Injector with regular diesel

Shell Hong Kong Limited (“Shell”) has recently collaborated with The Chinese University of Hong Kong (CUHK) by providing technical support to CUHK’s Security and Transport Office and introducing Shell FuelSave B5 Diesel to the instution. This collaboration has successfully solved the long-standing problems of engine failures and smoke emission of campus buses.

Students of CUHK generally rely on timely transportation for their campus activities, however breakdowns of regular diesel-using campus buses occurred from time to time, emitting black smoke from the exhaust and delaying engine response when accelerating. Frequent breakdowns disrupted the bus schedule, causing inconveniences to students and drivers. Shell’s Account Management and Technical team therefore offered their technical services to the Security and Transport Office of CUHK to investigate the root cause.

Both parties inspected the fuel injectors of the impacted buses and found significant accumulation of carbon deposits on the fuel injector nozzles and piston heads – a common cause for poorer combustion, higher fuel consumption and higher CO2 emissions. Poor combustion can also result in partially burnt fuel being emitted from the exhaust as black smoke.

Shell proposed a trial of selected buses converting from regular diesel to Shell FuelSave B5 Diesel with DYNAFLEX Technology1. Within only 20 days from the switch, the injectors were seen to be noticeably cleaner and with fewer deposits. In a following longer-term trial, it demonstrated even more noticeable reduction in carbon deposit build-up on the critical fuel system components2. The Security and Transport Office of CUHK was pleased to witness the trial outcomes, they indicated that biofuel helps to upcycle domestic waste materials, tackles both local waste and CO2 emissions, while providing energy security locally. Following the trials, CUHK made a decision to switch to Shell FuelSave B5 Diesel for its entire campus bus fleet, which successfully reduced CO2 emissions and black smoke from the buses, resulting in a cleaner campus environment, breakdown frequency was also reduced.

Shell FuelSave B5 Diesel includes 5% of biodiesel and 95% diesel. Biodiesel is recognised by the Hong Kong Government as a form of renewable energy, it is mainly produced from locally collected waste cooking oil and grease trap oil. Biodiesel can contribute to reducing greenhouse gas emissions, by helping reduce the overall CO2 emissions on a well-to-wheel basis, compared with using conventional regular diesel.

Media enquiries:

Ting Hoo
External Relations Manager
Shell Hong Kong Limited
Tel: 2506-7341

DYNAFLEX technology or DYNAFLEX formulation are our names for our latest generation of advanced formulations for gasoline and diesel fuels. See for more information.

Compared with regular diesel as experienced by the customer rather than Shell protocols. Benefits will vary according to type of operation, vehicle, driving conditions and driving style.

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