The hydrologic cycle refers to the following
process. Firstly, the sun heats water about 97 percent from oceans water
evaporates. Then, rising air currents transport water vapour to the upper
atmosphere where lower temperatures condense vapour into clouds. Air currents
move the clouds around the globe and eventually, waterfalls as precipitation.
Through this process, water can reach altitudes higher than sea level 10.
Gravity causes water to descend from higher
elevations creating opportunities to harness water energy-gravitational energy
from falling water and kinetic energy from flowing water. The amount of kinetic
energy available from water flow depends on the height from which the water
drops, the angle of the slope, and the volume of water per unit of time, in
example, the discharge. The energy of flowing water is harnessed by turbines,
which are placed in the path of the water flow. The force exerted by water
moving over turbine blades rotates the turbine runner; the turbine runner
rotates the generator, which produces electricity 10.
Thus the operational of the water cycle describe the principle of working
about hydropower. In order to generate electricity the water level and water
flow should be considered to get the current amount of voltage.
The theoretical power available at a
given hydropower can be calculated using the equation below. The head and flow
rate must be determined so appropriated hydropower can be selected properly.
The hydraulic powers that need to convert to useful power will be based on the
efficiency of the component comprise of the installation.
P= Power, W
p= Density of working
g= Acceleration due to
2.3 HYDROPOWER POTENTIAL
There is a big potential for small hydropower projects to
grow in Malaysia, as it provides about 500 MW total generating capacity for the
long run, especially in the run-of-river types. Normally, small hydropower
systems are run-of-river schemes, in which large storage reservoirs is not
required. Furthermore, this type of power generation is considered to be one of
the oldest environmentally friendly technologies as the run-of-river plants do
not emit any CO2. Malaysia’s installed electricity generating
capacity was 26,063 MW in 2013, consisting of 21,628 MW in Peninsular Malaysia,
1,303 MW in Sabah and 3,132 MW in Sarawak 12. Gas and coal remained the
most-used fuels for power generation at 47.99% and 25.73%, respectively,
followed by hydroelectric at 14.73% and biomass at 2.97%. Meanwhile, mini hydro
contributed 0.17%. In terms of electricity growth, maximum demand of 16,562 MW
as recorded on May 13, 2013, surpassing the initial target of 16,324 MW by 1.5%