Energy Generation And Storage Flashcards
Fossil fuels to energy
Burn fuel ~ Heat water to make steam ~ Steam turns turbines ~ Turbines turn generators ~ Electrical power
Coal
Made from fossilized trees
23% of electricity from coal fired power plants
•have to import coal from abroad
Mining and burning coal produces waste and atmospheric pollution
Waste tips, stockpiles and open pits are unsightly and hazardous
Sulphur dioxide fumes
•acid rain
•atmospheric pollution
Advantages:
Doesn’t require processing before burning
Sufficient reserves of coal to last hundreds of years
Natural gas
Main source of power for electricity generation in the UK
•heating
•cooking
•industrial areas
Consists of methane mainly
Has to be processed to remove water and other impurities
Gas fired power stations can quickly be brought into service
Can be used in future as a replacement for less reliable sources
Gas from seas account for some of the gas we use
most comes from pipelines connected to Europe in liquefied form (LNG)
Shale gas under Britain
•if we use could cause pollution of water and seismic tremors
Advantages:
•burnt directly - no crushing
•easy to transport through pipelines
Oil
Hardly used for energy production in the UK Some heating systems •rural areas away from main gas supply Main fuel in road and sea transportation Refined from crude oil Will run out before coal Amount of oil in North Sea has reduced
Nuclear power
22% of UK’s electricity from nuclear reactors
Uranium atom split to produce heat - fission
Convert water to superheated steam which drives turbines
Current nuclear power stations are expected to close by 2025
•old
•end of serviceable life soon
Some replacements are planned
Disposal of unused power stations is expensive
•can result in nuclear material leaking
•highly hazardous for thousands of years
Percentage of energy used by the UK
Coal 23% Oil less than 1% Gas 30% Nuclear 22% Renewable 25%
Wind
Used for thousands of years •windmills Wind turbines are best on the coast, offshore or on a hilltop Tower needs to be high for long blades •land underneath can still be used
Solar
Passive: placing most windows on south side of building
Active: photovoltaic cells
Amount is vast - outstripping all other deposits in a year
Closest to equator is most efficient
Photovoltaic cells take up land
•cells on roofs and sides of tall buildings
Tidal
Relies on gravitational pull of the moon
20% of energy needs for Britain come from tides
Tidal barrage
•incoming tide passes through turbines
Could flood mudflats and be difficult for waste disposal
•many times discharge sewage into rivers
Water
Harnessing the power of moving water for many years
Dam blocks rivers, water stored in a reservoir, then channeled through turbines that turn generators
Main cost is building dam
Electricity can be produced very quickly
Environmental effects:
• Valley floods
• reducing water flow below the dam
• can affect the growing of crops and river ecosystems
Wave
Difficult to harness
Positioning is critical
Biomass
Growing plants so that they can be burnt
Or decaying plant or animal materials to produce heat
Some vegetable oils are treated after being used for cooking; after processing they are suitable for diesel engines
Grown as biomass crops:
• oilseed rape
• willow
Causes atmospheric pollution
Uses land that could be used for growing food
Energy storage systems
Mechanical
Flywheels - continue to spin after driving force stops:
Used in some buses and clock work
Works with potential energy
Energy storage systems
Electrical capacitators
Most popular non chemical method of storing energy
Predates the battery
Electrical vehicles
Can be recharged more than batteries
Energy storage systems
Batteries
Single use - the main ones we use in once and throw away - primary
Alkaline and zinc carbon - have 1.5 volts per cell
Rechargeable - secondary
Cheaper overall but more expensive to buy
Nickel cadmium and lithium ion - 1.2 volts per cell
There is an issue relating to safe disposal
