A number of European cities have committed to securing only zero-emission buses by 2025. However, to achieve this objective, manufacturers must make bold design choices, radically changing bus componentry, systems, and bodywork. Here, it looks at the debate for greater electric bus design standardization.
In a 2018 report on the Design of Urban Electric Bus Systems, a morphological matrix method was applied to illustrate the complexity of designing an electric bus system. All relevant electric bus technologies and charging systems were analyzed, leading to over 100,000 different system options which were theoretically possible and technically feasible. It is safe to say that the transformation process from diesel to electric bus systems opens up an extremely polarising design realm.
This design space offers bus original equipment manufacturers (OEMs) many opportunities to innovate, but prompts several challenges that also need addressing. Chinese bus OEMs have established conventional technologies and a world-beating cost base, thanks to large subsidies. This manufacturing knowledge has spread globally, with Europe selling over 1,800 electric buses in 2019 — an increase of 1,050 from the year prior. So, against this backdrop, is greater design standardization needed?
One standardization debate revolves around battery design — the chemistry and the placement. Battery chemistry has a direct impact on an electric bus’s range and charging speed — technology that has often fallen short. As a possible solution, next-generation battery technologies such as solid-state (SSB) and lithium-sulphur are gaining momentum, but with investments already made in Li-ion technology, how quickly can these alternatives be brought to market?