Sustainable development, energy efficiency, use of renewable energy sources and protection of the environment are of greatest current interest at the start of this century. The first energy crisis in 1973 showed that conventional energy sources are limited. The knowledge that energy consumption is greatly the cause of emission of SO2, NOx and CO2 pollutants initiate worldwide investigation of technologies and production of systems using renewable energy sources representing ecologically clean energy sources with no pollutants and harmful influences. The most important role of renewable energy sources is reducing the greenhouse effect, increasing energy safety and the opportunity for opening of new work places in small and medium enterprises. In this paper a short review of alternative energy sources from the viewpoint of sustainable development, energy efficiency and protection of the environment is given including the role of the drying process technology in sustainable development through: reduction of energy “consumption”, drying source bio-fuel, solar drying, drying in order to prevent resource “losses”, drying to protect the environment etc.