ roads every month.

Austria, Germany, Lithuania, the Netherlands and Britain have collectively added almost 1,250 electric or plug-in hybrid buses to their fleets.

In a bid to improve air quality in Britain’s capital, London Mayor Sadiq Khan recently launched Europe’s largest fleet of all electric buses – a £19 million- (€21.7m, $26.5m) fleet of 51 Enviro 200 electric vehicles built by China’s BYD (Build Your Dreams) and Scotland-based Alexander Dennis Limited.

BYD has now supplied over 10,000 fully electric buses worldwide. The most extensive European order before London is one of 35 coaches delivered to Amsterdam’s Schipol airport.

Electric vehicles have proven their efficiency and capability and are now a serious competitive threat to traditional fossil fuel-powered vehicles. In September 2017, a heavy-duty Proterra electric bus set a new world record for the longest distance driven by an electric vehicle (EV) on a single charge, after covering more than 1,100 miles. This feat was made possible by its impressive 660kWh battery.

Major bus manufacturers are understandably keen to capitalise on the popularity of electric variants. In November 2017, Mercedes-Benz announced its intention to release an all-electric version of its popular city bus, the Citaro, starting in 2018. The Citaro has already found favour in public transport systems around the world, including London’s infamous ‘bendy buses’. It is the world’s best-selling bus, according to Mercedes.

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