Nuclear Power And Energy Storage Flashcards
What is nuclear fission?
This is when a neutron hits the nucleus of 235 uranium or plutonium atom and causes the nucleus to split into two new nuclei . These fissions release energy and neutrons. These released neutrons may hit other uranium or plutonium nuclei causing new fissions. This is called a chain reaction.
How is reaction rate controlled in commercial reactors?
In commercial reactors rods are installed that control reaction rate by absorbing excess neutrons.
What is a nuclear power plant?
These are thermal power plants that generate electricity by harnessing the thermal energy released from nuclear fission.
What is a nuclear power plant composed of?
A nuclear reactor (this where the reaction that generates heat occurs)
A cooling system (removes heat from the reactor)
A steam turbine (converts heat to mechanical energy)
A generator (converts mech. Energy to electrical energy)
What nuclear power fuels?
Common one is uranium. Uranium is mined and processed into enriched uranium 235.
U235 is usually referred to as low enriched uranium.
High enriched uranium is usually used for weapons etc.
Nuclear energy waste?
This is a big problem because of how radioactive and unstable the waste is .
High level waste is usuallly stored in spent fuel pools , where they are cooled and shielded from radiation for about 6-10 years.
After they are cool enough they are transferred to dry cask storage.
The radioactive decreases with time in approximately 100 years it would have decreased by 99.5%.
The more intensely short lived fission products decay after 300years and after 100,000 years it is less radioactive than natural uranium ore.
What are some of the nuclear power risks and environmental consequences?
The possibility of Nuclear accidents eg Chernobyl and Fukushima.
The possibility of nuclear facilities to be used in sabotage,War , terrorism.
There is also the need to store nuclear waste long term that .
The fear of this energy being used of for nuclear weapons.
However it is important to note that nuclear energy has the lowest number of accidents as compared to other energy sources and is considered as having the lowest fatalities per enery unit.
Nuclear power present and future.
There are currently about 410 civilian nuclear fission reactors with a capacity of 369 GW.
There are 57 new ones under construction and 102 planned with a combined energy of 59 and 96 respectively.
Looking at the trend costs in 2010 and 2019 it looks like nuclear power is on an upward trajectory true or false .
True
Nuclear power fusion
This is when two lighter atomic nuclei combine to form a heavier nucleus while releasing energy.eg of such nuclei deuterium,helium tritium. Very high temps and pressure
Advantages of nuclear fusion compared to fission.
Reduced radioactivity
Limited amount of high level waste
Ample fuel supplies
Has increased safety
Disadvantage of nuclear fusion
It’s very difficult to produce in a practical and economic way.
What are the different storage methods and their discharge times
Fly wheel (stores kinetic energy): stores small amount of energy fr a couple of minutes
Batteries: can store some amount of energy for a couple of hours
Compressed air storage: can store moderate amount of energy for about half a month
Pumped storage: can store moderate energy for almost a month
Hydrogen (power to gas) : can store relatively large amounts of energy for a month
Methane (power to gas) : can store large amounts of energy for a whole year .
What are some fun facts about pumped storage?
There are 600 sites identified globally that are suitable for pumped storage.
It. An respond to load changes in seconds
Write what you know about batteries
Types
Lead acid
Flow
Li-ion
Used to stabilize grid in less than a second
Short term peak power (hours)
Smaller than pumped storage but growing quickly.
A large number can be widely deployed across a grid.
