Energy Respurces

Question 1

New reactor designs

Answer 1

Molten salt-molten salt as a reactor collect increases efficiency as can increase temp
Plutonium-99% of unranium can be comvertied into fiddle by plutonium
Thorium-can be converted into uranium which releases energy

Question 2

Uses of hydrogen

Answer 2

Combustion for heat
Fuel cells- combination of H and O to produce H2O and energy

Question 3

Causes for Per capita energy consumption to change per country

Answer 3

Affluence - higher income means people can buy more and use more energy

Relative cost of energy-determines weather energy is cheaper due to location(local) and accessibility

Type of industry:
-primary, (mining) high energy use
-secondary (metal smelting) medium
-tertiary, (finance) low
-quaternary (IT) very low

Climate-climate consolation affect energy usage as building in locations in cold winter may use more energy for heating

Question 4

Features of energy resources

Answer 4

Renewable/non-renewable

Depletable/non-depletable

Abundance-fossil fuels deep underground cannot be extracted

Locational constraints-areas could be SSSI

Intermittency-energy could be be available when needed

Predictability

Energy density-higher energy density are more useful

Resource availability

Ease of storage

Ease of transportation

Question 5

Sustainablilty of current energy use

Answer 5

Resource depletion-fossil fuels provide most global energy but will deplete.

Economic sustainability-depleted non-renewables will become more expensive

Environmental impacts

Question 6

Features of fossil fuels

Answer 6

Chemical energy- easy to convert to heat energy and easy to store

Energy density-fossil fuels are very energy dense so small mass can do a lot

Finite resources-will eventually be depleted

Available resource-some oil/coal might not be exploitable as they are to deep. It’s not economically viable
May cause pollution.
May cause habitat damage

Question 7

Extraction methods and environmental impacts of coal and oil+gas

Answer 7

Coal:
-Deep mining(labour intensive and expensive) and open cast(coal must be close to the surface).
-environmental damage caused by deep mining is usually at the surface (loss of habitat). Open cast is worse for the environment (more damage)

Oil+gas:
-oil in liquid form flows through permeable rock and is collects in porous rocks. A pipe is drilled down and the oils will be forced out.
-oil spills can occur and cause pollution
-surplus gas on rigs may be burnt to reduce the risk of explosions, this causes atmospheric pollution (CO2 and sulfur dioxide)
-gas is extracted by the same ways as oil

Question 8

Uses of fossil fuels (crude oil, natural gas, coal)

Answer 8

Crude oil:
Fuels vehicles, gas for heating, plastics

Natural gas:
Heating(domestic and industrial)
Electricity

Coal:
Electricity, iron and steel industry

Question 9

New fossil fuel tech (coal)

Answer 9

Coal:
Coal gasification-coal is to deep to be mined but can be burnt underground to produce fuel gases (H,CO,methane)
Coal liquefaction-conversion of coal to liquid hydrocarbons which have applications that solid coal cannot perform (vehicle fuel)

Question 10

New fossil fuel tech

Answer 10

Oils:
Primary oil recovery-uses natural presence of water below the oil or gas that is presented above it. This pressure forces oil up the production well to the surface (20% of the oil can be extracted)

Secondary oil recovery-pumps water or natural gas down an injection well to maintain pressure (recovery rate about 40% now)

Tertiary oil recovery- reducing the viscosity for increase the recovery
-steam pumped down to heat the oil
(Recovery now at 60%)

Directional drilling - allows well to be drilled that aren’t vertical.
Many well can be drilled from a single platform
It’s possible to drill underneath locations where rigs couldn’t be placed (city’s)

ROVs and AUVs- remotely operated vehicles and autonomous unmanned vehicles can be used to inspect underwater production

Fracking-uses high pressure to open fissures in surrounding shale rock.
Confers over fracking:
-natural gas may enter aquifers
-chemicals underground may cause pollution
-toxic metals may become mobile

Question 11

New tech (gas)

Answer 11

Enhanced gas recovery-injection of CO2 or N maintains pressure and allows gas to be recovered

