By Alex Liu
Electrical power is one of our most important resources. But where does all this power come from? How does it become electricity? We shine the spotlight on different power sources.
SOLAR POWER
Solar thermal electricity is energy that is harnessed from the sun. Solar energy is collected in a number of different ways, depending on the intended use for the energy:
-Low temperature collectors are plates used to collect heat during the day. These are used to heat swimming pools and homes.
-Medium temperature collectors are plates that are used to heat water in homes and buildings.
-High temperature collectors are mirrors and lenses that are used for powering large city areas.
PRO: Solar energy generators consume no fuel.
CON: They can put out a low level of energy compared to the amount of money spent on the system per year.
WIND POWER
With the use of wind turbines, wind can be transformed into a useable form of energy. This is done by placing windmills together in one area to create a wind farm:
– The energy is harnessed by the wind that turns the windmills.
– These mills are connected to a power transmission network.
– All of the collected energy is sent to the network through cables, which are then sent into substations.
– These substations are the generators that supply neighbourhoods with power.
PRO: Wind energy does not require physical fuel, as wind is one of the most renewable sources in the world.
CON: Because it is dependent on the wind, this form of energy generation is unpredictable. An alternative is to have a way of storing excess energy in times of no wind.
WATER POWER
Hydroelectricity is the name given to the energy source found in falling water. This form of power is extracted by damming water:
– By building a massive wall, water is forced to fall through holes into the dam.
– Inside the dam, there are machines known as turbines that connected to generators, which generate energy.
– The water falls through the turbines, spinning them, which in turn spins the generators, creating electricity.
PRO: Water is a renewable resource that can generate large amounts of power.
CON: Dams can sometimes affect surrounding marine life because it interrupts natural water flow.
NUCLEAR POWER
Nuclear power is produced inside a nuclear plant and is powered by atoms:
– This type of power begins with the process known as nuclear fission, which takes an atom and splits it.
– Nuclear fission occurs in the core of a nuclear reactor, where a radioactive material is placed.
– Here, one reaction causes the other atoms to split, creating a large amount heat.
– A coolant, most commonly water, is added and the resulting steam passes through tubes that lead to turbines, turning them and creating power.
PRO: It produces relatively low amounts of carbon dioxide, which means that its contribution to global warming is relatively small.
CON: Once nuclear fission occurs, gamma rays are released. These potentially harmful rays must be placed in large, water-filled tanks to cool, but storage spaces for the waste is becoming limited.