Renewable energy sources Flashcards
What does wind power involve
Putting lots of wind turbines up in exposed places like on moors or coasts
How do wind turbines work
They contain a generator
The electricity is generated directly inside the turbine from the wind turning the blades which turn the generator
What are the 4 advantages of wind power
- No pollution
- Renewable
- No permanent damage to the physical landscape
- No fuel cots and minimal running costs
What are the 4 disadvantages of wind power
- Unreliable - no power when the wind is not present
- They can be noisy - this can disrupt locals
- They spoil the view
- Initial costs are high
What is solar power
Solar cells generating electric currents directly from sunlight
What 2 things is solar energy best for
Calculators
Watches
What are 3 advantages of solar power
- Can be used in remote areas and sunny countries
- No pollution
- Free energy and no running costs
What are 3 disadvantages of solar energy
- Unreliable - If no sun there’s going to be barely if not any solar energy
- Initial costs are high
- Generates only a small amount of electricity
What are 3advantages on HEP
- Immediate response to an increase in demand for electricity
- No reliability problems except in drought
- No pollution
What are 3 disadvantages to HEP
- Requires the flooding of a valley by building a big dam
- Big impact on the environment due to the flooding of the valley
- Only generates small scale electricity in remote areas
What does Pumped storage do
Give extra supply when needed
Why do we need pumped storage
Most power stations have a huge boiler which needs to be kept running all night although demand is low which creates a surplus in electricity and pumped storage is the best way to store the spare energy for later use
What is the spare electricity used as in pumped storage
At night it is used to pump water to a higher reservoir and then it can be released quickly during periods of peak demand
Give 2 examples of peak demands
Meal times - tea time
National events - Olympics
Explain pumped storage
Over night, spare energy is used to pump water from a lower reservoir to an upper reservoir using a pump. The energy is released in peak demand through a turbine from upper to lower reservoir where the energy goes from turbine to generator
What do you need for wave power
Lots of small wave-powered turbines located around the coast
How does wave power work
As waves come into shore, they provide an up/down motion which can be used to drive a generator
What are 2 advantages of wave power
No pollution
Very useful on small islands
What are 3 disadvantages of wave power
Hazard to boats
Fairly unreliable
Doesn’t provide energy on a large scale
Why is wave power unreliable
Waves die down when the wind drops
What are tidal barrages
Bid dams built against river estuaries with turbines in them
How do tidal barrages work
As the tide comes in, it fills up the estuary to a height of several metres driving the turbines
The water can be allowed out through the turbines at a controlled speed
What is the source of energy for Tidal barrages
Gravity of the sun and the moon
What are 2 advantages of tidal barrages
No pollution
Reliable - happen twice a day without fail
What are 3 disadvantages of tidal barrages
Prevents free access by boats
Spoils the view
Alters habitat of wildlife
How does Geothermal energy work
Steam and hot water rise to the surface and are used to drive a generator
Where can Geothermal energy only be used
Volcanic areas where hot rocks lie quite near to the surface
What is the source of heat in geothermal energy
Slow decay of various radioactive elements
What is an advantage of geothermal energy
No environmental drawbacks
What are 2 disadvantages od geothermal energy
Aren’t many suitable areas for power plants
What are biofuels
Renewable energy sources
What states do biofuels come in
all
Where can we get biofuels
Organisms that are still alive or dead organic matter
