Hydroelectric Power

Publisher Summary The global water cycle, driven by the sun, is the renewable resource for hydropower. On a global scale, hydropower has important advantages over most other electricity generation technologies. Hydropower is renewable, reliable, clean, and largely carbon-free, and represents a flexible peak-load technology. Basically, water's potential (or kinetic) energy is converted into electricity using water turbines and electric generators. Globally, between 40 000 and 50 000 large dams have been built for irrigation, domestic water use, flood control, and power generation. With new technologies available, resources can be more fully utilized and, with changing demands, hydropower has become important for storing energy rather than making energy available. Hydropower schemes are strongly site specific. As a consequence, many important economic and environmental aspects of hydropower schemes vary widely, i.e. technical variables, specific investment costs, total production costs, peak load production possibilities, and external effects. In contrast to other electricity producing technologies, dealing with hydropower on a technological level is a challenging task. The strong heterogeneity of hydropower schemes complicates the adequate definition and characterization of hydropower. Liberalization of electricity markets and government policies which encourage sustainable technologies challenge hydropower, on the one hand, to be competitive and, on the other, to show that it is environmentally and socially benign compared to other electricity-producing technologies. Sustainability must become the benchmark for all future hydropower schemes.