Maxwell Technologies Inc has received purchase orders valued at around $13.5million from three of China's leading transit bus producers.

The orders are for the company's BOOSTCAP ultracapacitor modules which support braking energy recuperation and torque assist functions in diesel-electric hybrid transit buses, indicating that China is serious about giving its public transport system a new, green look.

According to David Scramm, Maxwell’s president and chief executive officer, the ultracapacitors allow for efficiency in recapturing energy from braking and have low maintenance requirements. They allow for a long operational life and the BOOSTCAP modules have demonstrated reliable performance and high efficiency in the first wave of vehicles that have gone into service.

China's leading bus manufacturers have developed a number of electric and hybrid drive systems for cleaner and more efficient buses.

Through working with them, Maxwell Technologies hopes to expand its presence in the Chinese market with the company estimating that more than 150 hybrid buses featuring the technology are already in service and this number will grow to around 1,000 by the end of the year.