**5. Conclusions and Policy Implications**

ASEAN's energy transition will largely depend on increasing the share of renewables and clean fuels such as hydrogen and the clean use of fossil fuel to create a clean energy future. Fossil fuel (coal, oil, and gas) accounted for almost 80% of ASEAN's energy mix in 2017, a share that is expected to rise to 82% in BAU. Transitioning from a fossil fuel–based energy system to a clean energy system requires drastic policy changes to encourage embracing renewables and clean fuels whilst accelerating the use of clean technologies in employing fossil fuel (coal, oil, and natural gas). The study used energy modelling scenarios to explore policy options to abate emissions in ASEAN by giving wind and solar energy a high share of the energy mix and using electricity curtailment to promote renewable hydrogen production. The findings found that ASEAN has high potential to produce renewable hydrogen using curtailed electricity. The higher share of renewables under various policy scenarios will see a large reduction in CO2 emissions, which could lead to decarbonizing emissions and contribute to abating global climate change. The potential emission abatement ranges from −340 Mt-C in APS to −648 Mt-C, −710 Mt-C, and −774 Mt-C in Scenario1, Scenario2, and Scenario3, respectively. Emissions will be cut by 28% from BAU to APS, 53% from BAU to Scenario1, 58% from BAU to Scenario2, and 64% from BAU to Scenario3.

The results of the study imply policy implications for ASEAN's energy policy reforms to ensure that clean fuels such as hydrogen and renewables and clean technologies will have a big role to play to decarbonize ASEAN's emissions. The below policy implications are derived from this study for the hydrogen adoption in ASEAN:


and private companies. Financing mechanisms such as banks must create favorable conditions to finance facilities such as electrolyzers. Governments must provide financial incentives to invest in developing hydrogen.


**Author Contributions:** Conceptualization, F.K. and J.A.; methodology, H.P.; software, H.P.; validation, H.P., F.K. and J.A.; formal analysis, H.P.; investigation, H.P.; resources, H.P.; data curation, H.P.; writing—original draft preparation, H.P.; writing—review and editing, H.P.; visualization, H.P.; supervision, H.P.; project administration, H.P.; funding acquisition, H.P. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Conflicts of Interest:** The authors declare no conflict of interest.
