3.3.4
Cards (29)
- improves fossil fuel technology
- secondary/ tertiary oil recovery
- directional drilling
- oil sands
- carbon capture and storage
- hydraulic fracturing
- coal gasification
- coal liquification
- methane hydrates
- improved nuclear power- fission
- plutonium reactors
- thorium reactors
- molten salt reactors
- improved uranium extraction techniques
- improved solar technology
- self- cleaning pannels
- anti-reflective surfaces
- multi-junction PV cells
- transparant PV cells
- heliostats
- PV/ thermal hybrid system
- concentrating solar power
- improved HEP
- low head turbines
- helical turbines
- improved wind power
- helical VAWT blades
- direct drive turbines
- VAWTS
- lighter blades
- larger rotor diameter
- wind assisted ships
- bird and bat deterrents
- improved biofuel
- hydrogen from algae
- anaerobic digestion
- improved geothermal technology
- low temperature fluids
- district heating systems
- improved tidal power
- tidal reef scheme
- causes in fluctuation of energy demand
- weather
- 24 hr work fluctuation
- seasonal fluctuation
- weekday/ weekend fluctuation
- short term- tv, mealtimes
- energy storage technology
- peak shaving using pumped-storage HEP
- rechargeable batteries
- compressed gas
- fuel cells
- thermal storage
- vehicle to grid (V2G) systems
- power to gas (P2G) systems
- the hydrogen economy
- what is peak shaving using pumped- storage HEP?surplus electricity pumps water uphill, storing it as GPE. This can be converted back to electricity through the kinetic energy of letting the water flow back to a lower level through a turbine to meet peak energy demands.
- what is compressed gas?surplus energy drives a pump to compress gas that can be stored underground in tanks. The gas can be released later to power machinery. The heat produced from compression can also be stored e.g in molten salt storage.
- what is vehicle to grid systems?energy is transferred between the national electricity grid and vehicle batteries when cars are parked for long periods of time. This enables a small proportion of energy is vehicle batteries to be used in peak demand.
- what is power to gas systems?surplus electricity is used to produce gaseous fuel that can be stored. water is electrolysed to produce hydrogen and fed into national gas pipes as methane.
- how is hydrogen used to release energy?-combustion to produce heat- used domestically or creates stream to drive a turbine to produce electricity-fuel cells- electrochemical process combines oxygen and hydrogen to produce water, releasing energy.
- what is the hydrogen economy?methods of storing hydrogen are used to enable communities to have a constant access to renewably sourced energy in times of peak and off-peak demand to reduce the issue of intermittency.
- improved uranium extraction
- polymer adsorption in seawater
- phosphate mining
- coal ash
- how is molten salt used in nuclear power?used as a reactor coolant to increase efficiency of electricity generation as it can operate at much higher temperatures without needing high pressure to prevent the coolant boiling.
- plutonium reactors (breeder reactor)
- non fissile uranium-238 converts into fissile plutonium-239 by neutron bombardment
- higher energy density so more energy harnessed
- uranium-238 is more abundant than uranium-235
- thorium reactors
- non-fissile thorium-232 can be converted to fissile uranium-233
- uranium-233 fuel rods release energy and neutrons to maintain the chain reaction
- evaluation of thorium reactors
- advantages- thorium is 3x more abundant that uranium, harder to make weapons, less radioactive waste, no fuel-enrichment needed
- disadvantages- slow breeding rate for uranium-233, releases alpha radiation, development is costly
- directional drilling
- wells drilled that aren't vertical
- many wells drilled from a single platform
- can drill underneath locations that rigs can't
- drilling can follow weaker rock strata to be quicker and can target multiple small reservoirs to increase recovery rates
- hydraulic fracturing
- large volumes of crude oil and gas is trapped in pore spaces in low permeability shale rocks
- uses high pressure to open fissures in surrounding shale so oil and gas can flow towards recovery well
- water, sand and solvents can be pumped into fissure to increase recovery rate
- concerns over hydraulic fracturing
- natural gas escaping into aquifers
- chemicals injected underground may cause pollution in aquifers or surface
- toxic metals in rock become mobile
- large volumes of water needed
- earthquakes from release of natural tension in crust
- how are tar sands extracted?
- large excavators quarry the sands which are then treated with hot water to produce an emulsion of oil droplets that float to the surface to be separated
- in-situ steam assisted extraction- steam injection produces a liquid oil that can be pumped to the surface. Oil shales are mined then oil is extracted by heating the shale to drain off fluid hydrocarbons
- primary oil recovery
- natural pressure of water below the oil or gas forces the oil up the production well for extraction.
- secondary oil recovery
- pumping water or natural gas down an injection to maintain flow and pressure of the oil.
- some ccs schemes pump recovered carbon dioxide underground to increase oil recovery rates
- tertiary oil drilling ( Enhanced Oil Recovery)
- steam can be pumped down to heat the oil or oil is heated via underground combustion in order to reduce viscosity
- detergents or solvents can be added to reduce the tension and increase flow rates
- bacteria can partially digest oil and produce lighter oil that flows more easily.
- methane hydrates
- solid ice-like crystalline found at low temperatures or under high pressure
- extraction of methane hydrate oceanic sediments
- -1-water heating- melt hydrate crystals, releasing methane
- -2-depressurisation- drilling sediment to reduce pressure to methane can dissociate
- -3-carbon dioxide injection- displaces methane that can then be collected and used in CCS