Transcript Flowing Water

Flowing Water
By Mike, Holt, Natalie, Claire,
Megan
Hydropower
Hydropower is power derived from the energy of flowing water that can
be harnessed for a number of purposes.
Historically, hydropower has been used for irrigation in croplands,
factories, and operation of various machines.
Currently, we are leaning toward electricity from hydropower because
of it’s high net energy and efficient use.
Large Scale Hydropower
Large Scale utilizes a high dam that is built across a large river to
create a reservoir upstream of the dam. The dam lets some of the
water through that is stored in the reservoir flow through huge pipes
where the flowing water spins turbines connected to generators that
create electricity.
Small Scale Hydropower
Small scale hydropower consists of sometimes a low dam, turbine
wheel, or generator with no reservoir built up. Typically this
hydropower is used in remote areas across small streams where
there is little environmental impact and water diversion from the
hydropower system.
Pumped Storage Hydropower
Water from a higher reservoir
flows water through a plant in a
lower reservoir where they
spin turbines creating
electricity. Then pumps using
surplus electricity from a
conventional power plant
pump water from the lower
lake or a reservoir to the
reservoir at a higher elevation.
When more electricity is
needed, water in the upper
reservoir is released where it
flows through turbines and
generates more electricity on
it’s return to the lower
reservoir.
Hydropower World Use
Hydropower contributes to 6% of the
world’s commercial energy use. 3-4% in
the United States. It makes 20% of the
world’s electricity; other countries have
found ways to rely mostly on flowing
water as a energy source: Norway
obtains 99% of its electricity from
hydropower, New Zealand is 75%, and
China is 25%.
Advantages and Disadvantages
Advantages
Disadvantages
•Moderate to high net energy
•High efficiency (80%)
•Low cost electricity
•Long life span
•No CO2 emissions during
production
•Provides flood control below dam
•Year round irrigation to cropland
•Reservoir is useful for fishing and
recreation
•High construction cost
•High environmental impact
•High CO2 emission from biomass
decay in shallow tropical areas
•Floods natural areas
•Converts land habitat to lake
habitat
•Danger of collapse
•Uproots people
•Decreases fish harvest below
dam
•Decreases flow of natural
fertilizers below dam
“Improving the efficiency of
hydropower stations”
This article states that Hydropower provides 16% of Europes
Electricity but most of their hydropower plants are old and
outdated. By redesigning their runners, the propeller part of
the turbine which spins to produce the energy, they can obtain
more power from the turbines. So various plants are taking on
this redesigning project which could enable the plant to store
even more power and manage high peak demands.
http://www.eurekalert.org/pub_releases/2003-03/e-ite031203.php
Let water power your cell
phone?
Researchers from the University of Alberta have found a way to
produce electricity by flowing, pressurized water in which various
uses would apply from powering a cell phone to a national grid line.
When talking about small appliances like cell phones and
calculators, they have managed to create electricity by flowing water
through tiny micro-channels which act as microscopic hydro plants
creating power.
http://www.eurekalert.org/pub_releases/2003-10/uoa-lwp101403.php
Sources
Wikipedia.com
Eurekalert.com
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