Hanoi's alarming air pollution is a hot topic on the sidelines of the Environmental Seminar with the theme "Science and Innovation for a Sustainable Future", taking place on the afternoon of December 4, within the framework of VinFuture Science and Technology Week 2025. According to international scientists, electric vehicles are the key to solving this problem.
Old motorbikes cause more pollution than gasoline cars
Hanoi's air pollution is quite serious, just breathing makes it felt right away, Dr. Filippo Giorgi, Abdus Salam International Theoretical Physics Center (Italy), shared after a few days in Vietnam attending VinFuture Science and Technology Week 2025.
During his days in Hanoi, he noticed that fog was quite common. However, the expert warned that it is not normal fog but caused by pollutants. When the eye cannot see the sky and buildings, it is a sign that the air is heavily polluted.
Dr. Filippo Giorgi said that Beijing (China) had previously experienced an environmental crisis that was even worse than what Hanoi was facing. However, they quickly recognized the cause and had strong, synchronous solutions to overcome it.
So I think the first priority in Hanoi is to solve the problem of air pollution, because this is the third most common cause of premature deaths, Dr. Filippo Giorgi proposed.
One of the reasons that the Italian expert mentioned is that the Do is the huge number of gasoline-powered motorbikes in circulation, which has pushed Hanoi's air quality to the alarming level. In particular, he emphasized the environmental risks of used vehicles because "old motorbikes are more heavily polluted than gasoline cars".
According to the Hanoi Department of Construction, the city currently has 6.9 million motorbikes and approximately 1.5 million motorbikes from other provinces regularly operating in the area, of which 70% of the motorbikes in circulation are used vehicles. Motorbikes and scooters account for 95% of motor vehicles.
Studies show that motorbikes are the main source of emissions in urban areas. Specifically, the two-wheeled waste dischargers cause 94% of hydrocarburide (HC), 87% of CO gas, 57% of NOx and 33% of PM10 fine dust from traffic.
Experts recommend that continuing to use millions of old motorbikes not only reduces air quality but also directly affects people's health.
UNICEF recorded about 70,000 Vietnamese people dying each year from air pollution-related diseases, meaning an average of one death per 7.5 seconds due to a "silent killer".
Electric vehicles are the solution to Hanoi's pollution problem
Dr. Filippo Giorgi highly appreciated the fact that the Vietnamese Government as well as Hanoi City are strongly promoting the replacement of gasoline motorbikes with electric motorbikes.
He said that the first benefit of the conversion is that Vietnam will save a lot of energy because electric vehicle engines consume less energy than gasolineoline vehicles' internal combustion engines. The expert believes that now is a key time for Hanoi to improve air quality, in which replacing gasoline vehicles with electric vehicles is a good solution.
To make the transformation process truly effective, the government needs to have support policies and incentives for people to reduce costs, he raised the issue.
Also related to energy conversion, Prof. Aldo Steinfeld, ETH Zurich (Switland), Winner of the SolarPACES lifetime Achievement Award of the International Energy Agency (2024), said that biofuel is not an effective alternative to traditional gasoline.
In essence, biofuel is produced by mixing mineral gasoline with an alcohol concentration of biofuel (ethanol). This biological waste is made from natural materials, such as cassava, corn, sugarcane, algae, or other agricultural waste. Although it emits less than mineral gasoline, the replication of this fuel is very limited, unable to meet the world's consumption needs.
"We need a large area of land to grow biomass to serve biofuel production. That will compete directly with land used for food cultivation, said Prof. Aldo Steinfeld analyzed.
Prof. Aldo Steinfeld also mentioned a research he has been pursuing for 20 years, which is sustainable aviation fuel produced from water and CO2 in the air. However, he assessed this as a very expensive fuel, the production cost of 1 liter is 4-6 times higher than that of fossil fuel gasoline. In the most positive case, it will be 10 - 15 years before prices can be expected to decrease. In contrast, with the strong development of renewable energy sources, electricity is becoming cheaper and cleaner.
According to experts, solving the problem of air pollution needs to be put in a larger picture as the challenge of climate change - the cause of pollution.
Citing studies in Europe, Dr. Filippo Giorgi pointed out that when temperatures increase, the concentration of pollutants, especially fine dust, also increases, making air quality worse. On such days, people are warned to stay indoors and limit going out.
Regarding solutions, the expert said that Hanoi needs to consider solutions to reduce the temperature in the city, such as building green buildings with more shade, planting more trees, increasing ponds, water surfaces, etc.
Like Singapore, from a country that is quite hot and there are times when people cannot work during the day outdoors, but thanks to planting many trees, the situation has changed, Dr. Filippo Giorgi cited.
VinFuture Science - Technology Week 2025 takes place from December 2 to 6 in Hanoi.
