Author: Bryan Chan

Date: 8/8/10


The main sources of air pollution in Hong Kong are from industry, transport and electricity generation [1] while sources of air pollution in Guangdong include inefficient coal-fired power plants lacking effective emissions controls, growing vehicle fleets, heavy industry and the manufacturing sector. [2]


An estimated 90,000 factories on the mainland are owned by Hong Kong interests. [3] In
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A cement factory in the north of Guangdong (19/1/08) - Alex Hofford (

particular, Hong Kong is the largest source of outside investment in Guangdong’s manufacturing with more than 53,000 plants there in 2003. [2]

While it is difficult for the Government of the HKSAR to influence the pollutants from mainland China (though the Pearl River Delta Regional Air Quality Plan is a useful first step), given the number of factories over the border owned by Hong Kong interests, the Government and the business community can clearly instigate significant change from within Hong Kong itself. [3] However, little has been done with Hong Kong-based firms which own polluting factories in Guangdong. [4]For example, the widespread use of bunker fuel and production of residual oil fly ash (ROFA) rich in metals is now one of the biggest threats to community health but also the most easily prevented. [5]


Cross-border Transport

In 2003 China became the third largest oil importer in the world (after the United States and Japan) and has become the second largest oil consumer (after the United States). [3] As the economy grows, an increased number of vehicles will result in a larger consumption of fuel. [6] Oil imports offer the potential to reduce pollution by sourcing higher graded oil. However, while importers must pay international prices, the state control on fuel prices have not allowed the costs to be reflected in the prices paid by consumers. [3] Indeed, sulphur level in fuels sold in China is 50-500 times higher than that in Hong Kong, where the ultra low sulphur diesel with 0.005% sulphur is the only diesel sold for vehicles. The price differential presents an incentive for cross-border commercial vehicles to fill up at mainland stations or buy from the illegal trade that supplies fuels with very high sulphur content. [6]

Roadside pollution


People covering their noses and mouths at roadside (23/3/10) - Alex Hofford (

Street-level pollution is a major air quality problem in Hong Kong. [3] An estimated 50% of Hong Kong’s population live and/or work in roadside environments. [5] Transport emissions have been shown to be the most important determinant of daily air quality for approximately 50% of the time in Hong Kong [7]. The roadside NO2 and PM10 concentrations remain high and harmful to human health, and SO2 concentrations are edging up. [3] Although ozone is not emitted directly from motor vehicles, it is formed in the atmosphere mainly by reactions between nitrogen oxides and hydrocarbons emitted from motor vehicles. [8]

Motor vehicles, especially diesel vehicles, are the main causes of high concentrations of respirable suspended particulates (RSPs) and nitrogen oxides (NOx) at street level in Hong Kong. In fact, roadside emissions account for 1% of sulphur dioxide emissions, 23% of nitrogen oxide emissions and 31% of particulate matter emissions in Hong Kong. [9]

The Government introduced a programme in 2000, aiming to reduce RSPs and NOx from motor vehicles by 80% and 30% respectively by the end of 2005. [7] However, compared with 1999, the respirable suspended particulates (RSPs) and nitrogen oxides (NOx) had only been reduced by 22% and 23% respectively in 2008. [10]

Restrictions on private cars may not lead to significant reductions in regional pollutions because the major emission sources in HK are from marine, commercial vehicles and power generation. [11]

Although diesel vehicles account for only one-third of the vehicle population (30% of all vehicles [12]), they are a major source of air pollution because they make up two-thirds of the vehicle mileage travelled in Hong Kong and emit a considerable amount of respirable suspended particulates and nitrogen dioxide. [13] Indeed, Hong Kong’s commercial diesel fleet (franchised public buses, non franchised public buses and commercial light and heavy vehicles) is responsible for 90% of RSPs (i.e. suspended particulates smaller than 10 micrometers that have the ability to penetrate deep into the lungs), and 80% of nitrogen dioxide emissions from the entire road transport sector. [14]

Public transport in Hong Kong is successful. Every day over 11 million passenger trips are made, which accounts for over 90% of daily traffic. However, “dirty” public transport is a serious threat to Hong Kong’s environment, especially air pollution. In particular, heavy public buses are responsible for some of the most harmful emissions in terms of proximity to the population and continuous emissions in terms of operational hours, thereby contributing to about 40% of roadside emissions. [14]

As of February 2009, 4,511 of Hong Kong’s 5,768 franchised buses – approximately 77% of the franchised bus fleet, are still Euro II or below. Based on the age distribution of the existing franchised buses, it is anticipated that all the pre-Euro, Euro I and Euro II buses will retire by 2012, 2015 and 2019 respectively, while Euro III buses will retire by 2026. [14]

Marine pollution


Smoky emissions from a vessel in Hong Kong - Alex Hofford (

Marine emissions account for 5% of sulphur dioxide emissions, 9% of particulate matter emissions and 18% of nitrous oxides in Hong Kong. Ships in Hong Kong currently use fuel with 4.5% sulphur content, or even higher. [6]


The Kwai Chung container port (20/7/09) - Alex Hofford (

The highest growth rates of SO2 emissions are concentrated in areas close to marine activity and the container terminals in Kwai Chung, Tsuen Wan and Sham Shui Po. [3]Moreover, ships offload containers close to the city centre and shipping accounts for a high proportion of all CO2 emissions on smoggy Hong Kong Island. [15]


