The adoption of any new technology involves some degree of adaptation, and battery electric buses (e-bus) are no exception. After decades of experience with diesel vehicles, cities and operators need to understand the technical and operational specifications of e-buses to align system planning, business models and service operations. A small challenge compared to the multiple benefits of transitioning to clean fleets.

Part of the process involves conducting tests or pilots. Those reduce risks and improve conditions for a successful transition, by allowing an understanding of the technology and assessing the performance of vehicle models available in the context of each city. This is what cities in China — the country with the largest fleet of battery electric buses globally — and Santiago, Chile, — one of the regional leaders in electrification — have done, for example.

A significant testing process recently concluded in Curitiba, Brazil. The city has taken several steps to decarbonize transport and conducted an operational demonstration of various e-bus models in 2023. In addition to generating localized information, the tests confirmed, alongside service customers, that electric buses can make public transportation more comfortable and attractive.

Curitiba's E-Bus Demonstrations

Curitiba aims to electrify two conventional public transportation lines and a Bus Rapid Transit (BRT) line. Between April and November 2023, the city tested seven vehicles from four manufacturers (BYD, Eletra, Marcopolo and Volvo). Each vehicle was tested for about 30 days. WRI Brasil supports the city under the TUMI E-Bus Mission and, together with URBS (the company managing public transportation in the city) and the Urban Research and Planning Institute of Curitiba (IPPUC), formed the team that monitored the tests.

The tests produced two main outputs. A technical report prepared by URBS compiled information from the tested vehicles, such as energy consumption, compliance with recommended autonomy and indicators related to charging infrastructure. Also, based on the QualiÔnibus Satisfaction Survey methodology, WRI Brasil helped capture and compile information on the perception of customers who used the tested electric buses.

This article delves into the crucial reasons for implementing tests on electric buses, drawing insights from key conclusions from Curitiba's experience.

Informing Those Operating the Service 

E-bus tests and pilots are comprehensive strategies with multiple benefits. They allow simultaneous exploration of available vehicle options, establishment of partnerships with manufacturers, presentation of electrification benefits to the public and learning for current operators of public transportation.

In Curitiba, the test vehicles were operated by the bus companies that constitute three consortia of the city's public transportation. The participation of these companies makes the tests more reliable and accurate due to their experience in operating services locally. It also enhances the operators' understanding of the technology for participation in future bidding processes. Thus, the city expands the possibilities of successful tenders.

Perception Research Reveals Acceptance of Technology

The C40 Cities guide, "How to Shift Your Bus Fleet to Zero Emission by Procuring Only Electric Buses," indicates that, in addition to generating data and information suitable for the local context, one of the main reasons for conducting pilots is to generate interest and confidence in the technology. Therefore, conducting perception surveys with service customers is valuable. This is an opportunity to check the population's prior knowledge about technology and measure the impact of vehicles on the perception of service quality.

WRI Brasil supported Curitiba in conducting perception surveys with passengers who traveled on five electric bus models — two from Marcopolo, two from Eletra, and one from Volvo. Conducted online, the surveys aimed to identify respondents' profiles, understand their experience and prior knowledge on the subject, their perception of seven key attributes of electric buses and their satisfaction with the vehicles. The survey yielded 506 responses, with 86% from people using the service three or more times a week. The sample consisted of 56% women and 43% men.

Comfort and Low Internal Vibration and Noise are Highlights

Of the participants, 78% were already familiar with electric buses and 22% became acquainted through the tests. Among the known or presumed benefits of the technology, the most mentioned (30%) was the reduction of local pollutants and greenhouse gas emissions, followed by noise levels (27%), charging costs (16%), energy consumption (14%) and maintenance costs (11%). The results demonstrate an opportunity to increase the population's knowledge about the benefits of electrifying public transportation.

At the same time, the research highlighted the positive impression generated by the demonstration. Of the participants, 9 out of 10 were supportive of deploying more electric buses. Almost all participants agreed with statements that the vehicles are quieter (95%), can contribute to air quality (94%) and benefit public health (89%). For 81% of respondents, electric buses are more comfortable than diesel ones, and 44% are willing to wait a little longer to board an electric bus.

When evaluating customer satisfaction with 14 aspects of the demonstrated vehicles, the final part of the survey made it clear that attributes directly related to technology were among the highest-rated. For example, smooth acceleration (90%), vibration (90%) and noise levels (90%), as well as ventilation and temperature (77%) — the latter favored not only by air conditioning but also by electric motors generating much less heat. The least well-rated items were vehicle capacity (58%) and safety (45%), which are independent of the technology.

The data is consistent with results observed in a pilot in Santiago, Chile, where public transportation customers gave electric vehicles a rating of 6.3 out of 7, higher than the rating for Euro VI buses — the most advanced diesel vehicles — which received a rating of 5.8.

Technical-Operational Tests

Equally important to customer perception is the verification of the operational performance of the buses. These tests allow the city to define specifications for battery electric vehicles for future public transportation contracts and tenders. They also allow for predictions of possible operational changes, alterations in routes and recharging strategy, as indicated by URBS's final report.

For each tested vehicle, Curitiba sought to measure characteristics such as energy consumption, compliance with manufacturers' recommended autonomy, tire wear, and other relevant chassis and body features. These measurements are opportunities for both the city to test and evaluate vehicle technical specifications and for manufacturers to adapt and improve their vehicles for Curitiba's operational context.

To meet the city's operational requirements, all vehicles had an autonomy declared by the manufacturer of at least 250 km, except for an articulated vehicle with a range of 200 km. In tests without load and with the air conditioning off, most vehicles met or exceeded the manufacturer's forecast, and only one conventional bus had autonomy about 20% lower.

But it is tests in normal operation, with passengers and air conditioning on, that provide more significant information for understanding vehicle performance and how operations and infrastructure can be structured. With the increase in weight and energy consumption, the autonomy of vehicles is significantly impacted. In Curitiba's tests, one of the vehicles did not meet the minimum efficiency defined in URBS's Fleet Specifications Manual for electric fleets and this means that the manufacturer must make adjustments to the technical specifications of the vehicle if it wants to enter the future tender.

Better for People, Nature and Climate

Tests, pilots and demonstrations of battery electric buses contribute to a smoother technological transition with fewer startles. More than that, when results are openly shared, as Curitiba did, they become valuable inputs for other cities that have also recognized the opportunity for decarbonization.