The energy intensity of a country shows how much energy is needed to produce a single euro of gross domestic product (GDP). Central-Europe, which is more industry-oriented and has been addicted to cheap Soviet natural gas needs a lot more energy to produce its lower national income than Western Europe. This partly explains the worries and the political economy of energy-related issues in the region.

Darker shades mean more energy needed to produce a single euro of GDP. You can further analyze the dataset on Many Eyes here. A lot of electricity in Central Europe is imported from Ukraine and almost all natural gas from Russia.