Yeşil ve Fosil Enerji Girdileri İçin Yönlendirilmiş Teknik Değişimin Geçerliliğinin Test Edilmesi, Almanya Örneği

In this study, the validity of directed technical change in Germany over the period 1995–2020 is tested. In the analysis—where nested CES functions are employed—two separate models are constructed to examine the capital–labor and energy–renewable energy groups as a two-tier structure. In both models, returns to scale are assumed to be approximately unitary. In the first model, the capital–labor and energy–renewable groups carry equal weight at the lower tier, whereas, at the upper tier, the dominance of the capital–labor group is clearly observed; in the second model, however, the energy group is found to have the larger weight. Although a strong substitution potential is detected among energy forms, the substitution elasticity between capital and labor fails to achieve statistical significance in both the first and the second model. The substitution capability between the two subgroups is also found to be weak. The R² values in both estimation sets are high, confirming the overall goodness of fit.