P3- energy resources

Question 1

what are fossils fuels

Answer 1

Fossil fuels = coal, oil and gas

Question 2

how are fossils fuels made?

Answer 2

Living organisms millions and millions of years ago died, and they became buried in the earth. Under a lot of heat and pressure, they became fossil fuels.

Question 3

what happens when fossils fuels are burned

Question 4

Fossil and nuclear fuels are non _______/_______

Answer 4

sustainable/renewable

Question 5

what does non-renewable mean

Answer 5

Non-renewable = they can’t be replaced. This means we are using things faster than they are being made

Question 6

how is energy generated in most coal/fossil powered station

Answer 6

In most gas/coal-fired stations (power plants), the fuel is burnt –> this heats water in a boiler –> this causes the water to become steam –> the steam rises to drive the turbine and turn the generator –> generates electricity

Question 7

where can we get methane from

Answer 7

Methane is one of the gases we get from crude oil, HOWEVER there are also some natural sources of methane:
1) cow/animal manure
2) sewage works
3) decaying rubbish (landfill

Question 8

what does Bio-fuel mean

Answer 8

Biofuel = fuel taken from living/recently living organisms

Question 9

where does nuclear fuel take energy from

Answer 9

Nuclear fuel takes energy from atoms

Question 9

what are 2 positives of bio-fuel

Answer 9

2 positives of biofuel: renewable and carbon neutral

Question 10

what are the fuels in nuclear power stations

Answer 10

Fuel in nuclear power station = uranium or plutonium (radioactive isotopes so can be used as fuel)

Question 11

why is uranium and plutonium radioactive

Answer 11

they are radioactive as the nucleus of the uranium atom is unstable, and so it can be split in two

Question 11

what happens when there are lots of atoms in the core

Answer 11

When there are lots of atoms in the core it will get very hot

Question 12

why is nuclear energy better than fossil fuels

Answer 12

Energy released by a kg nuclear fuel is 10,000x the energy released by a kg of fossil fuel

Question 13

what are disadvantages of wind generator

Answer 13

DISADVANATGE: Unreliable - when there is little or no wind, no electricity is generated

Question 14

how does wave energy work

Answer 14

Wave energy: waves make a floating generator move up and down –> motion turns the generator which generates electricity

Question 15

disadvantage of wave energy

Answer 15

DISADV: 1. generators need to withstand storms and they don’t constant supply of energy
2. Requires a lot of maintenance and resources - lots of cables and buildings need to connect the generator to the grid
3. Visual pollution - spoils areas of coastline

Question 16

what is ‘HEP’

Answer 16

HEP = Hydroelectric power

Question 17

where is rain water collected?

Answer 17

Rainwater is collected in a resevoir (or water in a pumped storage scheme), which flows downhill

Question 18

what drive the turbine and turns the generator in a reservoir

Answer 18

When this water is falling downwards, it drives the turbine which turns the generator

Question 19

what can suns energy produce/generate

Answer 19

Sun’s energy can:
generate energy using solar cells
heats water directly in solar heating

Question 20

why is solar energy not as useful for powering big things

Answer 20

Solar cells convert less than 10% of the energy they absorb into energy transferred by electricity

Question 21

where are some example of where solar cells can be found

Answer 21

watches, calculators

Question 22

why us sun energy not as reliable

Answer 22

Solar cells convert less than 10% of the energy they absorb into energy transferred by electricity
HOWEVER a LOT of solar energy is needed to create enough electricity to be useful
Unreliable where sun is often hidden behind the clouds

Question 23

how does a solar cell work

Answer 23

A solar heating panel heats water that flows through it Water in the tank is turned to steam by the heating effect of the solar radiation directed at the water tank Steam is piped down to the generator where it makes electricity

Question 24

what does geothermal energy mean

Answer 24

Geothermal energy: geo = earth thermal=heat

Question 25

how does geothermal energy produce energy

Answer 25

Geothermal energy --> uses energy released by radioactive substances deep within the earth

Question 26

how does geothermal energy work

Answer 26

Power stations are built in volcanic areas or places where there are hot rocks underneath Water is pumped down to these hot rocks --> heat turns the water to steam --> steam rises --> drives the turbines which turns the generator

Question 27

what are fossil fuels and what are some examples

Answer 27

fossils fuels are the gases that get trapped in the earths atmosphere. For example, CO2, methane, water vapours

Question 28

what causes climate change

Answer 28

Scientists believe the increase in greenhouse gases is the reason for global warming and climate change

Question 29

why is burning fossil fuels bad?

Answer 29

Burning fossil fuel --> sulfur impurities in the fossil fuels means that when fossil fuels are burned, sulfur dioxide is released --> causes acid rain --> sulfur dioxide can be removed from the flue gases by lining the chimeny with calcium carbonate (limestone)

Question 30

what are some advantages of nuclear energy 2 points

Answer 30

Advantages of nuclear energy: 1)No greenhouse gases/carbon emissions 2)Much more energy is transferred a kg of uranium or plutonium compared to a kg of fossil fuel

Question 31

what are disadvantages of nuclear energy

Answer 31

Disadvantages: 1)Fuels rods have radioactive waste --> has to be stored safely for centuries 2)Nuclear reactions are normally safe but an explosion would release radioactive waste over wide area --> affects people for many years-eg. Chernobyl 3)Expensive 4)High maintenance

Question 32

renewable sources advantages 4 points

Answer 32

Renewable Sources Adv: 1)Never runs out --> always being replenished by natural resources 2)Don’t produce greenhouse gases/carbon emissions or acid rain 3)No radioactive waste products 4)Can be used where connection to the national grid is uneconomical

Question 33

renewable sources disadvantages

Answer 33

Not able to meet the world’s energy demands Wind turbine - sound pollution Tidal barrages affect habitats HEP needs large resevoirs - affects habitats --> habitats are often flooded for dams Solar cells need a large surface area to create a lot of electricity Some are unreliable --> not available all the time

Question 34

WHICH SEASON IS ENERGY DEMANDS HIGHEST

Answer 34

Energy demand is higher in winter than summer

Question 34

why can renewable energy be unreliable

Answer 34

Renewable energy - very unreliable - very dependent on certain specific conditions - you can’t obtain energy on demand, the way it is required in winter

Question 35

what is required to run a facility

Answer 35

Overall cost of new facility includes: Capital costs to build - cost/kW of power Capital costs to take it out of use Running cost --> fuel + maintenance Capital costs are lowest for gas-fired stations and highest for nuclear and wind

Question 36

what are four demands that variable demands are met by

Answer 36

Variable demand is met by: Nuclear and coal-fired stations to provide constant energy - base load demand gas-fired stations and pumped storage schemes for daily and seasonal variations Renewable energy for high demand when the conditions are right (windy for wind energy) Renewable energy when low demand to store in pumped storage schemes