We can see a steady growing of popularity towards renewable energy sources. The two main arguments for this type of energy are their significant cost-reducing ability and the importance of environmental awareness. I ascertained the environmental effect and the price of using renewable energy. I investigated the life-cycle of 6 different devices, and compared their environmental effects. The investigated devices were: solar cell, wind turbine, biogas engine, solar collector, Stirling-engine, water turbine. I inquired the working mechanisms of these machines. I divided the life cycle into 4 parts: manufacturing, installing, operating, disassembling. I mainly investigated the amount of pollutants which are generated during their working. For this goal I had to learn about producing method of iron, steel, aluminium, copper and glass. I estimated the produced electrical and heat energy, and calculated the nascent dust, CO and CO2 to each produced MWh. I investigated the installing rules of micro-powerplants under 80 MW. I analyzed the energy storing methods and the power controlling systems of every device. I compared the results, and highlighted the advantages and disadvantages of using such equipments. In the end of the project I compared the renewable sources to the atomic powerplants, and made the conclusion about the expediency of the powerplants under 80 MW powered by renewable energy sources.