Renewable Energy - Hydro

Hydro energy is energy harnessed and used from large water resources like rivers, lakes and even ocean. Since water is about 800 times denser than air, even a slow flowing stream of water, or moderate sea swell, can yield considerable amounts of energy. It is a cheap, reliable and non-polluting source of energy. There are many forms of water energy technologies depending on their capacity and designs:-

1) Hydroelectric is a term usually referred to generation of electricity by hydroelectric dams. Hydroelectric dams use the gravitational force of falling or flowing water (collected by the dam) to produce electrical power through the turbines. It is the most widely used form of renewable energy.

2) Micro hydro systems (or also known as mini-hydro) are hydroelectric power installations that typically produce up to 100 kW of power. They are often used in water rich areas as a remote-area power supply and usually stand alone power systems. Unlike the hydroelectric, this mini-hydro does not need dam to create falling or flowing water but converting the flow of water (like rivers) into electrical energy.

3) Run-of-the-river (ROR) hydroelectricity systems are a type of hydroelectric generation whereby a considerably smaller water storage called pondage is used to supply a power station but some ROR system doesn’t use pondage. The ROR systems derive kinetic energy from rivers and oceans without using a dam.

Hydro energy is the oldest and most exploited renewable energy in Malaysia, so this type of renewable energy is already have a good reputation and contribute 5% (in 2008) of total Malaysian power grid. The Bakum dam in Sarawak, one of the largest dams in South-East Asia, is expected to finally complete by 2010 with a capacity of 2400 MW. But hydroelectric have the most impact on the environment than all other renewable energies, ecosystem damage, loss of land and siltation due to the dam. For this project, a micro hydro system is suitable approach for the usage of hydro power.

Micro hydro systems are hydroelectric power installations that typically produce up to 100 kW of power. They are often used in water rich areas as a remote-area power supply and usually stand alone power systems. All hydro power plants have similar operation in generating electricity which is flow in water from water source to turn the turbine and generating electricity. Unlike the hydroelectric, this mini-hydro does not need dam to create falling or flowing water but converting the flow of water (like rivers) into electrical energy. So, this type of hydro power system has very little impact to the environment, unlike their hydroelectric dam cousin.

Typical Mini Hydro Diagram

Micro hydro systems are the complement photovoltaic solar energy systems because in many areas, the water flow (and thus available hydro power) is highest in the winter when solar energy is at a minimum. Micro hydro is frequently accomplished with a pelton wheel for high head, low flow water supply. The installation is often just a small dammed pool, at the top of a waterfall, with several hundred feet of pipe leading to a small generator housing.