Carbon emissions from transport increased sharply in the 1990s and have since stabilised, yet are on a general upward trend

Greenhouse gases (GHG) from transport have risen almost 20% since 1990, now accounting for almost a fifth of the city’s 40 million tonne carbon footprint in 2018, according to new figures released today (27 June).

The government’s 2018 Greenhouse Gas Inventory shows transport accounting for 18.1% of total emissions, to 7.4 million tonnes, up from 6.2 million tonnes in 1990.

An Environmental Protection Department (EPD) spokesman said the transport figures did not include emissions from the electricity used to charge electric vehicles (EVs) – these emissions are counted under electricity generation.

Transit Jam estimates EVs accounted for only about 0.1% of the city’s electricity consumption in 2018, which would be the equivalent of around 26,000 tonnes of CO2 equivalent for the EV fleet. If every vehicle were electric-powered (and operating at the same energy efficiency as the 2018 fleet average and assuming a 90% charging efficiency), the total carbon footprint for the transport sector could be as low as 1.4 million tonnes, around 20% of the current number.

The government says EVs on trial in Hong Kong have delivered an improvement. “We estimated that local commercial EVs have about 30% less carbon emissions on average than their conventional counterparts (tank-to-wheel) on the same mileage travelled,” says an EPD spokesman, who says EVs’ carbon emissions will shrink further as Hong Kong phases out coal-fired power generation under its 2030 carbon reduction targets.

Electricity generation and Towngas production continue to be the biggest carbon emitter in the city, accounting for 65.6% (65.1% in 1990) of the city’s carbon footprint. But the government says the city has become more carbon efficient, with carbon intensity down 35.7% on 2005’s level: the city now produces 15 grammes of CO2e per HK$ of GDP.