Greenhouse gas emissions (GHG) refer to gases polluting the environment, such as CO2 and methane. Around 10% of the GHG emitted worldwide in 2012 came from the EU. However, in 2014, greenhouse gas emissions in the EU-28 were down by 22.9 % compared with 1990 levels, representing a significant reduction, putting the EU on track to surpass its 2020 climate and energy package targets, which is to reduce GHG emissions by 20 % by 2020 and by 40 % by 2030 compared with 1990 [1]. Moreover, a surge in the use of Renewable energy sources (RES) helped Europe to cut its fossil fuels consumption and greenhouse gas emissions by about 10% in 2015 [2].
Electricity and Heat Production (25% of 2010 global greenhouse gas emissions): The burning of coal, natural gas, and oil for electricity and heat is the largest single source of global greenhouse gas emissions. Industry (21% of 2010 global greenhouse gas emissions): Greenhouse gas emissions from industry primarily involve fossil fuels burned on site at facilities for energy. This sector also includes emissions from chemical, metallurgical, and mineral transformation processes not associated with energy consumption and emissions from waste management activities [3].