P3.2 - Renewable energy. Flashcards
renewable energy meaning
- natural sources of energy
- can never be used up
- no fuel is needed to produce electricity
- carbon -free
Wind power
-wind turns a turbine which power a generator
-which is at the top of a narrow tower
-
Wind power generated increases as …
the wind speed increases
Wave power
-uses waves to make a floating generator move up a dam
-this motion turns the generator = electricity
-
Hydroelectric power
- rainwater (collected in a reservoir) flows down a hill
- flowing water drives a turbine= electricity at the bottom of the hill
Tidal power
- traps water from each high tide behind a barrage
- then is released through sea turbines = powers generator in barrage
solar radiation
- transferred by the sun
- generates energy using solar cells
solar cells
flat solid cells
-use the sun’s energy to generate electricity
solar heating panels
- heat water directly
- water in tank runs through pipes in panels and heats up
- turn to steam = electricity
Where is solar energy best used?
- in places where small amounts are needed
- eg calculators
- or in remote places
Pros/ cons of solar power
- very expensive to buy
- cheap to run = pro
- lots of energy is needed to be useful
A solar power tower
-uses thousands of mirrors to reflect the sun’s rays to a big water tank at the top of the tower
Solar power tower way of working
- mirrors surround the base of the tower (water tank on top)
- sun’s rays become directed at the tank = heats it
- creates steam = electricity
solar power tower pro
-mirrors are controlled by the computer to track the sun = effective
geothermal energy meaning
- comes from the energy released by radioactive substances
- deep within earth
