As cooling needs rise, we must accelerate sustainable buildings in the tropics

The energy requirements of buildings are driven predominantly by how people use them.

By current measure, buildings account for about 39% of total annual energy-related carbon emissions.

While energy is consumed during construction, it is operational energy – powering heating, cooling, and lighting – that accounts for 80-90% of a building's total energy use over its lifecycle.

As population growth is projected to reach 10 billion by 2061, the total building stock is expected to double to meet housing and living requirements.

The highest population growth rates are expected in the tropics, which already host 40% of the global population. It is here that the largest increases in building energy demand will likely be concentrated.

Without addressing the significant emissions from buildings, this could have a devastating impact on a region that holds 80% of the world’s biodiversity.

Meanwhile, about 75% of existing buildings globally fail to meet sustainable practices.

Luckily, there are net-zero initiatives in place to support the development of healthy, sustainable built environments, balancing energy consumption with energy generated on- or off-site. These “positive-energy” buildings generate more renewable and clean energy than they consume, advancing the net-zero initiative.

While less than 1% of the global building stock has achieved net-zero status, the rising demand for indoor cooling through air conditioning in hot, humid climates creates an adjacent challenge.

Since 1990, energy use for space cooling has more than tripled, with approximately 2 billion air conditioner units now installed worldwide, accounting for as much as 50% of a building’s total operational energy in tropical regions.

Although cooling is a pressing need in these regions, the built environment still encompasses various social, financial and environmental challenges that must be addressed before accelerating global net-zero construction and to decarbonize cities and buildings.

In the meantime, there is a direct correlation between increased air conditioning use and rising temperatures and an even stronger trend with residential economic affluence.

Typically, the higher the household income, the more likely they are to install air conditioning but as technologies and utilities become more affordable, they could become more prevalent in low-income nations, eventually replacing low-carbon cooling technologies such as fans.

In particularly low-income dwellings, people may become more reliant on water, with socioeconomic inequality leading to longer, more frequent showers when air conditioning isn’t affordable or available.

Partnerships play a pivotal role in accelerating the development of net-zero buildings.

Public sector and non-profit organizations (e.g. Green Building Councils) provide clear pathways that roadmap healthy and sustainable construction, while the private sector advances cutting-edge technologies, offering more affordable and sustainable solutions that help architects and building designers meet low-energy standards.

A recent report published by the World Economic Forum’s Giving to Amplify Earth Action (GAEA) initiative, Accelerating Impact Investments for Climate and Nature in Asia, also emphasises the significant role of the philanthropic and catalytic sector.

While financial capital is often considered the primary obstacle to building a sustainable environment, the complex socioeconomic issues in regions necessitate that financial capital and solutions be strategically managed to create value.

Reducing reliance on air conditioning to address environmental concerns should not lead to social problems such as heat stress. Solutions must also be market-ready.

Since approximately 80% of today’s buildings are expected to still be standing in 2050, decarbonizing existing buildings offers a more cost-effective strategy than focusing solely on constructing new green buildings.

Asia is a region where donors direct catalytic capital towards a broader set of concerns, as more diverse issues are found there than in the rest of the world. This can offer catalytic funds to help mobilize and scale the right solutions at the right place. Philanthropies, impact investors and family offices recognise the importance of creating nature-positive and sustainable built environments.

For example, the Laudes Foundation highlights real estate as the largest global asset class ($300 trillion). They recognize both the significant carbon emissions from the built environment sector and the fact that we spend about 90% of our time indoors. Therefore, it is essential to create built environments that are both healthy and sustainable.

Led by the ClimateWorks Foundation, the Clean Cooling Collaborative (CCC) aims to transform the cooling sector by scaling sustainable cooling. Solutions include passive cooling measures and energy-efficient, climate-friendly cooling appliances.

CCC has supported various initiatives in Asia, such as deploying super-efficient ceiling fans in India and catalyzing the market for solar-reflective cool roofs, which led to over 140 square kilometres of installations across Indonesia.

The wide range of sustainable cooling solutions being scaled by CCC intends to both curb cooling-related greenhouse gas emissions and increase cooling access to enhance resilience to extreme heat.

In an overheating world, solutions that break the cycle of rising temperatures and a higher demand for cooling can also improve the quality of life for millions of people.