Download Light-Water Reactors

DO NOW
1.
What is the difference between a renewable and a nonrenewable
resource?
2.
3.
What is the formula for power?
Name the six forms of energy discussed in the previous lesson.
NUCLEAR AND HYDROELECTRIC
ENERGY
ENERGY
LESSON 2
NUCLEAR FUSION
• Atoms are forced to collide and then fuse, which
releases large amounts of energy
• In order to produce 10,000 megawatts of
electricity, a coal-fed plant would have to release
30,000 tons of CO2 gases, 600 tons of SO2 gases,
and 80 tons of NO2 gas
• A nuclear fission plant can produce the same
10,000 megawatts of electricity and only release 4
pounds of harmless helium as a waste product
NUCLEAR FISSION
• Main process for creating nuclear
energy
• Exothermic reaction-gives off heat
• If not controlled, could result in a
nuclear explosion
• Nuclear waste is highly radioactive
and hard to get rid of
• Nuclear power has a higher
potential energy than all other
sources
TYPES OF NUCLEAR REACTORS
•
Light-Water Reactors are the most easy
to construct and operate, as well as the
least expensive to build; generally the
safest
•
Heavy-Water Reactors use a form of
water (D2O) that is heavier, atomically,
than H2O
•
Graphite-Moderated Reactors were
created by Russian scientists, and
generally unstable, and resulted in the
Chernobyl Disaster of 1986
CASE STUDY: CHERNOBYL
ENVIRONMENTAL ADVANTAGES &
DISADVANTAGES OF NUCLEAR POWER
Pros
Cons
No air pollutants
Nuclear waste takes millions of years to degrade
(half-life) and is difficult to store
Releases one-sixth of the CO2 of fossil fuel plants
The process of commissioning and
decommissioning nuclear power plants is
regulated by the Nuclear Regulatory Commission
and is costly and dangerous
Water pollution is low
Low-net energy yield; energy is required for
mining uranium, processing ore, building and
operating the plant, dismantling the plant, and
storing wastes
Land disruption is low to moderate
Safety and malfunction concerns
RADIATION AND HUMAN HEALTH
• Chernobyl Nuclear Reactor Meltdown-Ukraine, 1986
• 3 Mile Island Nuclear Disaster-United States, 1979
• Fukushima Nuclear Reactor Meltdown-Japan, 2011
HYDROELECTRIC POWER
• Dams are built to trap
water which in turn is then
released and channeled
through turbines that
generate electricity.
Hydroelectric power
supplies about 10% of the
electricity in the U.S. and
about 3% worldwide
ENVIRONMENTAL ADVANTAGES &
DISADVANTAGES OF HYDROELECTRIC POWER
Pros
Cons
Dams control flooding
Dams create large flooded areas behind the dam;
displaces people; slow water breeds pathogens
Low operating and maintenance costs
Dams destroy wildlife habitats and prevent fish from
migrating
No polluting waste products
Sedimentation doesn’t reach farmland
Long life spans
Expensive
Moderate to high net-useful energy
Destroys wild rivers; water loss because of increased
evaporation
Areas of water recreation
Large-scale projects are subject to earthquakes
SALMON, SILTING, AND OTHER IMPACTS
•
Dams prevent salmon from completing their
journeys upstream to reproduce
•
Reservoirs in tropical areas have slow moving or
still water, which is a breeding ground for
infectious disease
•
Displacement of people due to flooding and
destruction of croplands
•
Deprives downstream areas of nutrient-rich water
•
Silt particles build up behind dams and must be
removed/dredged