At lunchtime today, I walked five minutes to a café across the street. While waiting at the traffic light at the Le Duan – Hai Ba Trung intersection, I stood next to several delivery drivers whose shirts were soaked with sweat.

An opinion piece recently published on VnExpress described scenes like this as a form of “cooling poverty” and proposed several remedies: A national heatwave plan, public cooling centers, and greater obligations for delivery platforms.

All of those ideas deserve serious consideration.

But looking at those drivers, I found myself thinking that the issue goes beyond the redistribution of comfort, that it is not primarily a welfare question but one of national productivity evaporating hour by hour on roads that reach 50 degrees Celsius.

Singapore rose from a poor colonial outpost to a global financial center within a single generation. The usual explanations are industrialization, public housing, education, and anti-corruption reforms. But there is another piece of the story that receives far less attention, despite Lee Kuan Yew placing it alongside those achievements.

Lee called air conditioning the greatest invention of the 20th century, and he meant it.

In a 2009 interview with New Perspectives Quarterly, he was asked what had made Singapore successful. His answer was brief and controversial: “air conditioning.”

He continued: “It changed the nature of civilization by making development possible in the tropics. The first thing I did when I became Prime Minister was to install air conditioners in public buildings. That was key to the efficiency of the public service.”

Lee was not talking about fairness. He was not proposing subsidies for low-income households. He put air conditioning at the center of government operations for a straightforward economic reason. Without it, a secretary in tropical Singapore could not type for more than a couple of hours through the humid midday heat, and an economy could not function if the public sector effectively stopped working for six hours each day.

In Lee’s view, air conditioning was productivity infrastructure, as essential as electricity and clean water.

Yet Singapore eventually became one of the most heavily air-conditioned cities in the world. According to Meteorological Service Singapore, the city-state has warmed at around twice the average global rate.

A 2024 study by the National University of Singapore’s HeatSafe project estimated that heat stress could reduce average labor productivity across industries by as much as 14% by 2035.

Construction would be hit hardest, with economic losses reaching roughly US$1.7 billion annually.

What is worth learning from Singapore is not that it installed more air conditioners. It is that it moved beyond them. Through the Cooling Singapore 2.0 program, the government has mapped urban heat across the island, expanded Green Mark building standards, imposed stricter energy-efficiency requirements, and invested heavily in district cooling systems.

The Marina Bay district cooling network alone is reported to consume 40% less energy than conventional building-by-building cooling systems.

The policy logic has remained remarkably consistent since 1959: Protect productivity through infrastructure decisions, not individual subsidies.

Vietnam is far more vulnerable than Singapore. The International Labor Organization’s report Working on a Warmer Planet places Vietnam among the tropical countries most exposed to heat stress, alongside Cambodia, Thailand, Bangladesh, and India.

Under a scenario in which global temperatures rise by 4 degrees Celsius, the ILO estimates that Vietnam could lose up to 13% of daytime working hours by the end of the century. Globally, the construction sector alone is expected to lose 19% of working hours by 2030.

These are not welfare statistics; they are competitiveness statistics.

Bangkok, Manila, Jakarta, and Kuala Lumpur all face the same challenge. The country that solves it first will have a healthier workforce, a stronger case for manufacturing investment, and a better chance of delivering major infrastructure projects on schedule.

The real question is not who suffers more on a scorching street; it is how much GDP disappears every summer and which parts of the economy suffer the biggest losses.

Motorcyclists travel in Hanoi under 40 C heat on May 25, 2026. Photo by VnExpress/The Bang

If Vietnam approached the issue the way Lee Kuan Yew did in 1959, the list of priorities will look very different.

One reason the challenge is particularly difficult in Vietnam is, in my view, the motorcycle economy.

Motorcycles are more than transportation. They shape the entire urban landscape. Because they can park on almost any sidewalk, slip through narrow alleys, and stop in front of virtually any storefront, almost every street can become a commercial corridor. Every tube house can become a shop, restaurant, workshop, or office.

This flexibility helps explain why Vietnam has one of the world’s highest rates of self-employment.

But it comes with a steep thermal cost.

Strategies for combating urban heat islands in other tropical cities generally assume the existence of buffer zones. They assume large parks, green belts separating industrial and residential areas, and spaces protected from commercial development.

During the hottest hours of the day, people can retreat to these areas. Just as important, the cooler zones lower temperatures in surrounding neighborhoods. Research in Singapore has found that the cooling effect of major parks can extend roughly 300 meters into nearby residential districts.

Hanoi and Ho Chi Minh City have largely lost meaningful buffer zones. Much of each city functions as a single heat island. Rows of tin-roofed rental rooms sit next to apartment towers. Metal workshops radiate heat through narrow gaps between buildings. Six-lane roads heated to 50 degrees Celsius run directly alongside homes and businesses.

If productivity becomes the guiding framework, three priorities stand out.

First, thermal insulation standards should become mandatory in building regulations and should apply to rental housing and privately built homes as well as commercial properties.

Second, district cooling systems should become the default option for high-density urban developments. Vietnam is in a rare position. Many of its future urban districts still exist only on planning maps. Requiring developers to evaluate district cooling for projects above a certain scale could reshape the country’s urban energy system for decades.

Third, urban greenery should be treated as climate infrastructure rather than a landscaping amenity.

Minimum green-space requirements for each ward, protected green corridors along canals, and tree buffers around industrial zones should be written into law.

When a park is sacrificed for a real-estate project, the loss is not merely recreational. Part of the city’s future productivity is being sold off.

Singapore’s experience illustrates the importance of sequencing. The city first became an air-conditioned metropolis and prospered. Only later did it discover the downside. By cooling itself so aggressively, it was also contributing to its own warming.

It is now spending heavily on heat mapping, wind corridors, district cooling, and urban greening.

Retrofitting a city is always slower and more expensive than designing it properly from the start. Vietnam still has an opportunity to avoid that path.

Instead of allowing its cities to become increasingly dependent on air conditioning and then struggling to undo the consequences, it can build climate resilience into urban planning from the outset.

That means preserving buffer zones and protecting green space. It means requiring insulation standards in new construction and designing neighborhoods that leave room for wind and shade.

The same technology can serve two very different visions of a city. The outcome depends on the choices made long before the temperature rises.

*Trinh Viet Dung holds a PhD in Marketing from Curtin University, Australia. He is currently affiliated with Kühne Logistics University Asia and serves as Vice Chairman of the Transport and Logistics Subcommittee (TLSC) under the European Chamber of Commerce in Vietnam (EuroCham).