Energy booklet Flashcards
impact of coal mining
habitat lose, noise, dust, turbid or acid drainage water, spoil heaps
impact of oil extraction
marine seismic surveys disturbs whales, land seismic surveyors lead to habitat destruction by being bulldozed, oil spills
impact of fuel processing eg coal washing
coal is washed with water to remove chemicals and impurities before combusted - creates coal slurry, stored in ponds that can leak or spill, increasing turbidity of water and release toxic metals eg mercury
impact of fuel processing eg oil refining
gaseous emissions eg carbon dioxide, NOx, particulates and hydrocarbon vapours are produced
impact of equipment manufacture
any equipment used to harness energy will cause habitat loss from material extraction and pollution from manufacture eg metals, concrete, plastics
what are the main impacts of resource exploitation
pollution, atmospheric pollution (caused by fossil fuels) ash, oil pollution, radioactive waste, noise pollution, thermal pollution, habitat damage
what are the main causes of habitat destruction during resource exploitation
fuel extraction eg open cast mining, power station and equipment location eg wind turbines, pipelines and cables eg digging the ground to lay them
disadvantages of using wind turbines
need to be spread over a large area (habitat destruction) noise is stressful to wildlife, bird strikes, bat lungs explode due to low pressure zone around turbine
what is a tidal power scheme
captures energy from tides, dams trap water trap water at high tides and release it through defined channels that carry it through a turbine
what are 5 ecological impacts of tidal power schemes
mining- for construction, reduced tidal range, fish barrier, pollutants build up behind the barrage, sedimentation- areas of slower flow sediment begins to settle
explain the affect of the ecological impact of tidal power schemes; reduced tidal range
restricted flow through barrage reduces tidal range behind the barrage - high tides not as high low tides not as low - areas near high tide mark would dry out and marks of low tide would never be uncovered, reducing mudflat feeding areas for birds
explain the affect of the ecological impact of tidal power schemes; sedimentation
water flow in and out of lagoon behind the barrage is only possible through the channels, so there are areas of very fast flow where sediment is eroded, in other areas of slow flow sediments deposit and build up and, also due to extended periods of static water at low and high tide, sediment settles and general turbidity is lower. light can penetrate deep water, increasing temperature allowing more photosynthetic organisms to survive
name 2 ecological impacts of hydro electric power schemes (HEP)
flooding of previous terrestrial habitats, changes in the river
how does a constant flow in a HEP impact the environment
dry season sandbanks used by birds and turtles are lost, high flow periods lost so sediment builds up losing gravel fish spawning sites, height of river level downstream stops seasonal flooding which may be essential for plants breeding fish and other aquatic animals
how does a sudden flow increase in a HEP impact the environment
increased turbidity makes it difficult for fish eating birds to see their food, reduced light penetration makes photosynthesis by aquatic plants more difficult, species that cannot resist high flow rates may be washed away
what is a resource
all material theoretically available for exploitation, including deposits that cannot be exploited
what is a reserve
all materials that can be exploited now, economically, using existing technology
what are the three main ways of extracting oil from the ground
primary oil recovery (best) , secondary oil recovery and tertiary oil recovery
what is primary oil recovery
crude oil contains natural gas so the oil rushes to the surface under it’s natural pressure
how can primary oil recovery go wrong
an oil rig blowout
what is secondary oil recovery
the extraction fo crude oil where the pressure is maintained by pumping water or natural gas into the reservoir
what is tertiary oil recovery
the extraction of crude oil where the viscosity of the oil is reduced using methods such as injecting steam, solvents or bacteria
what is the advantage of directional drilling as an improvement of oil recovery
many wells can be drilled from a single platform, you can drill underneath locations where drilling rigs couldn’t be placed, can follow weaker or softer rock to make drilling quicker and target small reservoirs - significantly increasing total recovery rates
how can oil shale be extracted
mining the rock and then heating it or heating the oil shale underground and then piping up the liquid oil
how to tar sands work
the sand is mined and mixed with hot water. the oil floats to the top and can be removed before refining
