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Historical Energy Security Analysis of EU Countries

A secure energy supply is important for all countries. This is especially true for EU countries for geopolitical reasons and because of ongoing reforms in energy markets. This study aims to understand how the energy security of EU countries has evolved by applying three energy security indicators with time-series clustering approaches. Overall, energy security improved between 1978 and 2014, with Denmark and the Czech Republic presenting the greatest improvements. The main driver of improvement is the diversification of primary energy. Factors relating to imports are also significant. Cluster analysis identified three country groups: those with high energy security and moderate improvements; those with lower energy security and moderate improvements; and those with initially low energy security followed by significant improvements. The first and third groups are of particular interest. The former defines best practices, whereas the policies of the latter leading to improvement can serve as a guide for others.