The First KMB Bus Equipped with Euro V Engine Running on Route B1

KMB is trialling its first Euro V engine on a KMB bus, making it Asia’s first double-deck bus with a Euro V engine. By effectively reducing the emissions of nitrogen oxides, the Euro V engine meets the latest and toughest emission standards in the world, contributing to a cleaner environment. The bus equipped with the Euro V engine is now running on Route B1 between Tin Shui Wai Railway Station and the Lok Ma Chau Spur Line.

In comparison with Euro IV engines, the Euro V engine excels in reducing the emissions of nitrogen oxides. The emissions of nitrogen oxides in the Euro V engine are reduced from 3.5 grams to 2 grams (in terms of kilowatts per hour), a reduction of 43%, while emissions of particulate matter, carbon monoxide and hydrocarbons are kept at the same level, 0.02 gram, 1.5 grams and 0.46 gram, respectively.

The Euro V engine is equipped with a Selective Catalytic Reduction (SCR) catalytic converter, which sprays a 32.5 urea solution into the exhaust gases. Ammonia formed from the urea triggers a chemical reduction reaction with the nitrogen oxides, converting them into nitrogen gas and water vapour. To meet the stricter emission standards for nitrogen oxides, the urea injection of the Euro V engine increases to around 5.5% from 4.5% in Euro IV engines.

In addition, the Euro V engine is equipped with a new generation monitoring system, namely the On-Board Diagnostics Stage II (OBD II), which is installed in the exhaust pipe. By monitoring whether the emissions of nitrogen oxides meet the Euro V standard, the system enables maintenance staff to check the emission performance of the engine and rectify any system faults immediately.

The first KMB bus equipped with Euro V engine is running on the road