Energy Resources (AS) (Complete) Flashcards
Why and how have energy resources developed?
-Using human labour to do every task is slow, hard work
-Using animals or harnessing power of water/wind released time to develop new activities; make life easier
-Changes in energy resources continued w/ development of new technologies that harnessed new resources, increased efficiency of energy use/allowed energy to be converted—> more useful forms
What enabled the development of useful items and tools like cutting blades?
Smelting of metals using wood & charcoal enabled development of a range of useful items, eg cutting blades, nails, wheel rims, ploughs, & other tools
What energy developments did the Industrial Revolution bring from the 1700s?
-Developed use of coal & coke to produce steel—> was used to manufacture sophisticated machines, eg steam engines. These were used in many ways, like to pump water out of mines, transport goods, plough, drive timber saws & grain-threshing machines, and textile mills
-A major development= ability to generate power where it was needed by transporting coal in contrast to wind & water power that had to be used where they could be harnessed
What increased the amount of energy that can be used in the 1800s?
Crude oil, natural gas + other fuels
What has access to large amounts of fossil fuel energy enabled?
The production of a wide range of things including unnecessary products, non-essential travel and has permitted waste of energy.
Why have secondary fuels, like electricity, become increasingly important?
-Are often more useful than primary fuels from which they were produced -Many tools + convenient equipment like telecommunications systems, motors, lighting & electromagnets in appliances like audio speakers require electricity, could not be run directly from primary fuels harnessed directly from environment
What is the impact of converting energy from primary to secondary fuels not being 100% efficient?
Reduces the amount of energy that is available to be used
How have ancient civilisations and industrial societies contrastingly developed?
-Ancient civilizations developed when + where soil & climate made possible production of sufficient food to support population
-Industrial societies developed in places where fossil fuels occurred naturally/where they could be transported easily
What can the increasing use of renewable resources create?
New industrial centres locally where energy is harnessed/more disparately as energy storage & transfer become more effective
How have new uses of energy allowed the development of society?
-Tasks completed more easily
-New activities allowed
Why has the per capita energy consumption increased?
As population has grown, world’s consumption of energy has ↑in total as has per-capita consumption
What are examples of direct and indirect consumptions of energy?
-Direct uses include energy used by people individually, eg heating & lighting ther homes, cooking, personal transport, use of electrical appliances etc
-Indirect uses include; energy used by commercial organisations, schools, government + industry to provide goods & services, support economic activity, eg transport of goods, manufacturing processes, water treatment, & energy used in agricutture
Factors affecting per capita energy consumption in different countries; Affluence?
-Higher income= people buy, consume & use more energy in activities like travelling, using less efficient vehicles, heating larger home & having more energy-using appliances
-More energy is used during manufacture of additional products bought
-Affluent countries use significantly more energy to construct housing in production of bricks, glass, tiles & fittings like carpets, furnishings & appliances
-Not all countries have access to readily available sources of energy; shortages limit transportation, ability to access water, power equipment & preserve foods
-Supply + demand for energy resources set prices on world market
-Global market prices= usually low enough for more affluent communities to afford to purchase energy tor essential uses like purifying water, running hospitals & transporting food. May be able to afford energy for non-essential uses that make life more enjoyable
-Poorer communities may be unable to pay for energy needed for essential uses; can slow development of these societies, reduce quality of life
Factors affecting per capita energy consumption in different countries; Relative cost of energy?
-In countries w/ large, easily accessible local sources, energy is cheap
eg petrol= much cheaper in US than UK—> more petrol can be used for same cost. Has encouraged use of larger, less fuel-efficient cars. Fuel efficiency; likely to be lower priority if energy= relatively cheap
-Some developed countries have a low per capita energy use within own country
-However, they import goods that used a lot of energy in their manufacture in other countries, eg steel, copper, aluminium
-Per capita energy consumption in countries like UK has gone down in recent years—> partly due to decline of industries like steel & aluminium smelting; now produced for us in other countries, eg China
What are the 4 different types of industry and their levels of energy use?
-Primary industry; agriculture, mining, raw material extraction. General level of energy use= high
-Secondary industry; heavy manufacturing industry,eg metal smelting, chemical industry. General level of energy use= high
-Tertiary industry; services like transport, finance, retail I recreation education. General level of energy use= low
-Quaternary industry; information & IT. General level of energy use= very low
How have social and environmental awareness driven changes in energy use?