Fracking

Methane hydrate-it’s not exploited but potentially yield more methane that conventional natural gas sources.
Water heating- hot water pumped on the crystals(methane hydrate), they melt releasing the methane.
Depressurisation-drilling into the sediments causes the pressure to drop, the methane will gradually leave the crystals

Carbon capture and storage

Question 12

What is nuclear fission

Answer 12

A neutron hits a large atom, this causes it to split into two new atoms “fission products” and releases new neutrons which causes a knock on effect

Question 13

Main features of fission

Answer 13

Very high energy density- 1kg of uranium is worth 13 tonnes of coal

Embodied energy- process to produce the fuel and complexity of nuclear power stations require a lot of energy

Finite resources- uranium is non-renewable, currently lots of uranium cannot be economically extracted.

Level of technological development-
Longer reactor life(60+ years instead of 40*)
More reliable
Lower fuel consumption

Environmental impacts
Habitat loss, noise, dust, turbid drainage water, hazardous wastes- from mining
Contribution to global climate change- high embodied energy
Health risks(ionising radiation)- reactor accidents + radioactive waste

Question 14

New tech for uranium extraction

Answer 14

Polymer adsorption-U dissolved in seawater adsorbs onto polymers placed in the sea, the U can be washed of using acids, then collected and concentrated

Phosphate mining - U is separate from phosphate deposits

Coal ash- U extracted from coal ash

Question 15

Thorium reactors explanation,
Pros and cons

Answer 15

Thorium isn’t fissile so dosent release energy when hit with neutrons, however it’s a fertile fuel and can be converted into U-233 which can be hit with Neutrons releasing energy

+3x more abundant than U
Much more difficult to make weapons
Much less radioactive waste is produced (and shorter half life’s)

• the breeding from U-233 is slow so it’s expensive
  U-233 releases A radiation so very hazardous
  Cost for development is high(new tech)

Question 16

What is nuclear fusion?

Answer 16

Joining of the nuclei of small atoms(such as isotopes of H) releasing energy

Question 17

Conditions for fusion to occur

Answer 17

H in the form of plasma
Heavy nuclei
Very high temp
Vacuum
Magnetic field

Question 18

Benefits of toroidal reactors

Answer 18

Releases more energy than uses
(50MW input - 500MW output)

Maintains fusion for longer periods

Uses a blanket of lithium to breed new tritium fuel

Question 19

Properties of renewable energy resources

Answer 19

Intermittency- solar isn’t available during night

Predictability-wind can’t be predicted accurately

Energy density

Ease of storage

Environmental impacts

Geographical constraints

Size of available resource

Level of tech development- many renewable tech isn’t fully developed

Economic issues

Question 20

Solar power properties

Answer 20

Local constraints-can’t be used where no sun

Problematic properties:
-intermittency
-reliability
-energy density (low)

Question 21

Harnessing solar power

Answer 21

-Photo-thermal solar power-absorb sunlight to produce heat for hot water or heating

-passive solar architecture-builds can be designed to maximise the adsorption of sunlight for heating

-heat pumps - uses the change of state from a liquid to a gas to absorb heat from the environment

-photovoltaic (PV) solar power-when PV absorbs photons of light electrons are dislodged from atoms, these from along an electrical conductor from this electrically negative layer to a positive layer. This provides current to power electric appliances

Question 22

Environmental impacts of solar power

Answer 22

Manufacture-requires extraction of minerals (metals,plastics). Making PV solar panels produces toxic wastes (small amounts of carom)

Impacts during use-need to be cleaned which requires water which may be scarce in the areas suited to solar panels

Question 23

New solar power tech

Answer 23

Anti-reflective surface-having textured surface increases absorption

Transparent PV cells-PV cells that let most light through can be used as windows

Self cleaning panels- nanohydrophic surfaces

Question 24

Local restraints on HEP

Answer 24

Large water catchment area

High total rainfall(distributed evenly through the year)

Low water turbidity

Impermeable bedrock below the reservoir

Close to consumers

Suitable topography- narrow exits to a large basin

Question 25

Environmental impacts on HEP

Answer 25

Reservoir creation- require large amounts of mats, the extraction of them require a lot of energy. Loss of habitat when it floods. Decomposition of DOM can create anaerobic conditions and the release of methane gas Impacts on the river-sedimentation can reduce turbidity and replenish the nutrients onto the flood plains around the rivers

