How Does a Nuclear Power Plant Work?
Step 1 - Sourcing the Water A nuclear power plant has many different parts and requires a lot of water. Because so much water is required nuclear power plants are often located on the shores of lakes rivers and oceans. The water is used to cool down the waste heat discharge and to create steam. The water is taken from a source such as a lake and put in a cold-water basin underneath the cooling tower. From there the cold water is taken into the condenser where the water then goes into the steam generator.
Steam Generator
Condenser
Cold Water Basin
Lake
Step 2 - Generating Heat A nuclear power station works similar to a coal power station as they both heat water and use the steam to generate the heat. In a nuclear power station heat is made by using a process called fission. This heats the water inside the reactor vessel which is then cycles through the steam generator. Fission happens inside the reactor vessel in the fuel rods. The rods contain a fuel source which is often Uranium 235. The heat is generated by firing a neutron at Uranium 235 which causes it to split into two different elements called Krypton and Barium. This causes three other neutrons to fire into other uranium 235 atoms continuing the process and generating heat. A fuel rod often lasts about six years before being replaced. In the reactor vessel, there are also control rods which control the process and if completely submerged into the reactor vessel stop the process. The control rods are made out of a metal such as silver or boron that absorbs the neutrons, without fissioning themselves stopping the fission happening to quickly.
Uranium 235
There is also a moderator which is often made of graphite or sometimes water that slows down the speed of the neutrons. This stops the process from happening to quickly and becoming uncontrolled.
Neutron
Neutron Barium Neutron Krypton Uranium 235 Neutron
U
Containment Building
Uranium 235
Control Rods Reactor Vessel
Fuel Rods
Moderator
Steam Generator
Steam Generatrer
Step 3 - Producing Electricty The heated water from the nuclear reactor is cycled through the steam generator which heats the water creating stem. This steam then goes to the turbine. The steam pushes against the blades of the turning which causes the turbine to spin, this results in the generator being turned which creates electricity.
Turbine
Generator
Step 4 - Cooling the Excess Steam Once the steam has gone through the turbine the steam goes into the condenser where it is turned into water. The steam is condensed into water and then taken into the cooling tower where the steam goes back out into the atmosphere.
Turbine
Ho Condenser
ot Water
Cooling Tower
Step 5 - Disposing the waste
There are different gradings of waste, high, intermediate, and low. The level of danger determines how the waste is treated and where it is placed, the most dangerous deep underground, the lowest level nearer the top. al radioactive waste facilities are designed with necessary levels of protection. High level waste can remain radioactive for thousands of years. Here is the diffent types of waste and how much is generated in a nuclear power station in the UK.
Intermediate Waste About 9%
High Level Waste About 0.3%
Low Level Waste About 90%
Step 6 - Transporting the Electricity All the poles and wires seen across the countryside make up the electrical transmission and distribution system. Power plants are connected to each other through this system sometimes refferred to as the ‘national grid’. Transformers reduce the voltage to make the power safe to use.
Step 7 - Using the Electricty
The power travelling through the distribution lines connect to our neighbourhoods. The power lines connects to our personal systems through a meter that measures how much we use.
By Sam and Timothy