National and global energy resources Flashcards
What is a renewable energy resource?
An energy resource which can be replenished as it is being used up
Give seven examples of renewable energy resources
- Wind
- Tides
- Solar
- Bio-Fuel
- Water Waves
- Geothermal
- Hydroelectricity
What is a non-renewable energy resource?
A resource that cannot replenish as it is being used up
Give four examples of non-renewable energy resources
- Coil
- Oil
- (Natural) Gas
- Nuclear Fuels
State two disadvantages of using renewable energy resources to generate power
- Output often determined by external factors (like wind speed), so supply is uncertain
- Generating power through other means is often more efficient and economically beneficial
Describe how fossil fuels generate electricity
Burning fossil fuels > heats water > steam produced > turns turbines > turns generator > electricity produced
State some advantages of using fossil fuels to generate electricity
- Provide a cost-effective resource that produces large amounts of energy and is readily available
- Running costs are fairly low
- Reliable - there’s enough fuel to meet current demand and power plants can respond quickly to changes in demand
Explain the environmental impacts of burning fossil fuels
- Carbon dioxide contributes to the greenhouse effect, and causes global warming
- Sulphur dioxide leads to acid rain, which can damage buildings and crops
- Coil mining makes a mess of the landscape
- Oil spillages cause serious environmental problems, affecting animals
Describe how nuclear fuels generates electricity
- Nuclear fission of nuclear fuels e.g. uranium or plutonium releases the energy to heat water into steam
- The steam drives turbines which drives a generator that produces electricity
State three advantages of nuclear power
- Very large amounts of energy for relatively small quantities of fuel
- Doesn’t release greenhouse gases and so doesn’t contribute to climate change
- Low fuel costs
State three disadvantages of nuclear power
- Produces nuclear waste which is harmful to humans & must be safely stored for centuries.
- Non-Renewable energy source
- Risk of nuclear accidents, which have fatal consequences on humans and the environment
Describe how hydroelectric power generates electricity
- Rainwater is collected behind a dam
- When this water is released, it is used to turn a turbine
- The turbine turns a generator which produces electricity
State some advantages of using hydroelectric power to generate electricity
- No pollution
- Can provide an immediate response to an increased demand for electricity
- Reliable - except in cases of drought
State some disadvantages of using hydroelectric power to generate electricity
- The dam may cause flooding - can lead to rotting vegetation (which releases CO2 and CH4) and possible loss of habitat (for both animals and humans)
- Can cost a lot to install the required infrastructure
- The reservoirs can also cause visual pollution
Describe how wave power generates electricity
- Waves force air through a turbine
- The turbine turns a generator which produces electricity
State some advantages of using wave power to generate electricity
- No pollution
- No fuel costs and minimal running costs
State some disadvantages of using wave power to generate electricity
- Disturb the seabed and the habitats of marine animals
- Visual pollution
- Fairly unreliable since waves tend to die out when the wind drops
- Never likely to provide energy on a large scale
Describe how tidal barrages generate electricity
- Tide water is held back behind the barrage
- The water is eventually allowed to flow through turbines connected to generators, generating electricity
State some advantages of using tidal barrages to generate electricity
- No greenhouse gases produced
- Quite reliable as tides happen twice a day
- Cheap to run as tides are natural
State some disadvantages of using tidal barrages to generate electricity
- Prevents access to boats
- Visual pollution
- Altering the habitat of the wild life
Describe how bio-fuels generate electricity
- Bio-fuel is let in a boiler and is burned
- Energy is released and water is heated to produce steam
- The steam turns a turbine which turns a generator, generating electricity
State some advantages of using bio-fuels to generate electricity
- Quite reliable - crops take a short time to grow
- Renewable
State some disadvantages of using bio-fuels to generate electricity
- Cannot respond to immediate energy demands
- When plants are burned or decay, they release CO2
- Bio-fuel production also creates CH4 emissions
- Large areas of forest have to be cleared - lots of natural habitats are lost
Describe how geothermal power is used to generate electricity
- Hot water and steam from underground rises
- Drives a turbine which is connected to a generator, generating electricity
State some advantages of using geothermal power to generate electricity
- Reliable
- Does not impact the environment
- Cost effective once the power station has been built
State some disadvantages of using geothermal power to generate electricity
- There are not many suitable locations for the power stations
- Cost of building a power station is high
Describe how solar cells are used to generate electricity
- Converts the sun radiation directly into electricity
- Can be plugged straight into electrical components
State some advantages of using solar cells to generate electricity
- Reliable in some countries
- Renewable
- No pollutants
- Best source of energy for small devices e.g. calculators
State some disadvantages of using solar cells to generate electricity
- Not useful in countries which are not exposed to the sun such as Britain
- Used for small scale projects
Describe how wind power is used to generate electricity
- Turbine blades rotate in the wind
- Gears are used to link the turbine blades to the generator
- The turbine drives a generator, which produces electricity
State some advantages of using wind power to generate electricity
- No pollutants
- No fuel costs and minimal running costs
State some disadvantages pf using wind power to generate electricity
- Many wind turbines are needed to generate a substantial amount of electricity
- Noise pollution
- Visual pollution
- Unreliable - the wind is not always blowing
- Initial costs are high
