Knowledge Management and Learning

Air pollution persists as a threat to the environment and the health and quality of life of Asia’s urban population. The World Health Organization estimates that more than 530,000 premature deaths in Asia are caused annually by urban air pollution.

Clean Fuels and Engine Technology Key to Better Air Quality

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Vehicles are almost always a major source of air pollution in Asian cities. Key emissions include carbon monoxide (CO), particulate matter, nitrogen oxide (N₂O), sulfur dioxide (SO₂) and volatile organic compounds including unburned hydrocarbons. Emissions of these pollutants depend a great deal on the quality of the fuels used, the engine technology, and the emission control devices used on vehicles.

Vehicle emissions in many Asian countries are expected to increase over the next few decades, as the vehicle population increases. If no action is taken to clean up fuels and vehicles, urban air quality will continue to decline. A key first step has been the worldwide drive to eliminate lead in gasoline, which has resulted in more than 90% of the world’s gasoline becoming lead-free. It is now time to address all fuel issues, including sulfur in fuel, additives, and other fuel components.

A regional road map for cleaner fuels and vehicles in Asia has been drawn with support from an ADB technical assistance for Better Air Quality Management in Asia.

How to Clean Up Fuels in Asia

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Cleaner fuels are a critical component of an effective clean air strategy.

This is the realization of pollution control experts worldwide over the past 30 years. Fuel quality is not only essential for directly eliminating or reducing pollutants such as lead, but also a precondition for introducing many important pollution control technologies (e.g., the lowering of sulfur content to enable use of diesel particulate filters). Asia must phase out leaded gasoline.

Fuels and vehicles are parts of an integrated system and must be addressed together.

Cleaner fuels, coupled with advanced emission control devices, will improve overall air quality and reduce emissions.

A program focused on cleaning up fuels and vehicles as a system can succeed.

Because most Asian countries have adopted European vehicle (Euro) emission standards, European fuel parameters are an important reference point. Fuel quality and emission standards in Europe represent an integrated approach to reducing air pollution from the transportation sector.

Once lead has been removed, sulfur levels in gasoline and diesel fuels are the primary fuel parameter to be addressed in developing a country’s fuel roadmap.

High sulfur levels reduce the effectiveness of three-way catalysts for gasoline vehicles and clog particulate filters in diesel vehicles.

The cost associated with producing low sulfur fuels is relatively small compared to changes in the global price of oil, and the public health benefits are certainly worth the investment.

The incremental costs of meeting the recommended level of fuel sulfur in Asia average $0.20–0.80 per liter for gasoline and $0.50–0.80 per liter for diesel. Further reductions to 10 parts per million or below would add about $0.60 per liter to the cost of diesel fuel.