The primary energy consumption in the world is dominated by fossil fuels and is constantly rising. From 1990 to 2015 the total increase was by more than one-and-a-half. With 6.8%, hydroelectricity covered the largest share of clean energy consumption in 2015. The primary energy consumption coming from nuclear energy stayed more or less constant over the last decades when measured in millions of oil equivalent, meaning that the percentage declined to 4.4% in 2015. Renewable energies, however, have been significantly increasing their share, reaching 2.8% in 2015. This means that the share of primary energy demand met with sources with low carbon emissions was 14%.