Energy Resources Flashcards
Energy from wind and water
• wind power
• wave power
• hydroelectric power
• tidal power
How are these energy resources used?
• electricity generator on top of a tall building
• waves generate electricity by turning a floating generator
• hydroelectricity generators are turned by water running downhill
• a tidal power station traps each high tide and uses it to turn generators
Power from sun and earth
• solar cells are flat solid cells and use the suns energy to generate electricity directly
• solar heating panels use the sun’s energy to heat water directly
• geothermal energy comes from the energy transferred by radioactive substances deep inside the earth
• water pumped into hot rocks underground produces steam to drive turbines at the earths surface that generate electricity
How are fossil fuels extracted?
• extracted from underground or under sea beds and transported to oil refineries and power stations
What other resources can power stations use?
• biofuels
• nuclear fuel
How does a power station work?
• in coal/oil fired power stations (and most gas) burning fuel heats water in a boiler
• produces steam
• drives a turbine that turns an electricity turbine
Biofuels
• any fuel taken from living or recently living organisms
• animal waste is a biofuel
• for example, methane gas can be collected from cows or animal manure, sewage works and decaying rubbish. Can be used in small gas fired power stations
How can biofuels be used ?
• in modified engines for transport
• generators at power stations
• biodiesel uses waste vegetable oil and plants such as rapeseed
Other examples of biofuels
• ethanol (from fermented sugar cane)
• straw
• nutshells
• woodchip
Benefits of biofuels
• carbon neutral
• renewable
Nuclear power/ fuel
• takes energy from atoms
• fuel in a nuclear power station in uranium (or plutonium)
• uranium fuel is sealed in cans at the core of the reactor
• nucleus of a uranium atom is unstable and can split in two. Energy is transferred from the nucleus when this happens. Becomes very hot
• energy of the core is transferred by a fluid called the coolant which is pumped through the core
• coolant is very hot when it leaves the core
• flows through a pipe to the heat exchanger then back to the reactor core
• energy transferred by coolant is used to turn water into steam in a heat exchanger and drive turbines that turn electricity generators
Why can’t we use solar cells for all of the UK?
Really large area of land would need to be covered by solar cells due to low useful power output
