Chinese bus manufacturer Zhengzhou Yutong Bus has chosen Maxwell Technologies' ultracapacitors for power supply and energy storage applications for its diesel-electric hybrid buses.
48-V ultracapacitor module
Zhengzhou Yutong Bus' hybrid drive system features 16 of 48 V ultracapacitor units of Maxwell Technologies to enable braking torque and energy recuperation assist functions that allow hybrid transit buses to obtain particulate emission reduction by a maximum of 90% and reduce fuel consumption and CO2 emissions by nearly 25% compared to traditional diesel buses.
Ultracapacitors, which store energy by means of an electric field, can be charged or discharged within a fraction of a second over a wide temperature range between −40° C and +65° C. It can function reliably through ³ one million charge/discharge cycles and has superior vibration and shock resistance. Maxwell Technologies' ultracapacitor cells are available in multi-cell modules ranging between 16 and 125 V and a capacitance range between 1 and 3,000 F.
Maxwell Technologies' ultracapacitors are used as a power source in around 4,000 hybrid transit buses that are currently in operation across the world, and are utilized in numerous other transportation uses, including a stop-start idle elimination system designed by Continental for micro hybrid diesel automobiles that are under production by PSA Peugeot Citroen in Europe.
Wang Feng, who serves as Overseas Marketing Director at Zhengzhou Yutong Bus, stated that the ultracapacitors' capability to charge and discharge quickly makes them to effectively intake regenerative braking energy and offer instantaneous power for acceleration. Moreover, they are cost-saving energy storage systems for hybrid buses due to their long operating life and minimal maintenance requirements, he added.