Tonga Transport and Climate Profile 2026

Outline

TONGA

TRANSPORT AND CLIMATE PROFILE

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Background

Tonga, a Pacific Island country classified as an upper-middle-income economy, faces a complex balance between economic growth and environmental sustainability. With a 2024 population of 104,000 and a GDP (PPP) of $821.4 million, the nation has a GDP per capita of $7,885. Although its economy is relatively small, the transport sector is a major contributor to national Greenhouse Gas (GHG) emissions. In 2024, this sector emitted 83 thousand tonnes of GHGs, representing about 28% of all emissions across Tonga's economy. Worryingly, the rate of emissions growth has sped up; while transport-related CO2 emissions grew at an annual rate of 2.7% before the Paris Agreement, this rate increased to 3.7% per year post-2015.

The emissions profile is dominated by road transport, which accounts for 86% of total transport emissions and nearly a quarter (24%) of the entire economy's carbon footprint. In contrast, domestic navigation and aviation each contribute 7%, while rail remains non-existent. Although Tonga's transport CO2 intensity relative to GDP has declined marginally—from 102.9 gCO2e/USD in 2015 to 100.9 in 2024—it remains significantly higher than the Asia-Pacific average (29.0) and the Pacific Islands subregional average (56.6). This suggests a critical need for structural decoupling of transport activity from carbon output.

Tonga's transport energy sector relies entirely on fossil fuels. In 2023, all of the 1,366 terajoules of energy used was from oil, a figure unchanged since 2010. Although energy consumption growth has slowed from 8% annually (2000–2010) to 2% since 2010, energy intensity relative to GDP has increased consistently, reaching 1.66 MJ/USD in 2023. This is higher than the Asia-Pacific (0.37) and Pacific Islands (0.74) averages, indicating inefficiencies. Road transport makes up 83% of energy use, with domestic navigation at 15%. Notably, biofuels and electricity have not yet entered the transport mix, revealing a significant gap in alternative energy adoption. Additionally, subsidies for fossil fuels generate external costs, mainly through road crashes (43%), congestion (49%), and road damage (7%).

As a Pacific nation, Tonga is exceptionally vulnerable to climate-induced disruptions and natural hazards. Since 2000, the country has recorded 12 major natural disasters—predominantly storms (75%) and earthquakes (8%)—which have affected 225,000 people and resulted in economic costs exceeding $399,275. The transport sector faces a potential average annual loss (AAL) of $530.7 thousand due to infrastructure damage, representing 0.065% of national GDP. These losses are primarily concentrated in road infrastructure (61%) and ports (30%). Tonga's systemic risk is further highlighted by its 175th-place ranking in National Road Vulnerability, indicating a high risk of network failure during disasters. Moreover, the existential threat of sea-level rise looms large, with 27% of the population residing in low-elevation coastal zones. Despite these risks, only 31% of current policy measures incorporate climate adaptation or resilience components.

Motorization in Tonga has increased from 325 vehicles per thousand population in 2000 to 491 in 2024, far exceeding the Asia-Pacific average of 317. The current fleet is composed largely of two-wheelers (52%) and light-duty vehicles (LDVs) (33%), while trucks account for 14%. While bus imports doubled in value between the 2010–2015 and 2015–2024 periods (reaching $7.5 million), none of these imports were electric. The electric vehicle (EV) market remains in its infancy; though $258 thousand worth of EVs were imported between 2017 and 2024, they represented <1% of total road vehicle imports in 2024. The UNEP E-mobility Readiness Index reflects this nascent stage, giving Tonga a score of 58/100, with particularly low marks in technology and market readiness (5) and financial instruments (13). On a positive note, bicycle imports totaled $1.4 million between 2015 and 2024, suggesting a foundation for active mobility.

The financing of Tonga's transport sector has relied heavily on Official Development Assistance (ODA), which increased from $29.8 million (2002–2010) to $117.3 million (2011–2023). A strategic shift in ODA allocation is evident, with funding moving away from ports (80% to 57%) toward airports (6% to 35%), while road funding halved to 7%. Notably, there has been no recorded public-private partnership (PPP) investment in the sector since 2000.

Policy-wise, the NDC 3.0 (2025) aims for a 13% reduction in GHG emissions by 2030 compared to 2006, focusing on renewable energy and efficiency improvements. Transport-specific goals target a reduction of 26 GgCO2e by 2030 and 45 GgCO2e by 2035. The 2021-2050 Low Emission Development Strategy (LEDS) addresses electric vehicle mandates and procurement initiatives, but Tonga does not currently have a formal net-zero or carbon-neutrality target in its main NDC and LTS documents. Focused policies emphasize renewable energy, vehicle efficiency, and alternative fuels; however, existing NDCs and LTSs cover only 21% of the ten most relevant measure types. Other key planning documents include the Tonga Climate Resilient Transport project and the Energy Efficiency Master Plan, both crucial for integrating sectoral development with climate goals imperatives.

Avoid: To reduce the necessity of motorized travel, Tonga is prioritizing integrated urban planning and the decentralization of services. The National Spatial Planning and Management Act 2012 provides the statutory framework for developing an urban structure that ensures equitable access to employment and services, thereby minimizing travel distances. Complementary to this, the Low Emission Development Strategy 2021-2050 advocates for the expansion of digital services and internet connectivity to facilitate telecommuting and decentralized work locations. These demand-side measures are further reinforced by the Energy Efficiency Master Plan, which targets a 20% reduction in vehicle kilometers traveled (VKT) for light-duty vehicles through a combination of walking, transit, and ridesharing initiatives.

Shift: Moving towards more sustainable transportation involves investing heavily in non-motorized infrastructure and upgrading public transit systems. The Tonga Climate Resilient Transport project includes a plan for road traffic modeling in Nuku'alofa to incorporate cycleways and pedestrian access. The Low Emission Development Strategy 2021-2050 outlines initiatives like establishing "pedestrians-only" city centers and developing green pathways to promote active transportation. Additionally, the Energy Efficiency Master Plan aims to improve public transport by coordinating taxi services via mobile apps and encouraging "last-mile" solutions, such as solar-powered tuk-tuks, as noted in the Third National Communication on Climate Change Report.

Improve: Technical efficiency and fuel switching constitute the final pillar of Tonga's strategy, with a strong focus on electrification and strict regulatory standards. Tonga's 2020 Second Nationally Determined Contribution (NDC) aims for 70% renewable electricity by 2030, supporting the Energy Efficiency Master Plan's target of having 10% of new light-duty vehicles electric by that year. Reforms introduced by the Traffic Act 2020 and the Roads Act 2020 facilitate the enforcement of maximum weight limits and vehicle inspections, ensuring fleet integrity. In the maritime and aviation sectors, Tonga's State Action Plan on CO2 Emissions Reduction from International Aviation and the Tonga NDC 3.0 detail initiatives to transition to cleaner ground support equipment and improve ship efficiency, including pilot projects for biodiesel blending and solar-wind hybrid cargo designs.