Cambodia stands on the frontlines of climate change. Rising temperatures are threatening livelihoods and national development, with extreme heat events disrupting agriculture, reducing labour productivity, and deepening poverty. The country is warming faster than many of its Southeast Asian neighbours, and the consequences are visible everywhere: crops wither under scorching temperatures, outdoor workers struggle to remain productive, and energy bills climb as demand for cooling soars. If left unchecked, climate change impact including heat-related stresses could cost Cambodia nearly 10 per cent of its GDP by 2050, even if global temperature rise is kept below 2°C, according to a study in 2018 by the Ministry of Economy and Finance and National Council for Sustainable Development.

For Cambodia, cooling is no longer a question of comfort. It has become a matter of health, economic survival, and climate resilience. Recent summers have seen heat waves push temperatures above 42°C. The toll falls hardest on vulnerable groups, including children, women, the elderly and the millions who work outdoors. Hospitals and power systems are also under strain, with cooling already accounting for around 45 per cent of electricity use. Cambodia faces a stark challenge: it must find ways to protect people’s health, strengthen infrastructure resilience and deliver energy efficiency at speed and scale. 

Cambodia’s Leadership on Cooling 

Cambodia has acted decisively. In 2023, the government launched its National Cooling Action Plan (NCAP), one of the first of its kind in South-East Asia, developed with technical support from the UNEP Cool Coalition and ESCAP. As one of the first countries to leverage the Cool Coalition’s NCAP methodology, Cambodia crafted a comprehensive, multisectoral framework to tackle rising cooling demand, energy use and emissions linked to extreme heat.

These efforts strongly reflect priorities set out by the Pentagonal Strategy – Phase 1 of the Royal Government of Cambodia, focused on sustainable, inclusive and resilient development, and the Circular Strategy on Environment (2023–2028), which promotes a clean, green and sustainable development. Together, these policy frameworks strengthen Cambodia’s commitment to climate-smart growth and environmental sustainability, positioning sustainable cooling as a vital driver of resilience, energy efficiency and low-carbon development. These strategies provide a robust policy foundation for Cambodia’s leadership in advancing passive cooling and sustainable energy solutions.

The plan sets ambitious targets: cutting cooling-related emissions by 17 per cent and electricity use for cooling by 20 per cent by 2030. The country is strategically translating global cooperation into national impact by embedding cooling actions within NDC 3.0, climate adaptation strategies and socio-economic policies. This integration ensures that sustainable cooling becomes a driver of resilience, energy efficiency and low-carbon growth, setting a benchmark for other countries in South-East Asia and beyond.

From Policy to Practice

What sets Cambodia apart is its determination to move from policy to practice. Demonstration projects, such as the Borey Chankiri buildings, supported by ESCAP and UNEP within the framework of Cool Coalition, and led by Cambodia’s Ministry of Environment, are showing the potential of passive cooling strategies to lower energy demand and emissions while increasing thermal comfort in the country’s built environment. Sensors and data collection are generating hard evidence that these approaches work in Cambodia’s hot-humid climate.

Alongside these pilots, critical knowledge products have been developed including a typology analysis, a comprehensive Compendium, a passive design in Cambodian architecture contextualization study, and upcoming Passive Cooling Strategies design guidelines, which serve as practical resources for architects, engineers and builders. 

A growing Community of Practice is also enabling Cambodian professionals to exchange expertise and scale solutions nationwide. Together, these initiatives are laying the groundwork for integrating passive cooling into Cambodia’s forthcoming building code and wider development strategy. 

Cambodia’s leadership on sustainable cooling extends beyond national boundaries. At the 2023 UN Climate Change Conference (COP28), the country became signatory to the landmark Global Cooling Pledge, brought forward by the COP28 Presidency and the UNEP Cool Coalition. The Pledge commits signatory countries to reducing cooling-related emissions by 60 per cent by 2050. The commitments include deployment of passive cooling in the built environment through policy synergy and integrating into NDCs.

Cooling in NDC 3.0

Cambodia’s Third Nationally Determined Contribution (NDC 3.0) goes further still, placing sustainable cooling at the heart of its climate strategy. As the assessment conducted by Cambodia’s Ministry of Environment under the “Passive Cooling Strategies for Sustainable Development in Cambodia” project, passive cooling strategies alone are projected to deliver cumulative emission reductions of nearly 3 MtCO?e by 2035.

Beyond mitigation, the NDC also emphasizes adaptation. Policies are being developed to counter the Urban Heat Island Effect, create Heat Action Plans for cities, and protect vulnerable workers by integrating thermal comfort indices into occupational safety and health regulations. Complementary initiatives promote green building development, supported by training and certification programmes that accelerate low-carbon transformation in the construction sector. 

Lessons for the Region

Cambodia pursues a holistic model of sustainable cooling, combining policy development, evidence-informed and evidence-generating pilot projects, and capacity-building through training and knowledge-sharing. Its demonstration projects provide measurable results, creating the foundation for a long-term national program that supports local ownership. 

By integrating cooling into its ambitious yet practical NDC 3.0 targets, Cambodia is setting milestones that other countries can follow. With resources like the UNEP Cool Coalition NDC Cooling Guide, nations can identify priority actions on cooling and raise climate ambition through NDCs. Cambodia’s inclusive strategy, linking policy, practice, and community engagement, shows how sustainable cooling solutions can align with broader climate and development goals through collaboration and adaptive implementation.