1. Combating global
warming
Hydroelectric power
By Leanne Jones and
Gemma Mansell 9C of
Denbigh high school
2. What is HEP
HEP (Hydroelectric Power) is an
environmentally friendly way to generate
electricity.
3. How it works
A dam is built to trap water, usually in a valley
where there is an existing lake.Water is
allowed to flow through tunnels into the
dam,to turn turbines and thus drive
generators.Notice that the dam is much
thicker at the bottom than at the top,because
the pressure of the water increases with
depth.
5. Where is the best place for a HEP
station?
The best place for a hydro-electric power
station is up in the mountains.This is
because it doesn’t get too hot so the water
doesn’t evaporate and stays in the
dam.Also there is a lot of rain in the
mountains ensuring the reservoir is always
full.The land also needs to be impermeable
so that the water doesn’t infiltrate through
the rocks below.
6. Advantages of HEP
Once the dam is
built,the energy is No waste or pollution
virtually free produced
Water can be stored Electricity can be
above the dam ready generated constantly
to cope with peaks in Hydro-electric power
demand
stations can increase
much more reliable to full power very
than wind,solar or
quickly unlike other
wave power
power stations
7. Disadvantages of HEP
The dams are very Finding a suitable site can
expensive to be difficult - the impact on
build,however many residents and the
dams are also used for environment may be
flood control or
irrigation,so building costs unacceptable.
can be shared
Building a large dam will Water quality and
flood a very large area quantity downstream can
upstream,causing be affected, which can
problems for animals that have an impact on plant
used to live there life.
8. Is it renewable?
Hydro-electric power is renewable.The
Sun provides the water by evaporation
from the sea,and will keep on doing so
The Sun evaporates water
from the sea and lakes,
which forms clouds and falls
as rain in the mountains,
keeping the dam supplied
with water.
9. Glen Lyn Gorge
Glen Lyn Gorge is in Lynmouth in north
Devon, and is a 300kW hydro scheme
“buried” in the side of Glen Lyn Gorge
which is located in the centre of Lynmouth
village, where two rivers, the East and
West Lyn, converge. The scheme has a
head of 78m and generates 300kW at full
power.
