P3 - Energy Resources

Question 1

What is the defenition of renewable energy?

Answer 1

Energy from a source that is not depleted when used.

Question 2

What is the definition of sustainable energy?

Answer 2

Energy that will not compromise future generations to meet their energy needs.

Question 3

How is electricity generated from hydroelectricity?

Answer 3

1. water stored behind dam (GPE)
2. water turns turbine (GPE to kinetic energy), flows
3. turbine connected to generator (kinetic energy to electrical energy)

GPE - gravitational potential energy

Question 4

What are the pros of hydroelectricity?

Answer 4

• reliable
• no pollution
• water can be stored for high energy demands
• lasts decades
• tourism

Question 5

What are the cons of hydroelectricity?

Answer 5

• Expensive to build
• no profit for decades
• natural habitats destroyed
• floods large areas

Question 6

How is energy generated from tidal power?

Answer 6

1. water stored behind barrage (GPE)
2. water turns turbine (GPE to kinetic energy), flows to area with less water
3. turbine connected to generator (kinetic energy to electrical energy)

Question 7

What are the pros of tidal power?

Answer 7

• no pollution
• predictable energy outputs (predict tides)
• infinite resource
• low maintenance cost

Question 8

What are the cons of tidal power?

Answer 8

• expensive to build
• few ideal locations
• disrupts sea life

Question 9

What are the requirements to build tidal power stations?

Answer 9

• must be on coastlines
• atleast 5m water height change in tides

Question 10

How is coal formed? (4 marks)

Answer 10

1. millions of years ago, animals died and sank to ocean floors
2. covered in sediment that turned them into sedimentary rock
3. pressure and temperature build up
4. transformed remains into crude oil and natural gas

Question 11

How do wind turbines generate power?

Answer 11

1. wind turns turbine - rotates a shaft at around 18rpm (kinetic energy)
2. the rpm can be increased by using cogs to around 1800rpm
3. the shaft is then connected to a generator which converts the kinetic energy to electrical energy

rpm - revolutions per minute

Question 12

What are solar cells?

photovoltaic (PV) cells

Answer 12

electronic devices that can directly convert light to electricity

Question 13

What are solar cells used for?

Answer 13

small devices such as watches and calculators

Question 14

What is a solar panel?

Answer 14

solar cells that are connected

Question 15

What is a solar heating panel?

Answer 15

heats water that flows through it

Question 16

How does a solar tower generate electricity?

Answer 16

1. mirrors (computer controlled) reflect light onto a large water tank
2. the water is heated up and transforms into steam
3. the steam is piped down and turns a turbine

Question 17

How is electricity generated from geothermal energy?

Answer 17

1. cold water is pumped down to hot rocks beneath the surface
2. the water is heated up and transforms into steam
3. the steam is piped back up and turns a turbine

Question 18

What is the source of geothermal energy?

Answer 18

energy released by radioactive substances deep within the Earth