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What are the benefits of having the system in Malaysia?
One of the benefits of the hydroelectric system is that when the
dam is completed it cangenerate electricity at constant rate.
The other benefit is water from the hydroelectric power plant
free from contaminationand can be used to irrigation purpose.
This system also able to control the amount of energy produced.
When the energydemand is high control get can be open and the
energy is low control get can be shut.
This show the effectiveness hydroelectric system in terms of
using water.
When in use, electricity produced by hydroelectric systems does
not produce green housegases. They do not pollute the
atmosphere.
The lake that forms behind the dam can be used for water sports
and leisure / pleasureactivities. Often large dams become tourist
attractions in their own right.
What are the economics and environment impacts of the renewable
energy to the electricity
consumer?
Dams consistently cost more and take longer to build than
projected. In general, thelarger a hydro project is, the larger its
construction cost overrun in percentage terms.
In too many cases, the burden of uneconomic dams is shouldered
by a nation's citizens,while the project builders walk away with a
tidy profit and another project to add to their
portfolio. Given that most of the world's large dams are now
being built in the world's
poorest nations, this is a burden they can ill afford.
Another issue is that large dams are often the largest energy
development in many poorcountries, which can lead to an unbalanced
energy supply. While countries generally get
richer as they increase their use of modern energy, the trend
goes the other way for
dependency on hydroelectricity.
The dam wall itself blocks fish migrations, which in some cases
and with some speciescompletely separate spawning habitats from
rearing habitats. The dam also traps
sediments, which are critical for maintaining physical processes
and habitats downstream
of the dam.
Another significant and obvious impact is the transformation
upstream of the dam from afree-flowing river ecosystem to an
artificial slack-water reservoir habitat. Changes in
temperature, chemical composition, dissolved oxygen levels and
the physical properties
of a reservoir are often not suitable to the aquatic plants and
animals that evolved with a
given river system.
The alteration of a river's flow and sediment transport
downstream of a dam often causesthe greatest sustained
environmental impacts. Life in and around a river evolves and
is
conditioned on the timing and quantities of river flow.
Disrupted and altered water flows
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can be as severe as completely de-watering river reaches and the
life they contain. Yet
even subtle changes in the quantity and timing of water flows
impact aquatic and riparian
life, which can unravel the ecological web of a river
system.
A dam also holds backsediments that would naturally replenish
downstream ecosystems.When a river is deprived of its sediment
load, it seeks to recapture it by eroding the
downstream river bed and banks. Riverbeds downstream of dams are
typically eroded by
several meters within the decade of first closing a dam; the
damage can extend for tens or
even hundreds of kilometers below a dam.
Riverbed deepening will also lower groundwater tables along a
river, lowering the watertable accessible to plant roots. Altering
the riverbed also reduces habitat for fish that
spawn in river bottoms, and for invertebrates.
1. http://www.technologystudent.com/energy1/hydr2.htm2.
http://www.internationalrivers.org/economic-impacts-of-dams3.
http://www.internationalrivers.org/node/2221http://www.technologystudent.com/energy1/hydr2.htmhttp://www.technologystudent.com/energy1/hydr2.htmhttp://www.internationalrivers.org/economic-impacts-of-damshttp://www.internationalrivers.org/economic-impacts-of-damshttp://www.internationalrivers.org/economic-impacts-of-damshttp://www.technologystudent.com/energy1/hydr2.htmhttp://www.internationalrivers.org/node/2221