what are the disadvantages of oil shales and tar sands
duet to mining and complex processing there’s a huge energy input and thus a huge carbon footprint
what is CCS
carbon capture storage, pumping waste carbon dioxide from industry underground for storage in an attempt to reduce global climate change
how is CCS a specialised form of secondary oil recovery
the carbon dioxide underground builds up pressure that can force nearby crude oil to the surface
why do we need hydraulic fracturing
large volumes of crude oil and natural gas are trapped in pore spaces in shale rock that have low permeability, so by opening fissures in surrounding rock oil and natural gas can flow towards a recovery well
what is hydraulic fracturing made of and how do they contribute
high pressure fluid made of water, sand and various chemicals - sand stops the fissures closing up
name some concerns about fracking
setting of small earthquakes, fracking chemicals natural gas or toxic metals from rock contaminate aquifer water, and the huge volume of water needed for the process
what is underground coal gasification
coal too deep or fragmented is burnt underground by pumping air to provide oxygen and steam for heat, which produces a mixture of combustible fuels eg hydrogen and methane that can be piped up the the surface
what is a disadvantage to underground coal gasification and how is it dealt with
it has a waste product go carbon dioxide but this can be pumped back into the ground as part of CCS
what happens if you have too much or too little oxygen whilst performing UCG
too much- hydrogen and methane become useless carbon dioxide and water, too little- and the coal won’t ignite
what is coal liquefaction
conversion of coal to liquid hydrocarbons which have applications that solid coal cannot perform eg liquid vehicle fuels
how is coal liquefaction performed
converting liquids directly using solvents or indirectly using gasification then chemical changes to convert carbon monoxide and hydrogen to hydrocarbons
what are methane hydrates
solid ice-like chemical deposits formed from methane and water in cold, high-pressure, deep ocean sediments
how is methane removed from the methane sediments
melted out with hot water, ‘sucked’ out using a pump to create low pressure in the pipe or displaced using carbon dioxide. then pumped to shore in pipes and combusted as a fuel
what is polymer adsorption
uranium dissolved in seawater adsorbs onto certain polymers that are placed in the sea. uranium can then be washed off using acid then collected and concentrated
which is the desired isotope of uranium
U-235 (92 protons + 143 neutrons)
what is nuclear fission
the splitting of an atom through a chain whereby neutrons split
what is nuclear fission used for
a form of energy, where the heat energy produced is during the fission chain reaction boils water to steam which turns a turbine, attached to a generator
what’s a disadvantage to using the U-235 isotope in nuclear fission
they’re extremely radioactive and require special disposal
what’s the difference between fresh nuclear fuel and spent (used) fuel
fresh isn’t actually that radioactive and can be handled with gloves, used is so deadly it has to be handled by robots
what is phosphate mining
uranium is often present in phosphate deposits and can be separated from the material extracted in phosphate mines
what is coal ash
uranium can be extracted from coal ash. this will become economic if the price of uranium rises enough
what is the non-fissile isotope called
U-238
what is a plutonium reactor
U-238 makes up most of the bulk of uranium placed in nuclear fission reactor, but during the U-235 chain reaction, some neutrons will bombard U-238 and convert it to plutonium-239
what does plutonium-239 do
be used for electricity production
what is a fertile fuel
non-fissile isotope, such as U-238, that can be converted into a fissile fuel
what is the name of the reactor that is designed to produce more P-239
fast breeder reactor (FBRs)
what is a fast breeder reactor
nuclear fission reactor that contains U-235 and U-238 that produces so much P-239 they end up with more fissile fuel than they started with
what is the disadvantage to fast breeder reactors
they’re extremely complex and expensive, never really became popular as more uranium reserves were found and improve uranium enrichment reduced fuel cost
what is shale gas extraction
an example of hydraulic fracturing where water, sand and chemicals are injected into the well to create fissures and gas can flow out
how is plutonium-230 produced
U-238 absorbs a neutron to become U-239, this is a beta emitter, and decays to produce neptunium-239, np-239 decays to produce plutonium-230
what does thorium-232 do
it’s another non-fissile fuel, that can be bombarded with neutrons to breed into U-233, which is fissile.
