Kowloon Motor Bus is determined to keep its cool when it comes to the environment.
All of its 3,600 air-conditioned buses now have sensors that fine-tune the inside temperature in response to the atmosphere outside.
The sensors save fuel as air conditioning is used only when it is needed.
Principal engineer Shum Yuet-hung said the cabin temperature was affected by the number of passengers, the air flow at bus stops and the temperature difference between inside and outside.
'The ambient sensor fine-tunes the temperature in the bus automatically to suit different cooling requirements based on the temperature difference,' he said. 'It enables the air-conditioning system to adjust its cooling according to actual needs and this helps save energy.'
Mr Shum said fuel consumption increased 1 per cent when the outside temperature increased by one degree Celsius.