Can electric vehicles steer Hong Kong towards better air quality?

“The air is especially bad since I’m right next to the road and facing the sea. There is a lot of dust and fumes from cars and ferries, but I’m used to it,” she told Eco-Business, stressing that the only way she can deal with the pollutants from traffic is to sometimes put on a face mask. 

The news vendor’s gripe is a common one that would resonate with much of the city’s urban-residing population of more than 7 million, many of whom live in high-rise buildings closely stacked and that sit along busy and often polluted streets. 

Hong Kong’s air quality – take roadside nitrogen dioxide (NO2), for example – now far exceeds thresholds set by the World Health Organisation by up to 550 per cent, according to the Annual Air Quality Review by non-profit Hong Kong’s Clean Air Network released in January. 

The same study found that roadside concentrations of PM 2.5 – particulate matter smaller than 2.5 micrometres, such as smoke, vehicle exhaust or industrial emissions – are 304 per cent above guidelines set by WHO’s Air Quality Guidelines (AQGs).

NO2 is a pungent and corrosive gas mainly formed through the combustion of fossil fuels like diesel, making diesel-powered cars, lorries, and buses major sources of NO2 emissions in the city. Hong Kong’s transportation sector accounts for the second largest share of its total greenhouse gas emissions; commercial vehicles such as buses only account for 20 per cent of the total number of vehicles in the city, yet contribute over 90 per cent of NO2 emissions. 

Another resident by the name of Athena told Eco-Business that due to the city’s road transport planning, Hong Kong’s air quality has hardly improved over the decades.

She believes the government should first tackle pollution from public buses. “It affects the environment the most,” she said. 

Low-carbon transport

There have been some policy movements to improve transport planning, such as the Green Transformation Roadmap of Public Buses and Taxis, announced in December 2024, which will see the Hong Kong government subsidise the purchase of an additional 600 electric buses and 3,000 electric taxis, and install at least 500 fast electric vehicle (EV) chargers by the end of 2027. Hong Kong has a fleet of nearly 6,000 licensed buses. 

The policy follows the city’s Clean Air Plan for Hong Kong 2035, which was released in 2021, and outlines aims for Hong Kong to become a more liveable city with air quality comparable to major international cities by 2035 and to meet the WHO’s AQGs in the long term. Hong Kong’s air quality management pales when compared to other cities such as Singapore, Tokyo and Taipei. 

Clean Air Network (CAN)’s chief executive officer Patrick Fung told Eco-Business that he believes current plans to transition to EVs and hydrogen fuel cell vehicles must be more ambitious and the government should look at addressing emissions from heavy vehicles. 

He noted that the government’s roadmap fails to mention whether commercial minibuses – which collectively cover thousands of kilometres each day – will see any enhancements. “By 2027, less than one-fifth of franchised buses and less than one-third of taxis will transition to electric or hydrogen [vehicles],” he said. 

“Additionally, there are other commercial vehicles like lorries, where trials have been unsatisfactory, making it difficult for operators to switch from diesel or hybrid to electric or hydrogen,” he added. 

Citing how air pollution has been blamed for more than 3,500 premature deaths in 2024 alone – a decrease in numbers compared to 4,900 preventable deaths in 2019, but nonetheless unsettling –  Fung said the problem should be urgently addressed. “From a health perspective, we remain concerned about the NO2 levels…We’ve been discussing this (issue) for nearly 10 years now,” he said. 

Costly overhaul

Another barrier in the way of replacing Hong Kong’s bus fleet is a lack of financing. The city needs over HK$771 million (US$6 billion) to overhaul its diesel-powered double-decker bus fleet for it to be fully powered by hydrogen, according to a December 2024 report by Civic Exchange, a local think tank. 

Hong Kong launched its first commercial electric buses in 2022 and its first hydrogen-powered buses in 2024. Hydrogen buses were introduced later amid the lack of EV charging infrastructure. 

