Stoves and tankless water heaters running on gas will have to display energy efficiency labels in Hong Kong starting from September, marking the first time authorities are imposing such a requirement on non-electrical home appliances.

LED light bulbs would also be included in the expanded energy efficiency labelling scheme, which now involved 11 types of appliances, the Electrical and Mechanical Services Department said on Wednesday.

Director of Electrical and Mechanical Services Pang Yiu-hung said adding the three devices to the scheme would help reduce about 75,000 tonnes of carbon emissions each year and the expansion would cover approximately 80 per cent of household energy use, up from 50 per cent.

Appliances under the scheme are categorised into five grades, with grade one being the most energy efficient.

“Families will cut 20 per cent to 30 per cent of their expenditure on energy bills if they adopt products with the grade one energy label, compared with those with grade three labels,” he said.

The expansion will take effect on September 1, while manufacturers will have a 15-month grace period to adopt the scheme.

The mandatory energy efficiency labelling scheme was first introduced in 2009, covering air conditioners, refrigerators and compact fluorescent lamps. Such products must show labels indicating their energy performance and annual energy consumption.

Appliances are categorised into five grades, with grade one being the most energy efficient.

Washing machines, dehumidifiers, televisions, electric storage water heaters and induction cookers were subsequently included in the scheme.

Pang also said the department was considering introducing a minimum energy efficiency requirement for appliances under the scheme.

Assistant director Barry Chu Kei-ming said the department aimed to complete its research before 2024, and would discuss its findings with the industry and the Legislative Council afterwards.

In its Climate Action Plan published in 2021, the government said it planned reduce household electricity consumption by 15 per cent before 2035, and by 30 per cent before 2050.