The Asia Zero Emissions Community has taken a collaborative approach to energy transition with the triadic aims: carbon neutrality, economic growth, and energy security. The key is to find and maintain the balance between pursuing the three goals without jeopardizing one another. Aligned with the Paris Agreement’s principle of 'common but differentiated responsibilities and respective capabilities', the AZEC incorporates the concept of various pathways to advance energy transition. Tailoring transition strategies to suit specific individual energy contexts of each AZEC partner countries is of paramount importance. The cooperation is multifaceted ranging from facilitating policy coordination, providing financial, technological, and human resources support to enhancing joint cooperation on decarbonisation efforts. The signing of memorandums of understanding (MOUs) regarding policy coordination at the ministerial level have paved ways for numerous public private investment MOUs, in which the cooperation has been tailored to specific energy mix and contexts of each AZEC partner countries. These MOUs include collaborations in terms of 1) financial support on energy infrastructure support programs, 2) technical support on cost-competitive commercialization of advance energy technology and feasibility assessment, 3) energy governance focusing on ESG advice and alliance, and 4) joint research, business matching and joint investment, etc. Through AZEC platform, Japan shares technologies and experiences with ASEAN countries and these collaborative projects differ on a case-by-case basis, echoing the 'tailoring' and 'various pathways' AZEC principle.

Complex geopolitical landscape in the region marked by tensions between major global powers and ASEAN's effort to maintain neutrality while striving to maintain its strategic relevance and deepen collaborations with various trade and economic partners could, at a certain extent, influence Japan-ASEAN cooperation on energy transition. As Japan and ASEAN vow to widen cooperation in celebration of our 50 years of friendship, cooperation on the transition towards decarbonising energy system against the backdrop of China's growing influence and geopolitical tensions in the South China Sea could be characterized by strategic competition. However, focusing on energy transition cooperation, even though China has also played a vital role in promoting collaborative efforts and multilateral agreements on regional energy transition (especially through Regional Comprehensive Economic Partnership (RCEP)), I do not think any rivalry among major regional powers would highly hinder ASEAN energy transition, as long as the cooperation occurs within a broader framework of collective strategic interests of supply chain resilience and regional stability. Energy transition from fossil fuels to more sustainable renewable energy sources requires coordinated efforts across various fronts.

Diverse energy contexts and economic landscapes. First, even though ASEAN's energy landscape is dominated by fossil fuels, which poses a significant challenge to achieving carbon neutrality, the energy mixes across ASEAN is quite diverse. For instance, Brunei Darussalam, Indonesia, and Malaysia have relatively significant reserves of crude oil and natural gas, making fossil fuels a substantial part of their energy mix. On the other hand, Laos focuses on hydroelectric power and the Philippines has invested in geothermal energy whereas urban-rural disparities in access to electricity are still prominent in Cambodia and Myanmar. Singapore, lacking in natural resources, is a regional energy hub and heavily dependent on energy imports. Due to diverse energy contexts, ASEAN countries perceived energy security differently and have differing priorities and capacities for addressing environmental and climate issues—not to mention energy infrastructure requirements. Second, ASEAN countries span a wide range of economic development stages. Singapore, for instance, is a highly developed, global financial hub, while countries like Cambodia, Laos, and Myanmar are among the least developed in the region. In addition, economic growth usually correlates to rising demand for energy. Therefore, ASEAN's energy demand is expected to continue growing and, with the current energy mixes—it means increasing reliance on fossil fuels. To address these challenges, the region would need a considerable increase in energy investment, advanced renewable energy, and low emissions technology as well as regional collaboration and policy coordination to facilitate the transition.

Regarding approaches to achieving decarbonisation, both Japan and ASEAN are determined to decipher effective transition strategies and policies that could be implemented without discouraging economic growth and energy security. This is where Japan and ASEAN can learn from each other. Japan's sectoral transition strategies and decentralising transition governance could be used as referent policy guidelines for ASEAN countries in terms of localising policy adaptation, management, and monitoring. Additionally, ASEAN countries could also learn and benefit from Japan's expertise and technology transfer to accelerate decarbonisation efforts. On the other hand, ASEAN, with its diverse geographic conditions and energy contexts, would be able to reflect different decarbonisation challenges that requires differed application of innovative decarbonisation technologies and various adaptation strategies. Japan could, thus, learn from these diverse applications, especially in the context of deploying renewable energy technologies in varied geographical settings to improve its own resilience. Joint projects and collaboration on research and development in renewable energy technologies, smart grids, and energy storage solutions would be beneficial to both Japan and ASEAN countries to accelerate innovation and cost competitiveness.

The first thing would be increasing investment in advanced renewable energy and decarbonisation technologies. Japan’s technological expertise and capital could help accelerate the adoption of these technologies in ASEAN countries, which may have considerable renewable energy potential but still underdeveloped in terms of infrastructure. As ASEAN countries work towards Nationally Determined Contributions (NDCs) under the Paris Agreement, cooperation with Japan could also involve policy support and coordination e.g., assistance in developing regulatory frameworks for renewable energy, creating incentives for clean energy investment, and harmonizing standards and practices across the region. In addition, another possible cooperation would promote a more collective enhancement of energy security through regional energy connectivity (by integrating gas markets in the region, for example) in order to make energy systems more resilient to external shocks. Lastly, Japan-ASEAN cooperation on energy transition could focus more on strategic directions to foster a partnership that would not only accelerate the transition to carbon neutrality, economic growth, and energy security but would also enhance long-term approaches to environmental sustainability. Admittedly, decarbonisation technologies that both Japan and ASEAN are currently pursuing are yet to replace the use of fossil fuels. Future cooperation could address such concern and gradually work towards the mutual goal.