The hydrogen-powered buses work by converting hydrogen into electricity through a chemical reaction in a fuel cell, producing only water and warm air as emissions. Only around 100 of the city’s nearly 6,000 buses are electric, fewer than 10 buses are hydrogen fuel cell-powered.

There are fewer than 10 hydrogen fuel cell-powered buses in Hong Kong. Image: LN9267 / Wikimedia Commons

According to Hong Kong’s Environmental Protection Department’s (EPD), the city is currently focused on phasing out around 40,000 commercial vehicles running on Euro IV diesel and requiring buses to comply with stricter Euro VI standards, which emit roughly two-thirds fewer emissions. 

The Civic Exchange study notes that current models to cover overhaul costs, such as through “fare box” income – or the revenue generated from passenger fares – are far from enough.

The government should focus on setting clear policy targets or building confidence among manufacturers that Hong Kong will transition to electrification, including hydrogen- and battery-powered electric vehicles, Lawrence Iu, executive director of the Civic Exchange, told Eco-Business.

“This is necessary because if the government makes a commitment, it will help bus companies negotiate with manufacturers, ultimately reducing the cost of buses and the transition itself,” Iu said.

Government funding, Iu noted, would not be a long-term solution, as current agreements of Hong Kong’s bus franchise – which is privately owned – allow operators to continue making commercial decisions; it could potentially undermine how bus operators choose to upgrade the technology of buses based on operational needs and would allow the public sector to “interfere” down the line.

Instead, the Civic Exchange report calls for short-term government subsidies to cover the difference in capital expenditure and fuel costs, and for new buses to be leased instead of purchased, among other recommendations.

“If the government provides anymore more subsidies to the industry, it will gain more control, which is not beneficial for the healthy development of the bus industry,” Iu added.

The Shenzhen comparison

The shortcomings of Hong Kong’s transport electrification plans become more stark when seen alongside Shenzhen, the first major city in the world to have electrified all its public buses – as early as in 2017. 

The southern Chinese metropolis, just roughly an hour away from Hong Kong, has also electrified its entire taxi fleet in 2019. With these developments, it has cut its average air pollution levels by half. 

The rapid electrification of vehicles in Shenzhen can be attributed to the policy push by the central government, said Vincent Yip, chief executive officer of Cornerstone Technologies, a Hong Kong-based company that provides EV charging solutions.

“For example, one can obtain (driving) licenses more quickly by purchasing a new energy vehicle (NEV) in China, which has essentially made most new cars EVs. Another policy (saw) significant subsidies for EV charging infrastructure, particularly in Shenzhen over the past years,” he said.

The subsidies have led to a network of over 420,000 charging points found throughout the city, with many allowing vehicles to “fast-charge” their batteries up to 80 per cent in under 10 minutes.   

“All these factors have helped to eliminate doubts people may have had about switching to EVs and reinforced the development of the ecosystem,” Yip added.

China also views its EV sector as a core “pillar” to drive economic growth, noted David Zhang, a Shanghai-based EV expert and automotive analyst.

A row of taxis in Shenzhen. The city electrified its entire taxi fleet in 2019. Image: The Transport Enthusiast DC / Unsplash

“Shenzhen has rapidly developed its EV [sector] and sees it as a core industry to drive GDP growth,” he told Eco-Business.

Other Chinese cities, apart from Shenzhen, have also seen a rapid rise in EVs because of policy adjustments. “Tier 1” or economically influential cities such as Beijing, Shanghai, Guangzhou, and “Tier 2” cities like Hangzhou, Chengdu, and Suzhou have all seen increases in NEV registrations, with the entire nation’s EV sales overtaking conventional vehicle sales in mid-2024.

China’s government recently announced that it would pivot away from traditional industries to focus on innovation and technology, particularly in artificial intelligence (AI), energy, and electric vehicles, as part of its “new quality productive forces” concept to bolster economic growth.