Many cities are unable to meet air quality standards due to greater demands on energy consumption – this has happened in Hong Kong and Shenzhen, where there has been tremendous growth in the last two decades. [6]

By raw tonnage, electricity generation is the biggest source of air pollution in Hong Kong. [3] The power-generation sector’s contribution to pollution has been rising again over the past four to five years. It is possible that growing electricity demand from different sectors is outweighing emission-reduction benefits gained via various pollution control measures and the commissioning of gas-fired plants. [3]

Power demands in the Pearl River Delta

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A cement factory in Northern Guangdong (19/1/08) - Alex Hofford (

In 2003 the manufacturing industry in Guangdong consumed 205 PJ of fuel oil and 152 PJ of diesel fuel. This was 78% as much fuel oil as used for public power generation, and 90% as much diesel fuel as consumed by transport. Manufacturing is also responsible for 75% of all coal use in Guangdong. Coal will remain the major source of power generation and a major industrial fuel in Guangdong. Those sub-sectors relying on coal or heavy fuel oil are likely to continue to self-generate their own power because it is cheaper. [2]

Cost and availability are broadly encouraging the use of fuel oil with higher sulphur content. For many firms, energy is a small enough part of their operating budget so they can absorb a moderate price penalty for cleaner fuel if necessary. [2]

Many factories self-generate power but this is more costly than getting power from the grid – self-generation provides backup during power shortages and greater control over production. The constraints on public power supply are not only ones in generation, but in some cases, of transmission line capacity. For example, in Guangdong, manufacturing has grown so rapidly that local energy infrastructure is unable to keep pace, resulting in reliance on non-official energy sources. Moreover, as local grids are not well interconnected, supply is highly localized. In some cases power is directed to preferred customers (with long established factories) that leads to lack of supply of official fuel – as a result, the gap in supply relative to demand for particular types of fuel tends to be filled by local private refineries who provide fuel of lower quality. Suppliers and traders believe that as much as 40% of the oil products in Guangdong today come from non-official sources. [2]

To initiate a widespread clean up, higher quality fuels must be readily available. This is unlikely until price controls are eased as higher energy prices are providing an incentive for manufactures to switch to cheaper dirtier fuels. As a result, voluntary measures alone are unlikely to create a substantial demand for higher priced cleaner fuels. [2]

Local power


Coal at the Hong Kong Electric Lamma Power Station (29/7/10) - Alex Hofford (


Hong Kong Electric's Lamma Power Station (29/7/10) - Alex Hofford (

Emissions from electricity generation account for 32% of particulate matter, 44% of nitrogen oxide and 89% of sulphur dioxide emissions in Hong Kong [7]

46% of Hong Kong’s primary energy need comes from coal. Coal makes up 39% of China Light & Power’s fuel consumption and 100% of Hong Kong Electric’s. [3]


  1. ‘Where does Hong Kong’s air pollution come from?’, Hedley Index FAQs - last accessed 6/8/10
  2. 2.0 2.1 2.2 2.3 2.4 2.5 ‘Owning up to Responsibility for Manufacturing Contributions to the Pearl River Delta’s Poor Air Quality’, Bill Barron, Simon NG Ka Wing and Ben LIN Chubin, March 2006 - last accessed 8/8/10
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 ‘Boomtown to gloomtown – The implications of inaction’, CLSA – Christine Loh, James Paterson, September 2006 - last accessed 4/8/10
  4. ‘Comments on a proposal for reviewing the air quality objectives and developing a long term air quality strategy’, Civic Exchange, 18 September 2006 - last accessed 8/8/10
  5. 5.0 5.1 ‘Air Pollution: costs and paths to a solution’, Department of Community Medicine, HKU, Department of Community and Family Medicine, CUHK, Institute for the Environment, HKUST, Civic Exchange, June 2006 - last accessed 8/8/10
  6. 6.0 6.1 6.2 6.3 ‘The air that we breathe’, CLSA, April 2005 - last accessed 8/8/10
  7. 7.0 7.1 7.2 ‘A Price Too High: The Health Impacts of Air Pollution in Southern China’, Civic Exchange, HKU Medical Centre, Department of Community and Family Medicine, CUHK, Institute for the Environment, HKUST, June 2008 - last accessed 8/8/10
  8. ‘Air pollution caused by motor vehicles and construction activities’, Environmental Protection Department, September 1997 - last accessed 8/8/10
  9. ‘Reducing emissions from vehicles’, EPD website - last accessed 8/8/10
  10. ‘A comprehensive vehicle emissions control programme’, EPD website- last accessed 8/8/10
  11. ‘The Sustainable Development Council Invitation and Response Document: Clean Air-Clear Choices - Will High Air Pollution Alert Days provide an efficient path to health protection?’, Department of Community Medicine, HKU, The Air Quality Objective Concern Group
  12. ‘Actions to improve Hong Kong air quality’, Planning, Environment and Lands Bureau June 1999 - last accessed 8/8/10
  13. ‘Background brief on Trial Scheme of LPG & electrified light buses’ Legislative Council Panel on Environmental Affairs, 3 July 2001 - last accessed 8/8/10
  14. 14.0 14.1 14.2 ‘Paying for a Cleaner Bus Fleet: How Government can Break the Long Jam’, Eric Heimark, Helena Lalogianni, Mike Kilburn and Christine Loh, November 2009 - last accessed 8/8/10
  15. Air Pollution Hong Kong - Help us Clear The Air’, Clear the Air - last accessed 8/8/10