Sustainable development of countries all over the world and the impact of renewable energy.

This study assesses the sustainable development of countries worldwide and the impact of renewable energy on country-level sustainability for the period 1990–2014. The nonparametric method "data envelopment analysis" is employed to measure the performance of the countries by merging environmental and economic elements into unified sustainability measures. Reflecting the different attitudes with which the countries treat environmental and economic factors in pursuing sustainability, the assessment procedure assigns priority to either economic or environmental course. We find that if economic criterion is prioritized over environmental criterion, then the developed countries significantly outperform the developing countries until early 2000s. However, the gap quickly diminishes after the period. If environmental criterion takes precedence, then developed and developing countries have similar performance over the entire horizon. Moreover, no matter which criterion is prioritized, dispersion in sustainability levels for countries in different regions has shrunk over time. Panel analysis shows that the share of renewable energy in total energy consumption has positive and strongly significant impact on sustainability, no matter whether economic prosperity or environmental protection is the priority. This implies that despite legitimate concerns about its cost efficiency, renewable energy has shown a strong positive effect in enhancing sustainability of the world. [ABSTRACT FROM AUTHOR]