New nationwide policies, such as the country’s “Old Car Exchange Programme,” which was introduced in 2024, are also helping to accelerate EV adoption, Zhang noted. The vehicle trade-in scheme sees consumers eligible to receive a subsidy of up to 20,000 renminbi (US$2,730) when they trade their old ICE vehicle for a new EV.

Companies like Shenzhen-based BYD, which is now the world’s largest EV maker, have greatly contributed to the city’s GDP and led to employment opportunities, Zhang added.

“As a result, Shenzhen has one of the highest concentrations of EVs in China, particularly in commercial logistics vehicles,” he said.

Incentives to drive charging 

In Hong Kong, EVs represent just over 12 per cent of all private vehicles as of January 2025 – up from 11 per cent in 2023 – and account for over 60 per cent of newly registered cars in the city.

While these numbers appear encouraging, current EV policies and high charging costs are deterring many would-be drivers from adopting an EV. Hong Kong’s power company CLP, for example, announced in March 2025 that it would start charging customers a fee to charge their vehicles, ending 16 years of free service.

Tax incentives for first-time EV registrations, or those replacing their internal combustion engine (ICE) car with an EV, have also been reduced by 40 per cent over the years. This is discouraging, notes Cornerstone Technologies’ Yip.

“Government policies like tax incentives for private vehicles can stimulate change. When the incentives were high, with reductions up to HK$280,000 (US$36,090) for exchanging an old ICE car for an EV, that encouraged customers to switch,” he said. 

Despite the lower incentives, EV sales now outsell ICE vehicles in Hong Kong, which will increase demand for charging stations, making the lack of EV charging infrastructure another challenge.   

There are over 112,000 EVs in Hong Kong and roughly 10,400 public EV chargers available, or about one charger for every 11 EVs. 

The need to retrofit old parking spaces with electricity outlets powerful enough to charge several EVs at once is one reason why charging infrastructure cannot simply be built in any location, Yip adds. 

Being unable to fit EV charging stations into residential and commercial buildings could lead to an estimated shortage of 170,000 charging points by 2040, according to a 2024 CBRE study. 

But Iu believes that there are already enough EV chargers for private cars, given Hong Kong’s small size, but not for commercial vehicles. “The average daily mileage of a private car is around 50 kilometres, meaning each vehicle needs to charge two to three times per month. So current charging infrastructure is sufficient for most new users in Hong Kong,” he said. 

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If Hong Kong really wants to reduce roadside emissions or greenhouse gas emissions in the long term, the city must rethink its transport system.

Lawrence Iu, executive director, Civic Exchange 

Maintain focus on vehicle emissions 

On Hong Kong’s air pollution problem, an EPD spokesperson told Eco-Business that even as the city’s air quality has exceeded WHO guidelines, the levels still meet the city’s own Air Quality Objectives, which are “tailored to take account of Hong Kong’s unique urban context and economic scale.” 

The spokesperson added that Hong Kong has seen its air quality improved in the last two decades. “The annual average concentration of ozone (O3) has gradually turned steady in the past few years,” said the spokesperson, referring to a pollutant that also comes from vehicle emissions, as well as industrial processes.  

“Despite the increase in regional ozone levels, the significant improvement in Hong Kong’s air quality has resulted in over 50 per cent reduction in the associated long-term health risks in the past 20 years,” added the EPD representative.

Civic Exchange’s Iu suggested for the city government to encourage residents to rely less on private and commercial vehicles for transport, and more on its railway system, until Hong Kong manages to better implement its plans. Hong Kong’s rail system ranks as one of the most efficient systems globally, handling more than 5 million passenger trips each day. 

“If we can shift our focus so that private and commercial vehicles are used less frequently – perhaps only 10 per cent of the time – and encourage more corporate entities to use public transport, which currently accounts for about 30 per cent of commutes, this would be very helpful,” Iu said.

“If Hong Kong really wants to reduce roadside emissions or greenhouse gas emissions in the long term, the city must rethink its transport system.”

*One name has been changed in this article to protect the anonymity of an interviewee.