Hierarchical modeling of the 50 largest economies to verify the impact of GDP, population and renewable energy generation in CO2 emissions

The use of fossil fuels for electricity generation is primarily responsible for global greenhouse gas emissions. The increase in carbon dioxide (CO2) emissions in recent years is believed to have been driven by economic and population growth. Consequently, many countries have been looking for ways to reduce their pollution. This study aims to verify the impact of Gross Domestic Product (GDP), population growth and the generation of renewable energies on CO2 emissions in the 50 largest world economies over the years 1990-2015. To do so, a hierarchical regression modeling was performed, considering "country" as the most comprehensive level and "year" as the most specific one. The results confirmed the positive impact of GDP and population on CO2 emissions and renewable energy generation as a way to reduce emissions. China and Denmark stood out in the analysis. The former has become the largest emitter of CO2 on the planet, while the latter has increased its share of renewable energy in its electrical matrix by more than twenty times and displayed a tendency to reduce CO2 emissions. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.