The focus of the course is to provide knowledge and understanding of the problem of sustainable and clean use of energy and the tools that are available to achieve this. The course is designed to give students a broad perspetive of the energy sources and related technologies, environmental issues, and technological challenges. This is done for fossil, renewables, and nuclear, with in-depth discussion of themes such as pollution, resource finitude, enhanced green house effect, challenges and opportunities. Tools of energy statistics are also introduced. The students get an understanding of the technology related to combustion, solar (thermal and PV), the various forms of biomass, hydropower, windpower, and nuclear. Moreover, hydrogen is also introduced as an energy carrier and player in making renewable energy more reliable as source.