Book excerpt: The 3rd International Congress on Energy Efficiency and Energy Related Materials (ENEFM2015) was held from 19–23 October 2015. This congress focused on the latest developments of sustainable energy technologies, materials for sustainable energy applications and environmental and economic perspectives of energy. These proceedings included 40 peer-reviewed technical papers, submitted by leading academic and research institutions from over 23 countries and represented some of the most cutting-edge researches available. The sections included in the 40 papers are listed as follows: Solar Energy, Fuel cells, Hydrogen productions, Hydrogen storage, Energy storage, Energy saving, Biofuels and Bioenergy, Wind Energy, Nuclear Energy, Fossil Energy, Hydropower, Carbon capture and storage, Materials for renewable energy storage and conversion, Photovoltaics and solar cells, Fuel generation from renewables (catalysis), Carbon dioxide sequestration and conversion, Materials for energy saving, Thermoelectrics, Energy saving in buildings, Bio-Assessment and Toxicology, Air pollution from mobile and stationary sources, Transport of Air Pollutants, Environment-Friendly Construction and Development, Energy Management Systems.