1.2 - Energy Generation and Storage Flashcards
How exactly are fossil fuels used to generate electricity?
- Production of electricity involves rotating a turbine which turns a generator.
- Fossil fuels are commonly burned to create heat which superheats water.
- The resultant steam rotates the turbine which is linked to a generator to produce electricity.
What are fossil fuels?
- Fossil fuels are finite resources.
- Natural gas is a main source of power for electricity in the UK. It’s also used for heating and cooking.
- Coal is burned to create energy.
- Oil is mainly used to produce plastics or for fuel.
- Burning these fuels produces large amounts of CO2 which contributes to climate change.
What are the advantages of fossil fuels?
- A cheap and reliable source of energy.
- There are well developed systems to harness the energy.
What are the disadvantages of fossil fuels?
- Contains high amounts of carbon and contributes to global warming.
- A non-renewable and unsustainable energy source.
- Accidents such as oil spills contribute to pollution and environmental contamination.
What is fracking and shale gas?
- Hydraulic fracturing or fracking is a process for extracting the shale gas
- Shale gas is a natural gas trapped in the earth’s crust.
- This is done by sending a high pressure mixture of water, sand and chemicals into the rock to release the gas.
What are the specific advantages of coal?
- Reliable. Enough coal on Earth to last hundreds of years.
- Produces high amounts of energy.
What are the specific disadvantages of coal?
- Produces carbon dioxide when burned, contributing to global warming.
- Damage is caused to natural land when mining takes place.
What are the specific advantages of gas?
- It emits less carbon dioxide than coal or oil.
- The UK has shale gas deposits.
What are the specific disadvantages of gas?
- Gas is highly flammable - if there is a gas leak, an explosion can easily happen.
- Extracting gas might cause the pollution of water
What are the specific advantages of oil?
- A small amount of oil can produce a lot of energy.
- It is relatively easy to store and transport.
What are the specific disadvantages of oil?
- Creates significant air pollution when burned.
- Considerable impact on water, land use and disposal.
What are some negative effects of fracking?
- Disposal of drilling wastewater used in fracking has been linked to an increased risk of earthquakes
- Fracking can contaminate water supplies if it is not done properly.
A nuclear power plant produces energy through a process called _______ - the splitting of uranium atoms in a nuclear reactor.
fission
How is nuclear power used to generate electricity?
- A nuclear reaction which takes place inside a reactor.
- This releases a large amount of energy as heat.
- The heat is used to generate steam which drives turbines to produce electricity.
What are the advantages of using nuclear power?
- Nuclear power is clean and efficient.
- Nuclear energy runs continuously and reliably generating large scale power.
What are the disadvantages of using nuclear power?
- The waste material is radioactive and dangerous to life and so requires specialist handling, decommissioning and lots of storage space. This is very costly.
- Cost of nuclear power stations is very large.
- Nuclear power stations have to close after around 40 years of use when the uranium becomes less efficient at heating the water.
What is renewable nergy
These are natural sources of energy that are non-finite and can be quickly replenished.
What are some examples of renewable energy?
- Wind
- Wave
- Tidal
- Hydroelectric
- Geothermal
- Biomass
- Solar energy
How is wind power used to generate electricity?
- Wind turbines convert kinetic energy from the wind into electricity.
- The energy of the wind turns the propeller-like blades on the rotor.
- This is connected to a generator which creates the electricity.
What are the advantages of wind power?
- Wind energy is now very cost effective to produce.
- Running cost of a wind turbine is relatively low.
- It is a clean source of energy and is sustainable and renewable.
What are the disadvantages of wind power?
- When there are periods of low wind, little or no energy is produced.
- They cost a lot to build and put in place.
- Some people do not like the look of wind turbines or feel that they spoil the natural landscape.
- The distance from remote wind sites and connection costs to the national grid may be significant.
How is tidal power used to generate electricity?
- Tidal power converts energy from tides into power.
- The movement of water turns underwater turbines, which drive the generators that convert the energy into electricity.
- Tidal barrage systems utilise the difference between low and high tides.
- Tidal stream power utilises fast flowing currents around coasts and islands.
What are the advantages of tidal power?
- A constant, predictable, renewable energy source which is clean.
- Tidal power plants will last for a long time.
What are the disadvantages of tidal power?
- Expensive to set up and maintain.
- Environmental impact of tidal barrages is unknown.
How are solar panels used to generate electricity?
Solar panels absorb light into photovoltaic cells which is converted into electricity.
What are the advantages of solar power?
- Renewable, clean power, no greenhouse gases.
- Energy can be collected on sunny or cloudy days.
- Reduces household energy bills.
What are the disadvantages of solar power?
- Energy generation levels are lower in winter months when daylight hours are shorter.
- Energy generation varies depending on how cloudy it is.
- Costs a lot to install.
- Some people do not like the look of solar panels or feel that they spoil the appearance of a building.
How is biomass energy used to generate electricity?
- Biomass energy is produced from organic matter such as plants, crops, wood chips and animal waste.
- The energy can be extracted by burning or anaerobic digestion, which creates a biogas and a biofertiliser.
What are the advantages of biomass energy?
- A renewable form of energy with a plentiful supply of material.
- Carbon neutral. Since, in theory, emissions from burnt plants are reabsorbed when biofuel crops are regrown.
What are the disadvantages of biomass energy?
- Risk of deforestation if trees are not replanted.
- Creates atmospheric pollution when burned.
- Large amount of land used for growing energy crops.
How is hydroelectric power (HEP) used to generate electricity?
- Hydroelectric power (HEP) captures the energy of falling water.
- A turbine converts this kinetic energy into mechanical energy, and a generator turns this to electricity.
- Dams are the most common structures used for harnessing hydroelectric power.
What are the advantages of hydroelectric power?
- Hydroelectric energy is renewable and does not pollute.
- Reliable energy source.
- Energy generation can be regulated according to demand by opening and closing valves.
What are the disadvantages of hydroelectric power?
- The local environment is affected by flooding of a valley, which impacts on surrounding water flow. This in turn affects natural irrigation and ecosystems.
- Construction of dams is expensive.
- Objections from people in the local area.
What is kinetic energy?
- Kinetic energy is the energy an object has because of its motion.
- Hydroelectric facilities harness the powerful force of gravity to enable this form of energy storage. The facilities comprise of two reservoirs and a hydroelectric dam system.
How do kinetic pumped storage systems work?
- A hydroelectric storage facility holds water in an upper reservoir.
- At times of high electricity demand, the dam is opened and the water released into a lower reservoir to drive the turbines, producing electricity.
- At times of low electricity demand, such as at night, the water is pumped back up to the upper reservoir ready for the cycle to continue.
Why is it important that battaries are disposed of correctly?
- Batteries contain chemicals that are toxic and should be disposed of correctly at a recycling centre.
- If batteries end up in landfill, the chemicals can contaminate the ground causing soil or water pollution, harming the environment.
How do batteries produce an electric voltage?
Batteries contain electro-chemicals that react with each other to produce an electric voltage.
What are the properties of an alkaline battery?
- Alkaline batteries have a high energy capacity and long shelf life.
- Once the chemical reactants have been used, the battery is flat and no longer usable. The power output gradually decreases.
- A typical battery holds 1.5 volts per cell.
What are the properties of a rechargable battery?
- Rechargeable batteries can be recharged a limited amount of times.
- The power output remains constant until they run flat.
- Available in different types for higher powered uses.
- A typical rechargeable battery holds 1.2 volts per cell.
