Hyderabad, the second-largest city in Sindh province of Pakistan, is plagued by the outdated and heavily polluting vehicles
By Prof. Dr. Mahmood Laghari
Have you ever noticed the thick, dark smoke billowing from two-stroke engine rickshaws compared to the cleaner emissions from four-stroke engine vehicles? While two-stroke engines are lightweight, simple in design, and easy to repair, they are far less efficient. The practical thermal efficiency of a two-stroke engine is only around 30%, compared to the 40% efficiency of a four-stroke engine.
Read: Two-stroke vehicles are the worst polluters
The primary reason for the excessive and toxic smoke from two-stroke engines is their design, which burns lubricant oil along with fuel. In contrast, four-stroke engines combust only fuel, resulting in cleaner emissions. When fossil fuels like petrol are burned in internal combustion engines, they release harmful pollutants such as carbon monoxide, nitrogen dioxide, unburned hydrocarbons, particulate matter, carbon dioxide, and volatile organic compounds. In the case of two-stroke engines, the combustion of lubricant oil adds even more pollutants, including unburned oil residues, metallic compounds like zinc, phosphorus, and calcium, as well as Polycyclic Aromatic Hydrocarbons (PAHs), which are known carcinogens. The result is darker, heavier smoke loaded with additional toxic substances, causing severe health issues for the public.
The Problem in Hyderabad
Hyderabad, the second-largest city in Sindh province of Pakistan, is plagued by these outdated and heavily polluting vehicles. In market areas such as Tower Market, Tilk Charrhi, Chhotaki Ghiti, Resham Gali, Haider Chowk, Naya Pull, Badin Stop, and Phuleli, two-stroke rickshaws and pickup vehicles dominate the streets. These vehicles are a major source of visible smoke pollution, which causes eye irritation, headaches, and respiratory problems after even brief exposure.
Read: Two Strokes and You’re Out
A significant contributor to this pollution is the fleet of four-seat auto-rickshaws operating between Eye Hospital and Badin Stop. Ironically, it is said that these rickshaws were initially donated by Japan in the 1960s for garbage collection in narrow streets but were repurposed for passenger transport. While the cramped seating arrangements—where men and women often sit uncomfortably close—might be a cultural quirk, the real concern is their outdated, heavily polluting engines.
A Way Forward: Cleaner Engines for a Healthier Future
To tackle this issue, it is essential to replace the two-stroke engines in these rickshaws with more efficient and environmentally friendly alternatives, such as four-stroke gasoline engines or, better yet, rechargeable electric batteries. The cost of replacing a two-stroke engine with a four-stroke one in these vintage rickshaws is currently less than 100,000 PKR per vehicle. If the poor rickshaw owners cannot bear this cost, the government should step in and subsidize the conversion.
Read: Dirty air ‘cuts South Asia life expectancy by 5 years’
This initiative would not only significantly reduce air and noise pollution in Hyderabad but also improve public health and enhance the quality of life for its residents. Cleaner engines mean cleaner air, fewer respiratory illnesses, and a healthier city overall.
A Call to Action
The government must prioritize this issue and implement a phased program to replace the engines of all two-stroke rickshaws and pickup vehicles in Hyderabad. Public health should take precedence over administrative inertia. By taking decisive action, we can ensure that the air we breathe is cleaner and safer for everyone, especially the hardworking taxpayers who deserve a better quality of life.
Read: Air pollution resulting by common mismanagement in Pakistan
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Author is a Professor and Chairman, Department of Energy and Environment, Faculty of Agricultural Engineering and Technology, Sindh Agriculture University, Tandojam.
Sir, an excellent and elaborative information regarding this long lasting and out dated engines roaming on roads in Hyderabad. All the hazards created by these old engines have correctly been pointed out. Im sharing with all seniors.