what is U-233 used for
it’s purified to create fuel rods for electricity production
name 3 advantages of thorium reactors
there’s 3 more thorium in the earth’s crust than uranium, there’s less radioactive waste and the waste has a shorter half life, there is no U-238 present so no P-239 can be produced so thorium reactors are less useful for nuclear weapon production
name 3 disadvantages of thorium reactors
breeding rate of uranium-233 is slow so fuel is expensive, uranium-233 releases alpha radiation so it’s very hazardous, it’s less-developed technology that uranium reactors so production cost is still high
what is nuclear fusion
a type of nuclear power that involves the joining of the nuclei of small atoms eg H2 and H3, with the release of a substantial amount of energy that could heat water to steam for electricity to generate
what does deuterium hydrogen + tritium hydrogen =
helium + neutron + energy
where do you get H-2 and H-3 from
H-2 is extracted from water and H-3 i produced by bombarding lithium with neutrons
what 4 conditions are needed for fusion to occur
hydrogen in the form of plasma, a heavy nuclei, a very high temperature and a vacuum
why do you need hydrogen in the form of plasma for fusion
the repelling negatively charged electrons around the nuclei must be removed so the nuclei can collide
why do you need a heavy nuclei for fusion
greater mass means greater momentum so are more likely to overcome the repelling positive nuclei
why do you need a very high temperature for fusion
to increase the kinetic energy of the nuclei and increase the chance of nuclei colliding
why does nuclear fusion require a vacuum
sinnce hydrogen nuclei colliding with air will slow the H nuclei down, cooling the plasma reducing fusion success
why is a magnetic field needed for fusion
to stop the H nuclei colliding with the sides of the reactor, which will slow the H nuclei down, cooling plasma and reducing success
what are the two main techniques of nuclear fusion
toroidal reactors and laser fusion
what are toroidal reactors
nuclear fusion reactor in which hydrogen plasma is held in a chamber surrounded by magnetic coils in a torus, injecting fuel and leaving into a boiler
what is laser fusion
a small sphere of H-2/H-3 is bombarded with laser beams , the hot outer layer expands in all discretions including inwards compressing the middle, fusion starts in the compressed middle, spreading throughout the sphere releasing much more energy than was used in heating
name 3 renewable energy technologies
solar, hydroelectric and wind
how does photothermal solar power work
cold water runs along a thermostatically controlled pump, with demineralised water, into a black pipe filled with water, and an incident solar radiation at 90degrees to the panel and a sheet of glass (produces a greenhouse effect) out comes hot water which goes into a heat exchanger
what is a heat pump
transfers heat energy from a source of heat to a destination called a ‘heat sink’, heat source is at ground depth where the temp is fairly constant all year around - indirect photo thermal power beaches the ground was heated by the sun
how does a heat pump work
ground loop, pipes buried in the ground, transfers heat to a working fluid in the heat pump, at the expansion valve the working fluid expands causing it to cool, at the compressor increasing the pressure raises the vapour temperature, distribution system is underfloor heating or radiators and heat is transferred to this
name all types of solar power
photothermal solar power heat pumps photovoltaic solar power multi-junction photovoltaic cells anti-reflective surfaces Concentrating Solar Power (CSP).
how does a photovoltaic solar power work
converts light energy directly into electricity
name 3 effective photovoltaic solar powers
crystalline silicon cells- higher efficiency than amphorus silicon cells, anti-reflective textured surfaces- reduce reflection of sunlight thus increasing absorption, multi-junction photovoltaic cells, multiple layers of different non-silicon, absorb different wavelengths of light so greater amount of available light is absorbed and converted to electricity
how is light from parabolic reflectors used
light is absorbed by tubes of oil used to heat molten salt in stored large insulated tanks. salt is heated up to 550degrees which boils water and drives team turbines when electricity is required
name 2 types of concentrating solar power
parabolic reflectors and solar power towers
how do solar power towers work
use mirrors to reflect sunlight onto a receiver on a tower which contains molten salt for steam generation to power turbines
what are the two generators of hydroelectric power
low head turbines and helical turbines
