Akademik Veri Yönetim Sistemi
Energy, cilt.355, 2026 (SCI-Expanded, Scopus)
This study utilises the inverted load capacity factor (ILCF), a recently developed indicator for assessing environmental sustainability, to test the inverted load capacity curve (ILCC) hypothesis, both of which were originally proposed by Dam and Sarkodie (2023). In this context, the present study analysed the impact of renewable energy R&D efficiency, fossil energy R&D inefficiency, and energy efficiency investments on the ILCF variable in Germany between 1990 and 2022. Notably, the ILCF variable is applied for the first time in the case of Germany in this study, providing new insights into the relationship between these factors and environmental sustainability. Utilising Fourier methods recently introduced in the literature, the analysis questions the ILCC hypothesis. It emphasizes that initial per capita income increases the ILCF, but after a certain threshold it decreases the ILCF, i.e. contributes to environmental sustainability. However, the ILCF hypothesis does not apply to Germany. The efficiency of R&D in renewable energy shows a significant negative impact on ILCF, emphasizing its importance in achieving sustainable outcomes. In contrast, the inefficiency of R&D in fossil energy is positively associated with ILCF, reinforcing the need to transition to cleaner energy sources. Further policy caveats are provided in the concluding section.