Energy efficiency is of urgent consideration for the energy industry as a whole given the looming climate crisis and the transition away from fossil fuels. Although renewable energies form the new frontier for the energy sector, energy efficiency remains vital. The European Union has witnessed significant developments in energy efficiency over the past decade. Despite economic growth and technological advancements, the energy landscape in the EU presents a complex picture shaped by fluctuating consumption patterns and evolving efficiency measures. Between 2014 and 2019, the EU’s total energy supply remained relatively stable, even as GDP grew by an average of 2.2% per year. This stability in energy supply, amidst economic expansion, reflects a notable decoupling of economic growth from energy consumption. However, the COVID-19 pandemic in 2020 brought a dramatic shift, with both GDP and total energy supply dropping by over 6%. This disruption halted the declining trend in primary energy intensity, which had been decreasing at a rate of 2% per year from 2014 to 2019. The dynamics of final energy consumption provide further insights. From 2014 to 2019, final consumption increased by 0.7% annually. The transport sector experienced the highest growth at 1.4% per year, while industry consumption grew by a modest 0.3% annually. The pandemic caused a significant reduction in final consumption by 5.6% in 2020, with the transport sector experiencing an 11% decline due to lockdowns and travel restrictions. Interestingly, household consumption rose by 1.4% as people spent more time at home, while the services sector recorded a substantial 7% drop in electricity consumption due to teleworking and the temporary closure of many establishments. Energy efficiency improvements have nonetheless resulted in considerable savings. In 2019, the EU saved an estimated 196 million tonnes of oil equivalent (Mtoe) compared to 2000, representing a 21% reduction in final energy consumption.