Fuel for Electricity
-In most power stations, water is heated to produce steam. The steam drives a turbine, which is coupled to an electrical generator that produces the electricity
A biofuel is any fuel obtained from living or recently living organisms. Some biofuels can be used in small-scale, gas-fired power stations.
-Biofuels are renewable sources of energy
-More energy is released per kg in nuclear power than from burning fossil fuels
-Nuclear power stations do not release any greenhouse gases, unlike fossil-fuel power stations. However, nuclear power stations do produce radioactive waste that must be safely stored for a long time
Wind Power-can use wind and water to drive turbines directly
-Renewable
-In a wind turbine, the wind passing over the blades makes them rotate and drive a generator at the top of a narrow tower
In a pumped storage system, surplus electricity is used, at times of low demandnto pump the water back up the hill to the top of the reservoir(energy is stored)
Wave power-uses the movement of waves on the sea to generate electricity
-The movement drives a floating turbine that turns a generator
-Then the electricity is delivered to the grid system on shore by a cable
Solar energy from the sun travels through space to the Earth as electromagnetic radiation
We can also join together large numbers of cells to form a solar panel. Water flowing through a solar heating panel is heated directly by energy from the sun
Geothermal energy is produced inside the Earth by radioactive processes and this heats the surrounding rock. In volcanic areas, very deep holes are drilled and cold water is pumped dwon to the hot rocks
The rate at which we use fossil fuels is much faster than the rate at which they're produced- non-renewable
The cables are carried long distances across the countryside supported by overhead pylons. In towns and close to homes the cables are buried underground
The greater the voltage, the smaller the current, the smaller the energy loss
Base load demand- the constant amount of electricity provided by nuclear, coal-fired and oil-fired power stations
This variable demand is met using gas-fired power stations, pumped-storage schemes and renewable enery sources
Different types of power stations have different start-up times. Gas-fired power stations have the shortest start-up times and nuclear power stations have the longest