In 2011, the electric-vehicle manufacturer BYD Auto unveiled an early model of an electric bus at an industry conference in Belgium. The head of BYD in Europe, Isbrand Ho, later recalled in an interview that, at the time, the launch was considered a joke; “everyone was laughing at BYD – for making a toy”. Just eight years later, major European cities are committed to electrifying their bus fleets; 240 electric buses will be running in London this year, and Paris has bought 1,000 electric buses which will start service in 2020. The rapid uptake of electric buses is occurring in cities around the world, with Bloomberg predicting that by 2030, 84% of global municipal bus sales will be electric.

The pace of the electric bus revolution has been most extraordinary in China. As electric buses produce zero tailpipe emissions, they have become a vital piece of the puzzle in solving China’s urban air pollution crisis. The first electric bus rolled off the production line and into use in 2009 in Shenzhen – the city where BYD is based. Less than a decade later, the full fleet of 16,359 buses in the city is now electric. As a result, while in most cities in the world air pollution has worsened over the last decade, in Shenzhen it has significantly improved. The Chinese Government has invested heavily in electric bus technology, infrastructure and incentives to scale up this successful pilot around the country. Every five weeks some 9,500 additional electric buses (the equivalent of London’s entire bus fleet) are deployed in China. Now 17% of China’s total bus fleet is electric. With 385,000 on the road, China is now home to 99% of the world’s electric buses.

Wider relevance

The electrification of public bus fleets holds massive potential to cut emissions of the greenhouse gases that cause climate change, as well as reduce the air pollution that curtails the lives of urban residents around the world. For every 1,000 electric buses on the road, about 500 barrels a day of diesel fuel are displaced from the market, according to Bloomberg New Energy Finance calculations. This means in that in 2018, electric buses displaced an estimated 233,000 barrels of oil. Where electricity is largely generated by renewable sources, as is the case in many Latin American countries, the switch to electric buses results in a steep reduction in greenhouse gas emissions. However, the superior efficiency of electric buses also means that even in the Chinese context, where the grid is still heavily reliant on fossil-fuelled power plants, carbon emissions have been cut simply by shifting from petrol and diesel to hybrid and electric buses.

What is particularly impressive about the rapid development of e-buses is the great technological leaps that have been made in such a short period of time. Issues that made reliance on electric buses for large scale public transport impossible just a few years ago – such as the limited range and long battery charging times – have more or less been solved in just a few years. A decade ago, an electric double-decker would have been unthinkable, as the size of battery needed to run such a large vehicle for long distances added too much weight to be viable. But technological improvements in the materials and efficiency of the batteries resulted in the pilot of the world’s first electric double-decker in London in 2016. The electric routemaster runs 180 miles on a single charge, meaning it can stay in service all day without having to recharge. Following this successful pilot, Transport for London (TFL) recently announced that 68 electric double decker buses will be joining the London fleet this year.

Electric buses are also more efficient than conventional diesel buses, and have received favourable reviews from users in pilots around the world. Electric buses are quieter, generating far less noise and vibrations than diesel buses, often making for a more comfortable journey. Although a simplistic, direct cost-comparison between electric and diesel buses still favours diesel as the more affordable option, studies have shown that if the “total cost of ownership” is considered – including the costs to society in terms of air pollution, noise and climate change – electric buses offer a much better deal.

Context and Background

The use of electric vehicles for urban transportation has a long history that predates gasoline and diesel-powered buses and, indeed, their displacement by planning that favoured private cars. In the late 1800s and early 1900s, most urban transport ran on electricity in the form of electric taxis and trams. However, the development of wide-ranging road infrastructure, and the discovery of petroleum reserves around the world made gasoline run vehicles more appealing and affordable in the second half of the twentieth century. This process was accelerated by automobile companies such as GM motors buying up transit firms producing electric street cars (trolleys) only to demolish the trolley lines, and replacing the trolleys with GM buses, coupled with a bigger, modal shift to the private car, also promoted by its manufacturers. As a result over 90% of America’s trolley system had been dismantled by the 1950s. This meant the development of electric vehicles stalled, only to be restarted at the turn of the 21st century, as the fossil fuel domination of public transportation became clearly untenable.

The transport sector currently accounts for 23% of global, energy-related carbon emissions. As such, it is clear that in order to achieve the goal set in Paris to limit global warming to well under 2 degrees, developed and developing country governments alike will need to make the rapid transition to zero emissions vehicles in the next two decades. Urban bus fleets offer a promising place to kickstart this transition, because many of the concerns about the viability of electric vehicles – such as the restricted range and recharging time – are quite manageable for urban bus services, which usually travel relatively short distances and return to the same bus station where recharging infrastructure can be installed. Another aspect of the current context is that in some countries like the UK, in the long shadow of the financial 2007-2008 crisis and the austerity measures imposed in its name, bus services have seen considerable cuts. But attitudes are now shifting and the UK’s opposition Labour party recently committed to reversing cuts and expanding bus networks. This creates further opportunities for electric bus expansion, a transport system described by Prof of Economics Simon Wren Lewis, as aiding both economic redistribution, activity and environmental improvement.

