Technology evaluation of Chinese hybrid electric bus demonstration

The development of new energy vehicles (NEVs) in China is important to address energy and environmental issues. Conducting product and technology assessments of NEVs will help accelerate improved performance and enhance demonstration policies and programs. Relying on the project of Ten Cities & One Thousand Units in 2009, this evaluation mainly focused on hybrid electric buses (HEBs). A comprehensive research framework was adopted, including on-road driving tests, daily operation data collection, and a questionnaire survey. The technology evaluation focused on operating performance, including vehicle reliability, energy consumption and its affecting factors, and emissions. We selected and assessed 44 HEBs in eight demonstration cities—Kunming, Hangzhou, Shanghai, Dalian, Ji’nan, Zhengzhou, Wuhan, and Zhuzhou, China. The evaluation covered 17 HEB models (including 11 propulsion systems) from 16 bus manufacturers. As with technological progress, in general, HEB technology has become increasingly mature, with a number of good HEB models emerging. The fuel efficiency of some domestically manufactured HEB models is close to the international advanced level. This evaluation provides a basis for decision-making and evidence of the need to modify Chinese HEB demonstration policy. Recommendations include the promotion of the technical application of idling start-stop and brake energy recovery, the expansion of demonstrations nationwide, and continuous financial support for HEBs.