Hydro energy is an important source of energy and widely
popular alternative to fossil fuel in generating electricity when
compared to other types of energy. Data on world electricity
generation, classified by types of fuel, as seen in Fig. 1, show that
a total amount of 22,126 TWh of electricity was generated in 2011
[6]. The figure also shows that 15.8% of this amount came from
hydro energy, whereas electricity from other types of alternative
energy contributed only 4.5% of the total world electricity supply.
In other words, electricity supply generated from hydro energy
amounted to 78% of all of the electricity supply generated by
alternative energy.
Table 2 shows the technical potential, status of electricity
generation, and installed capacity of hydro energy in each region
of the world in 2009. The worldwide technical potential of hydropowered
electricity generation was 14,576 TWh per year, whereas
the technical potential of installed capacity was 3721 GW, or four
times the capacity at the time. Asia had the highest generation
potential at 53% of worldwide potential. Nevertheless, Asia generated
only 20% of the installed capacity. In other words, about 80%
of water resources in Asia were not utilized for electricity generation.
Europe had the ability to generate electricity from hydro
power as the region had 53% of technical potential. In contrast,
Africa had the ability to generate only 8% of its potential. The