Question 26

New HEP tech

Answer 26

Low head turbines: -waterwheels- less efficient but don’t suffer from screen blockages with leaves and litter -Kaplan turbines-blades that can be rotated to allow for variation in river flow (can harness 90%) -helical turbines-they are turned by water running through them(high efficiency and turbidity dosent matter, fish can go through without being harmed)

Question 27

Harnessing wind power

Answer 27

HWAT +tech is more developed and has a higher efficiency -stress cracking can occur, tall towers are needed VWAT +turbines driven from wind in any direction, quieter than HWATS, operate at lower wind speeds -no large VWATS built, lower efficiency

Question 28

Local constraints of wind power

Answer 28

Wind velocity (costal areas) Isolation-small scale wind farms can provide for small rural towns Land use conflicts: Ecological-need to be located away from migration roots of birds, high bat populations Land req-requires a large land Telecommunication interference-can interfere with radon and radar systems

Question 29

Environmental impacts of wind power

Answer 29

Manufacture and instillation-production of materials and transportation Noise-if you like close to them they may become irritating Habitat damage - habitat is destroy at the ground Bird strikes-have the power to kill birds Bat deaths- change in air pressure caused by the blades can kill bats

Question 30

New wind power tech

Answer 30

Blade-tip fins - reduce turbulence and wind resistance, increasing efficiency Helical VWAT blades- rotates smoother and increases efficiency, decreases chance of stress fracture

Question 31

Harassing wave power

Answer 31

Point absorber - have floating structure which rises and falls, turning an generator Overtopping/terminator device- water falls into storage reservoir above sea level ( due to crashing of waves) this then passes through a turbine and back into the sea Surface attenuator waver power-floating device, when waves pass the push and pull pistons which forced fluid through a turbine

Question 32

Harnessing biofuels

Answer 32

Wood Alcohol from carbohydrate crops (sugar cane) Biodiesel from vegetable oils (sunflower oil) Methane from anaerobic digestion (sewage) Combustible crop(straw)

Question 33

+ and - of biofuels

Answer 33

+supply rate can’t be controlled Can be sorted until needed (supply and demand) “Carbon neutral” - releases the same about of C and absorbed Energy density of alcohol and biodiesel is almost as high as fossil fuels -large areas of farmland req Energy density of straw and wood is lower to that of fossil fuels Intensive farming tech to produce biofuels could produce as much CO2 as fossil fuels

Question 34

New biofuel tech

Answer 34

Hydrogen from algae -some algae produce H, which can be used as fuel Anaerobic digestion - methane

Question 35

Harnessing geothermal power

Answer 35

Low temp schemes: -geothermal springs-ground water heated by hot rocks -geothermal aquifers- hot groundwater pumped to the surface High temp schemes: -geothermal steam systems-ground water at very high temps may be brought to the surface using boreholes, using the steam to generate electricity -hot dry rock systems-water pumped onto the rocks, and steam is recovered up another borehole

Question 36

Environmental impacts of geothermal power

Answer 36

Infrastructure-pipes and boreholes can be obstacles for mammals Gaseous emissions-the hot water extracted from the ground can release small amounts of CO2 and H sulfide Waste water- contains heavy metals and salts

Question 37

New geo tech

Answer 37

Low temp fluids-using liquids with lower temps means that we would be able to use more areas with lower rock temps (ex, butane or pentane)

Question 38

Harnessing tidal power

Answer 38

Tidal barrages- a dam across an estuary where turbines are located so when water flows in or out of an lake turbine rotates Tidal lagoons- surrounds a part of an estuary or bay. Water can be pumped in causing electricity to be generated In- stream turbines - fix to the sea bed and absorb the kinetic energy

Question 39

+ and - of tidal power

Answer 39

+tides are predictable(sun and moon) Tidal barrage in large estuary will have a large energy output -intermittency Few suitable sites for construction of a barrage Large environmental impacts

