aspg-38-4333-1792223503 20261017075143 American Scientific Publishing Group admin@americaspg.com American Scientific Publishing Group Journal of Sustainable Development and Green Technology JSDGT 2836-5399 2026 6 2 Citra Dewi Universitas Lampung, Indonesia Realizing the carbon reduction capabilities of deploying renewable energy. is core to the constructive plan of effective climate policy in heterogenous national. contexts. Even though there is an accumulating corpus of panel econometric and machine learning. literature dealing with this relationship, methodological inconsistencies and limited geographic scope leave important empirical questions unanswered. This paper put forward a mixed analytical model combining a within-group Fixed Effects. country-clustered standard errors estimator and a Random Forest ensemble. model to measure the combined effect of renewable energy penetration, economic growth, energy consumption and reliance on fossil fuels per capita carbon. emissions. Findings affirm that the growth of renewable energy has a statistically significant impact. strong and economically significant negative impact on carbon intensity, which remains. following the elimination of country-specific unobserved heterogeneity. Economic structure and energy efficiency are shown to be co-dominant determinants, highlighting. that the energy transition is not decoupled of larger structural. transformation. Articulated income-group and regional heterogeneity issues. single-coefficient policy prescriptions, which propose decarbonization. plans have to be aligned to the national development levels. The machine learning complement validates econometric variable rankings and proves. good cross-country generalizability with country-stratified. cross-validation. 2026 09 18 4333 https://creativecommons.org/licenses/by/4.0/ 10.54216/JSDGT.060202 https://americaspg.com/journal/38/article/4333 https://americaspg.com/storage/articles/manuscripts/01M0RSZHSERRMTZP0KXH2QXDZR.pdf