Nuclear Energy nmnmost striking development in sources of power in recent years. nRnRelease of the...
Transcript of Nuclear Energy nmnmost striking development in sources of power in recent years. nRnRelease of the...
Nuclear Energy
Nuclear Energy
most striking development in sources of power in recent years.
Release of the atom
How long…..
Have we known about atomic power?
Ancient Greeks
included atomic theory as one of their philosophical studies
Knowledge about atoms was developed in the 17th century
Early 1900’s
theory became clarified
1940”s
atom was split resulting power was put to
work
Nuclear fission
the nuclei of heavy atoms are split under bombardment by neutrons
Nuclear fission
when a sufficient amount of fissionable material is brought together
chain reaction occurs
Nuclear fission
splitting atoms and releasing a tremendous amount of heat
Nuclear fission
approximately 20,000 times as much heat and energy is released from uranium fuels as from an equivalent amount of coal
Use of fission power
1945 first large scale use atomic bombs were used by
the US to knock Japan out of WWII
WWII
since then attention has been given to the peaceful uses of atomic energy
1980
the amount of electrical power generated by nuclear power plants was about 11% of the total electrical supplies in the US
Energy from fission
atomic energy in the US today is produced by the process known as nuclear fission
Fuel supplies
adequate supplies for nuclear power
major mineral sources for nuclear power
Uranium 238 Thorium 232
Fuel
from those - U 235 and Plutonium 239 can be produced
in the early stages of development US relied heavily upon imports of uranium
Fuel
from South Africa and Canada
1950’s and 60’s
western US deposits were developed
Bureau of Mines reported that -
.
“Domestic production is adequate to supply present and near-future domestic requirements.”
In 1981
US was still the world leading miner of uranium
Nuclear Fusion
Fusion is combining together the atoms are fused together
rather than split apart possibilities for nuclear fusion
are much greater than those for nuclear fission
Fusion
problems process is so difficult to
control that it is questionable whether commercial adaptation will ever be economically feasible
Problems
fusion requires extreme pressure and temperatures
as high as 100 million degrees
Problems
such heat was achieved by the Hydrogen bomb
by first setting off a fission explosion
Fuel for fusion
fusion reactors would be fueled by deuterium
an isotope of hydrogen available in almost unlimited
supply in sea water
US Government
demonstration fusion reactor hopes to have in operation
by 2015
LWR
Light Water Reactor use ordinary water have been in commercial
use since 1957
LWR
free from environmental problems of coal fired electric power plants
LWR disadvantages
potential of a reactor explosion
contamination form atomic wastes
construction costs and technical problems
Safety?
1974 report stated of Nuclear Power
Safety?
“its use poses serious environmental issues, including reactor safety, radioactive waste management and nuclear theft……..
Safety?
A very hazardous enterprise.”
Three Mile Island
March 28, 1979 Human and mechanical
failure led to the release of a considerable amount of radioactivity
Three Mile Island
evacuation of preschool children and pregnant women within five miles of the plant
Three Mile Island
Nevertheless 67 nuclear facilities are
expected to continued operating
90 were planned for construction by 1990
Safety Institutions
two Nuclear Safety Analysis
Center monitors performance of
safety
Safety Institutions
Institute of Nuclear Power inspects existing reactors
and evaluates them
Industrial Significance
peaceful use development of under-seas
and space nuclear power medical use of radioisotopes
Industrial Significance
research in nuclear physics ensnarled by many problems
technological, economic and social
Breeder Reactors
fast breeder reactors more efficient to operate
than LWR’s are undergoing experiment
Breeder Reactors
two types LMFBR Liquid Metal Fast Breeder
Reactor
Breeder Reactors
GCFBR Gas cooled fast breeder
reactor
Breeder Reactors
they produce more fuel than they consume
more efficient than LWR’s
Breeder Reactors
can use 50-70% of the uranium mined in contrast to only 2% by the LWR
Breeder Reactors
safety problems for the LMFBR may prove to be more sever than those of the LWR
1950’s
Atomic Energy Commission stated:
all new power plants under construction would be atomic powered
1950’s
nuclear energy would account for one half of all the electricity generated
1950’s forecast
does not seem likely to happen
it takes 10-12 years to get a nuclear plant in operation from the first time it is planned
1950’s forecast
no new plant orders were signed in the early 1980’s due to the Three Mile Island accident.
1974
American Scientists and Engineers completed a study
assessed the possibilities of accident risks in nuclear reactors…...
Conclusion……
“The odds of an American dying from a nuclear power accident are 300 million to one.”