Hong Kong’s hybrid electric buses found to use more fuel than normal ones

Hybrid electric double-decker buses actually guzzle more fuel than conventional buses because of Hong Kong’s hilly roads and hot weather, according to preliminary results from an ongoing trial.

Environmental Protection Department officials admitted the six hybrid buses, trialled over a year, were “not as efficient as they thought”. They pointed to heavy use of air conditioning systems, which accounted for up to 40 per cent of the energy used in the summer.

Although fuel performance was better in winter, the buses still used 3.4 per cent more fuel on average than regular buses.

“The numbers don’t look satisfactory right now,” assistant director for air policy Mok Wai-chuen told the legislature’s environmental affairs panel on Wednesday.

“Because buses in Hong Kong use a lot of energy in air conditioning, the benefits of the hybrid mode are not maximised. We are allowing [the manufacturer] time to improve designs … and will come back to report on this later.”