Brunei's economy and energy system remain built around oil and gas. In 2024, the oil and gas sector accounted for 46.7 percent of GDP, while the non-oil and gas sector made up 53.3 percent, according to the Department of Economic Planning and Statistics.
The same hydrocarbon base also shapes the country's emissions profile. Based on EDGAR emissions data compiled by the European Commission's Joint Research Centre, Brunei recorded 20.19 metric tons of CO2 per capita in 2024. This was the highest figure in ASEAN and more than double Singapore's 9.62 tons in the same year.
A new regional survey suggests Brunei's public has grown unusually alarmed about the consequences. In the State of Southeast Asia 2026 Survey by the ISEAS-Yusof Ishak Institute, 63.9 percent of Brunei respondents named climate change and extreme weather as the region's top challenge, up from 37.6 percent the year before.
The 26.3 percentage point jump was the sharpest swing recorded among all eleven economies surveyed, including newly added Timor-Leste.
An Economy Still Running on Oil and Gas
Brunei's government has pursued economic diversification for years under its Wawasan 2035 vision, and some of that effort is paying off. According to the Centre for Strategic and Policy Studies' Brunei Economic Outlook 2025, non-oil exports have risen to 70 percent of total exports, up from less than 10 percent in 2019.
The fiscal picture, however, remains closely tied to energy prices. The ASEAN+3 Macroeconomic Research Office projects that Brunei's current account surplus will fall to 11.5 percent of GDP in 2025, down from 14.6 percent in 2024, as global energy prices soften.
Over the same period, the fiscal deficit is expected to widen from 13.0 percent of GDP in FY2024 to 13.9 percent in FY2025.
The Region's Heaviest Carbon Footprint
Brunei's total greenhouse gas emissions are small in absolute terms. The country produced 15.2 megatons of CO2 equivalent in 2023, or roughly 0.03 percent of the global total, according to Climate Change Tracker.
On a per capita basis, however, the figure reaches 32.8 tons a year, a level the tracker classifies as extremely high.
Brunei's historical contribution to global warming, averaged since 1850, comes to nearly 40 tons per capita per year. The figure reflects nearly a century of oil and gas extraction, dating back to the discovery of the Seria field in 1929.
A Sharp Shift in Public Sentiment
The jump recorded in the 2026 ISEAS survey stands out against the previous year's results. In 2025, climate change was not even Brunei's top concern. Instead, 52.3 percent of Brunei respondents pointed to rising military tensions linked to potential flashpoints such as the South China Sea, while climate change registered at 37.6 percent.
The 2026 survey was conducted between January and February, following one of Southeast Asia's deadliest natural disaster episodes in years.
Tropical Cyclone Senyar and an overlapping series of storms struck the region in late November and early December 2025, leaving more than 1,600 people dead across Sri Lanka, Indonesia, Thailand, Malaysia, and Vietnam, according to the United Nations.
International disaster experts linked the unusual intensity of the storms to the broader climate crisis. The ISEAS report itself does not draw a direct connection between the disaster and Brunei's shift in sentiment.
Climate Pledges vs Current Implementation
On paper, Brunei has set ambitious targets. The Brunei Darussalam National Climate Change Policy, launched in 2020, outlines ten strategies aimed at a low-carbon, climate-resilient economy, including a goal of sourcing 30 percent of the power generation mix from renewables by 2035. Brunei has also pledged to reach net zero emissions by 2050.
Implementation has lagged behind these targets. As of 2024, fossil fuels still generated 95 percent of Brunei's electricity, according to renewable energy developer Solarvest.
The country's cumulative installed solar capacity stood at just 5 megawatts at the end of 2024, unchanged since 2021, based on figures from the International Renewable Energy Agency. A 30-megawatt solar plant is now under construction on a former landfill site in Kampong Belimbing and is expected to become operational by the end of 2026.
