Impact of Clean Energy Integration on CO2 Intensity in European Power Systems

This paper examines the impact of clean energy integration on CO2 intensity in European power systems over 2015–2024, based on a dataset of 38 European countries. The study applies three analyses: (i) descriptive statistics on cross-country patterns (ii) fixed-effects regression on clean energy and CO2 intensity, and (iii) crisis-period modelling for 2021–2022. The descriptive results reveal significant heterogeneity. The average clean energy share is 30.8%, ranging from below 5% (Malta, Moldova) to above 45% (France) and approximately 38% (Sweden). Accordingly, CO2 intensity varies between 23.6 gCO2 /kWh (Sweden) and 982 gCO2 /kWh (Kosovo), indicating different decarbonization rates across Europe. Regression analysis provides statistically significant evidence that clean energy is associated with lower carbon intensity. A one-point increase in the share of wind and solar power corresponds to a reduction of 12.18 gCO2 /kWh (p < 0.01), while a similar increase in other clean sources (hydroelectric, nuclear) corresponds to a decrease of 12.24 gCO2 /kWh (p < 0.01). Electricity demand has no statistically significant relationship with CO2intensity. Crisis-era modeling shows insignificant interaction terms for 2021-2022, suggesting stability of the relationships during the crisis. Overall, the findings support the importance of clean energy integration, highlight persistent inequalities across countries, and the value of policy resilience during major energy shocks.