Question 40

Environmental impacts of tidal power

Answer 40

Tidal barrages: -mats- large quantities on mats, extraction, processing and transporting -tidal range change-reduces ease at which water can flow in or out of lagoon -sedimentation-sediments will settles and build up, light can penetrate further so more photosynthesis and higher temps means of water Tidal lagoons-same impacts but smaller scale In-stream turbines -don’t block natural tide flow, produce noise (could affect whales/dolphins)

Question 41

What is a fuel cell

Answer 41

Electrochemical cells which store energy in chemicals (H/alcohols), if there is fuel then they can always produce energy, the simplest types use O and H as fuel

Question 42

How is H stored

Answer 42

Compressed gas Liquid - high pressure and very low temps Metal hydride systems- H adsorbed onto the surface of metal Ammonia

Question 43

Causes of fluctuations in energy supply

Answer 43

Use of intermittent sources Bulk delivery

Question 44

Causes in fluctuation in demand of energy

Answer 44

Seasonal fluctuations Weekday/weekend fluctuation Fluctuation on demand (TV breaks)

Question 45

Factors affecting rechargeable battery viability

Answer 45

Efficiency of storage cycle Energy density Cost per unit of energy stored Recharge speed

Question 46

Types of storage systems

Answer 46

Vehicle to grid systems (V2G) -vehicles plug into the grid when parked for long periods of time, a small portion of energy from the battery will be taken out to supply the grid Molten salt- thermal storage, Kinetic energy - flywheels are a temporary storage.

Question 47

Vehicle designs to reduce energy loss

Answer 47

Aerodynamics-reduce friction Regenerative breaking systems-use a generator to convert the kinetic energy to electricity (stored as chemical energy in the battery) Reduced mass-reducing the fuel consumption, higher energy density batteries, using plastics instead of metal where it isn’t needed, replacing cast iron engine blocks with lighter aluminium ones Wheel design-less energy loss using solid wheels but they give a bumpy ride (unless trains-rails) Fuel combustion efficiency-using a fan to keep engine running at optimum temp, efficient waste gas removal so it dosent mix with the new fuel Vehicle design for life-use of recyclable materials, easy dismantling, reusable components

Question 49

Building designs to reduce energy loss

Answer 49

Orientation- solar gains through windows can increase temp / reduce heating Building SA- large SA: V = lots of heat lost

Question 50

Materials to reduce energy loss for buildings

Answer 50

High thermal mass mats- reduce temp extremes Low embodied energy mats- (limecrete>concrete, rammed earth>concrete block walls)

Question 51

Heat conservation methods

Answer 51

Low thermal conductivity- insulation roof, walls and floor Reduce convection- double glazing windows creates a layer of static air that is to narrow for a convection to occur Reduced warm air loss- draught proofing seals around doors and window openings

Question 52

Ventilation methods

Answer 52

Heat recovery during ventilation- heat exchangers used to reduce heat losses (counter current flow) Automatic ventilation - large glazed areas increase solar gains

Question 53

Energy management tech

Answer 53

Occupancy sensors - detect source of infrared energy, turn appliances when no sources detected Programmable thermostats- easy to adjust the heat of a large no. Of rooms and avoid energy wasted by unnecessary heating

Question 54

Low energy appliances and how their reduced

Answer 54

Lightbulbs - LEDs Washing machines- low energy machines have faster spin cycle, cold wash cycles Dish washer-newer dish washers use less water

Question 55

How can humans reduce energy loss in homes

Answer 55

Turning of lights Turing down thermostats Turning appliances of rather than leaving them on

Question 56

Industrial energy conservation

Answer 56

Heat- using long narrow pipes (with a food conductor like copper ) to increase SA Insulation- reducing heat losses, so less heat needed High volume storage - reducing SA by using a large tank rather than multiple small ones Combined heat a power (CHP)- recovers lots of heat lost in electricity generation, used for heating

Question 57

Electricity infrastructure management

Answer 57

Peak shaving (HEP) - storage is surplus energy to be used when demand raises High voltage grid - having a high current on cables to reduce energy losses in heat (PD)