Energy resources - Topic 2 Flashcards
Definition of renewable?
Produces at the same rate that is it used. (Doesn’t run out)
Definition of non-renewable?
Used up at a faster rate that they are produced- has a finite supply
Non-renewable energy resources will ___ ___ one day.
run out
Renewable energy resources will ___ ___ ___.
Not run out
What are the three main fossil fuels?
Coal, oil , (natural) gas
Name 7 renewable energy sources.
Solar, Wind, Tidal, geothermal, bio-fuel, hydroelectricity, wave
What is a non-renewable energy resource that isn’t a fossil fuel?
Nuclear energy
Are fossil fuels reliable?
Yes
How does wind power provide electricity?
- Wind turns the blades of a wind turbine, which turns an internal generator
- The kinetic energy is transferred into electrostatic energy/ electricity
Cons of wind power
- spoil the view: need 1500 wind turbines to replace one coal- fired power
- very noisy: annoying for people living nearby
- unreliable: if wind stops to if wind is too strong, its impossible to increase supply when there’s extra demand
- initial cost are high: but no fuel or running costs
Pros of wind power?
- no fuel costs and minimal running costs
- no pollution
- no permanent damage: if removed, noise is also gone and view is back to normal
How does solar power provide electricity?
Sunlight hits solar cells which transfer it directly into electrostatic energy in electric currents.
Cons of solar power?
- initial costs are very high
- takes up a lot of space
- needs to have sunlight to doesn’t work
- can’t increase power output when there’s extra demand
Pros of solar power?
- running costs are almost at nil
- no pollution
- best source to charge batteries which dont need much energy : calculators, watches
How does geothermal energy provide electricity?
Hot, nuclear rocks near to the surface in volcanic areas are used to heat water. The water becomes steam, which rises and turns a turbine. This turns a generator, which provides electricity.
Cons of geothermal energy>
- aren’t many suitable locations
- cost of building a power plant is often high compared to the amount of energy it produces
Where does geothermal work best?
volcanic areas
Pros of geothermal energy
- brilliant free energy that is reliable
- little damage to environment
Where does solar work best?
remote sunny places and small devices
Where does wind work best?
exposed places like moors or on the coast
How does hydroelectricity provide electricity?
water is steadily released from a man-made dam in a high-up area. It flows downhill and turns a turbine, which turns a generator, which generates electricity.
Pros of hydroelectric power
- no pollution
- can provide immediate response to an increased demand for electricity
- no fuel cost + minimal running costs
Cons for hydroelectric power
- big impact on the environment: flooding of the valley (rotting vegetation releases methane and CO2)
Loss of habitat - unreliable if drought occurs
- initial cost are high
- look ugly once dried up
Where does hydroelectric power work best?
in valleys or high-up areas
How does wave power generate electricity?
small turbines floating in the ocean are spun by the waves. This spins internal generators and generates electricity. Electricity is transported by wires on the seabed.
Cons of wave power
- disturbance to the seabed and habitats of marine animals
- hazardous to boats
- ruins the view
- fairly unreliable: waves tend to die out when wind drops
- never like to produce energy on a large scale
- initial costs are high
pros of wave power
- very useful on small islands
- no pollution
- No fuel costs + minimal running cost
Where does wave power work best?
around the coast, in the sea
How does tidal barrages generate electricity?
- barrages are built across estuaries.
- The tide fills the estuary and water is let out into the sea through a turbine at a controlled speed.
- The turbine spins and turns a generator which generates electricity.
Cons of tidal power
- prevents free access by boats
- spoils the view
- alters habitats of the wildlife: wading birds, seas creatures, migrating animals
- drawback: the height of the tide is variable so lower (neap) tides will provide much lesson energy than the big ‘spring’ tides
- don’t work when water level is same on either side- happens 4 times a day
Pros for tidal power
- no pollution
- pretty reliable: happen twice a day without fail, and always near to predicted height
- no fuel cost + minimal running costs
Where does tidal power work best?
River estuaries
How does biomass generate electricity?
biofuels (can be solid, liquid, gas )are burned to heat water, which becomes steam and rises to turn a turbine. The turbine turns a generator which generates electricity.
Cons of biomass power
- growing crops specially for bio-fuels mean that there isn’t enough space or water to meet demands
- some regions, large areas of forest have been cleared to make room to grow bi-fuels, resulting in lots of species losing their natural habitats.
-cost to refine bio-fuels is very high - can’t respond to immediate energy demands
Pros of biomass power
-carbon neutral (only keep planting trees at same rate)
- fairly reliable: crops take relatively short amount of time to grow and different crops can be grown all year round
Where does biomass energy work the best?
anywhere with large spaces, sometimes forests or plantations
What can take years to do with a nuclear power plant?
decommission
What do fossil fuels release?
CO2: greenhouse gas, traps heat in our atmosphere, causing global warming.
Sulfur dioxide: causes acids rain, harmful to trees and soils and can have far-reaching effects in ecosystems.