The speed of the transition to electric buses in China compared with the rest of the world can be chiefly explained by the gravity of the air quality crisis in Chinese cities since the 1990s, caused in part by tailpipe emissions from heavy vehicles. It has been estimated that urban smog was responsible for 1.6 million extra deaths in China in 2015. National and local authorities have identified electrification of public transport as a necessary means to protect the health of the country’s still booming urban population. In recent years, many cities across the industrialised and developing world have been catching up with China’s urban toxicity levels, so more and more municipal governments are looking to electrification of bus fleets as part of the solution to the mounting air quality crisis – which has been described by the World Health Organisation as “the new tobacco”.

Enabling factors

The scale of China’s investment in electric bus technology has greatly facilitated the speed of this rapid transition. Research and development have been occurring at a massive scale, led chiefly by Chinese companies like BYD, through the piloting, experimentation and phased roll-out of electric buses in China’s cities. This explains how issues around battery life, charging times and range have quickly been overcome. Electrification of bus fleets cannot be achieved in a single tender for most medium to and large cities. In China, as elsewhere around the world, the phased approach to roll-out of electric fleets has been critical. This allows cities to test the e-buses, make improvements and build local capacity of bus drivers, technicians and policy makers before they move on to deploy the technology at scale. This has been supported by electric bus manufacturers, who have been willing to loan their e-buses to cities for a pilot phase in order to help municipal governments test out and get to grips with the new technology.

Despite all the technological advances, electric buses are still expensive at face value and when social and environmental benefits are excluded, compared to their diesel counterparts – especially in terms of capital investment. An electric bus will typically cost roughly double the price of an equivalent diesel bus. As such, strong policy signals, subsidies and tax incentives have been vital to making electric buses a viable alternative for municipal authorities to invest in. Electric buses have been promoted in China since 2009 through up-front subsidies which make it cheaper to purchase an electric bus over a diesel or gas bus of the same size. The Government of California set a procurement mandate in 2000 that required municipal authorities with more than 200 urban uses to buy at least 15% zero emissions buses, and last year the state mandated a full shift to electric fleets by 2029. Similarly, in Sao Paulo, the city passed the Climate Change Law in 2009, calling for all fleets to run on renewable energy by 2018 – a goal that proved to be overly ambitious – but at the same sent a strong signal on the direction of travel of urban transportation in Brazil.

Although the upfront costs of electric buses are comparatively high, the running costs tend to be much lower than regular diesel buses, as electricity is usually cheaper than imported fuel and electric buses are much more efficient than internal combustion engines. As the procurement of electric buses by municipal governments soars around the world, the increased economies of scale mean that upfront costs are also set to decrease. Depending on the pace of growth of the European market over the next few years, it is estimated that battery prices for e-buses will decrease 9-12% annually up to 2030, representing a 75%-83% drop in the cost per kWh.

Scope and evidence

Every five weeks some 9,500 electric buses (the equivalent of London’s entire bus fleet) are deployed in China. Now 17% of China’s total bus fleet is electric. With 385,000 on the road, China is now home to 99% of the world’s electric buses.

The number of e-buses procured in Europe more than doubled in 2017 compared to 2016 – equivalent to around 9% market share of new registrations in 2018. As of mid-2018, there are around 1,600 electric buses on the roads of Europe and another 1,600 will be in use by mid-2019.

The Government of California set a procurement mandate in 2000 that required municipal authorities with more than 200 urban users, to buy at least 15% zero emissions buses. Last year the state mandated a full shift to electric fleets by 2029.

London aims to transition to an emissions-free bus fleet by 2037. Currently the London bus network uses 1.5 million barrels a year of fuel. Converting the TFL fleet to be fully electric will displace 430 barrels of diesel a day for each 1000 buses going electric, resulting in a 0.7% reduction in the UK’s total diesel consumption.

Lessons for rapid transition Sometimes you need to look back to look forward: in response to growing concerns over air pollution and climate change, cities are now returning to electric public transport – which has a long history predating the dominance of both cars and diesel fuelled buses. Staged pilots of e-buses help with roll-out: city planners, bus drivers, technicians and users all need to adapt to the shift in technology from diesel to electric buses, so time and experimentation are required for roll-out at scale. Cost projections should include the environmental benefits: an electric bus currently costs roughly twice the price of a diesel bus of the same size, so high upfront costs are the principal barrier to the pace of this rapid transition. However, a more realistic and inclusive calculation of costs – to include operational costs as well as costs to society including health, noise pollution and climate change – shows it is much cheaper to go electric.