According to the Department of Transport, a town with 200 electric buses could reduce its CO2 emissions by around 7,400 tonnes a year. That would be equal to taking 3,600 diesel cars off the road. The environmental incentives are obvious, so why not full charge ahead? Here, Roger Brereton, head of sales at steering system specialist Pailton Engineering, explains some of the technological barriers to the widespread adoption of electric buses.
Approximately 17 per cent of the world’s buses are electric and the e-bus market is growing. Governments are keen to offer incentives for electrification. In the UK, for example, the government has offered £50 million to towns pledging to create 100 per cent electric bus fleets.
Electrification of buses might appear to be the perfect answer to help achieve emission reduction targets, but its implementation is more complicated than it first appears.
Many of the challenges are infrastructural. E-bus fleets need a large number of charging points and policy-makers are trying to keep up. Charging ports and the facilities that house them are expensive and require the reallocation of land in dense urban areas. If ports and other charging facilities are thin on the ground, e-buses will not be able to offer longer routes and service flexibility.
While lack of charging ports is the most acute problem, it is not the only one. When e-bus adoption is scaled up, it will significantly increase demands on local power grids. At that stage, grid instability might also become a problem. Fortunately, most cities have interconnected systems to address these problems in the grid network. However, this will remain a barrier to electrification in those places with inadequate electricity networks.
There are also technological barriers inherent in the buses themselves. The batteries have limited power and range. Longer routes and steeper topographies are therefore problematic. This is a technology in its infancy and continued innovation through pilot schemes will be necessary to overcome these teething issues.
As bus manufacturers take on these challenges, there is also an opportunity for companies to make the most of the new design realm of electric buses. With chassis design revolving around battery placement, a factor that many bus manufacturers have taken different stances on, one electric bus could look incredibly different to another.
It is crucial that bus manufacturers have access to design flexible suppliers, with equal focus on quality. For example, Chinese company BYD’s electric buses, which were designed for the Chinese market, encountered unanticipated technical issues when they were piloted in Bogotá, the Columbian capital. The e-buses designed for the Chinese domestic market were ill-suited to the driving style and conditions in Columbia.
The Bogotá case highlights the importance of high-quality conventional components, amid the electrification hype. Furthermore, demand for reliable parts will increase when battery technology makes anticipated improvements. The next generation of batteries may last longer than your traditional diesel engine, but the other components that make up the bus will need similar longevity to take advantage of this longer lifecycle.
As the industry aims to make widespread electrification a reality, massive infrastructural projects will be necessary to ensure the buses are properly charged and can compete with their traditional equivalents in terms of route distance and flexibility. Designers and manufacturers of e-buses will have to be creative in overcoming some of the technical limitations of the buses themselves. This will require design flexibility, innovative pilot schemes and high-quality components. Once that is ensured, it will be full charge ahead toward the environmental benefits of widespread electrification.