The problem of resources supply and climate changes are recognized worldwide, despite the ratification of the Kyoto protocol. Through this protocol, each participating state is committed to reducing emissions of pollutants, most responsible for climate change. This has led to and involves the use of incentive policies towards renewable energy sources. Renewable
energy sources can produce energy without sacrificing natural resources. Hydropower currently has over other renewable sources like wind, solar and biomass, due to some key benefits
of hydropower . This generally includes a lower cost of installation to equal installed capacity, higher reliability, energy production, and more intensity and consistency over time.
Currently, hydropower technologies in the field have reached full maturity and, after almost two centuries of exploitation, the industrial use of water resources has almost reached its technical limit. In our country hydroelectric power plants have already been built and the water resources exploited and they are still in operation, thus confirming the renewability of the
resource. Recent years have witnessed the reopening of old small plants, which previously were not economically feasible. The hydropower plants can be an excellent source of economic gain also for small and medium size plants.