Energy Generation Flashcards
What are fossil fuels
- Fossil fuels are formed from the fossilised remains of plants and animals over millions of years
- Coal, oil and gas are extracted through mining and drilling
How are fossil fuels used to generate energy
Fossil fuels can be burned to superheat water under pressure, which in turn, drives turbines, this kinetic energy is then used to generate electricity.
What is fracking?
• Fracking involves drilling into layers of shale rock deep in the earth to release pockets of gas
• Water, sand and chemicals are injected into a well in order to force gas back up
What are the disadvantages of fossil fuels
- a finite resource
- releases CO2 into atmosphere, causing climate change
- mining process is also often negative for the environment
What are the renewable alternatives to fossil fuels
• Wind
• Solar
• Tidal
• Biomass
• Hydroelectric
What are the positives of wind turbines
- low maintenance
- clean energy
- Higher winter output (when energy is needed most for heating)
- low energy cost
What are the negatives of wind turbines?
- only work when windy
- eyesore to some
- hazard to birds
- noise
How do Photovoltaic cells work (solar energy)?
Light photons hit the PV cell which allows electrons to flow, creating an electric current
What are the advantages of using PV cells to harness solar power?
- low maintenance
- clean energy
- relatively low-cost
What are thedisadvantages of using PV cells to harness solar power?
- seasonal fluctuations
- No power generated at night
- complex positioning issues
How does tidal energy work?
The rise and fall of the tide forces water through
turbines which drive generators to produce electricity
What are the advantages of Hydroelectric power (HEP)?
Hydroelectric power is a very reliable and controllable energy source
What are the disadvantages of Hydroelectric power (HEP)?
• The set-up costs are financially and environmentally expensive
• Vast areas need to be flooded to create reservoirs
- these reservoirs displace people and animals living in the local area.
- larger reservoirs can potentially increase the risk of earthquakes if placed near a plate boundery
What is biomass and how does it generate power?
Biofuel and biomass are created from organic matter which is burned to generate power
• Biomass fuels include food and farm waste, compost and wood chips or compressed pellets
Why is biomass considered to be carbon neutral?
Because the carbon released is the same amount as the carbon absorbed by the biomass.