Law on Hybrid Cars with Combustion Engines Switched off when Stationary

Mr Sitoh Yih Pin asked the Minister for the Environment and Water Resources whether section 21 of the Environmental Protection and Management (Vehicular Emissions) Regulations applies to hybrid cars which have their combustion engines switched off – with transfer to the use of an electric motor – when the car is stationary.

Under Regulation 21 of the Environmental Protection and Management (Vehicular Emissions) Regulations, it is an offence to leave the engine of a vehicle running when it is stationary for reasons other than traffic conditions. Leaving the engine running when the vehicle is stationary results in fuel wastage and unnecessary environmental pollution.

Hybrid vehicles are equipped with an internal combustion engine and an electric motor powered by a battery pack. If the battery pack is unable to meet the electrical energy needed to operate the in-vehicle auxiliary systems, such as the air-conditioning or the radio when the vehicle is stationary, the internal combustion engine will automatically re-start to provide the energy needed, thereby generating tailpipe emissions. Hence, hybrid vehicles can still emit tailpipe emissions when stationary and, thus, the regulations on idling engines also apply to hybrid vehicles.

To promote greater awareness of the regulation, NEA has installed anti-vehicle idling signages at places where vehicles frequently congregate, such as carparks, loading/unloading bays and along the roadside near schools. In addition, NEA also works closely with stakeholders, such as the authorised vehicle inspection centres, private and public transport operators and schools, to disseminate educational pamphlets and decals.