-Regions & locations which historically had difficulty satisfying demand for energy often have tradition of managing energy use carefully. Scandinavia → energy shortages in past, especially remote communities; driven strong energy conservation culture
-In UK → access to large deposits of coal drove Industrial Revolution & society’s development, but energy also used wastefully. As coal mining ↓, access to natural gas & oil from N sea extended extravagant use of energy
How does the climate affect energy usage?
-Buildings in locations w/ cold winters require heating & those in v hot areas require air conditioning
-High winds ↑ heat losses while sunny weather ↑ passive solar heat gains
What are examples of how energy is used in agriculture and fisheries?
-Fuel for machinery, eg tractors & combine harvesters, water pumping, fish farm aeration
-Manufacture of chemicals like fertilisers
-Food processing, eg sugar refining, grain drying & milling
-Transport of materials & harvested food
-Storage, especially refrigerated foods
-Fuel for fishing boats, water pumping & aeration in aquaculture
What are examples of how energy is used in other industries?
-Machinery operation; excavators, rock crushing, pumps, presses, conveyor belts, mixers, cutters, lathes
-Heat to melt materials for moulding & casting of metals & plastics
-Energy for chemical reactions; smelting metals, thermal decomposition of limestone in cement manufacture
-Heat for baking, eg pottery, bricks
-Heat for distillation, eg fractional distillation of crude oil
-Water treatment for public supply
-Sewage treatment
What are examples of how energy is used domestically?
-Space heating
-Lighting
-Running appliances, eg refrigerators, washing machines, dishwashers, cookers
What are examples of how energy is used for transport?
-Transport of goods; ships/ trains/trucks/conveyor belts/pipelines
-Transport of people; cars, buses, trains, planes
What are examples of how industrial development has caused changes in energy use?
-As countries like Brazil, China & India have industrialised, their use of energy has ↑ rapidly, especially in mining & manufacturing industries
-As heavy industry + manufacturing activity have ↓ in UK, so has industrial energy use
What are examples of how income levels have caused changes in energy use?
-↑ in income = consumers afford to pay more for energy, eg heating, lighting & transport
-Affluence enables higher consumption of goods, ↑ energy required for manufacture & transport
-Household appliances like washing machines, TVs & fridges require energy to run. As segments of societies in developing countries like India
& China became more affluent, domestic consumption ↑
What are examples of how population growth has caused changes in energy use?
-Total energy use ↑ w/ population growth even if per-capita use remains the same
-If population of developing country = graving rapidly, may struggle to ↑ energy supplies fast enough to match demand
What are examples of how changes in environmental awareness have caused changes in energy uses?
-May lead to choices that lead to lower energy consumption, like;
- Better building energy conservation
- Choices of vehicle type & usage
- Choices of consumer goods
- Food choices
- lLevel of recycling
Features of energy resources; what is the different between renewable and non-renewable energy resources?
-Renewable; naturally re-form relatively quickly so using them doesn’t necessarily ↓ future availability, eg solar, wind, wave, tidal, geothermal & biofuel energy
-Non- renewable; not being formed/ re-form so slowly that current use ↓ amount available for future use, eg fossil fuels, uranium
Features of energy resources; what are depletable energy resources?
Where use can ↓ future availability. Include all non-renewable resources & those renewable resources where unsustainable exploitation may ↓ availability, eg wood; forests are felled faster than they re-grow
Features of energy resources; what is the abundance of an energy resource and what factors impact its availability?
Measures # of resource existing; not the same as # available for use as there may be other factors restricting availability, eg;
- fossil fuels deep underground, cannot be extracted
- winds high above ground when aerogeneraters can’t be located
- wave power far from coast where water = too deep to anchor equipment
- low intensity sunlight that can’t produce high temps
New technologies &↑ energy prices may make resources that can’t currently be used viable in future
Features of energy resources; how do locational constraints impact energy resources?
-Energy resources aren’t evenly distributed; each has its own locational factors
-Energy sources that can only be accessed via extraction like fossil fuels & uranium ore must be located in more favourable deposits
-Energy sources that harness natural processes may depend on regional/ local features like climate & topography
What are the main locational factors & required conditions for fossil fuels?
-Can only be extracted where economically exploitable deposits exist
-Power stations require access to; fuel supplies, condenser cooling water (large river/ lake/sea), suitable construction site
What are the main locational factors and required conditions for nuclear power?
-High energy density fuel = easily transported
-Power stations require access to; condenser cooling water (river/ lake/ sea), suitable construction site
What are the main locational factors & required conditions for solar power?
-High light intensity
-Low cloud cover
What are the main locational factors & required conditions for wind power?
-Areas w/ strong, reliable winds like; shallow seas, open plains, upland areas
-Areas w/ low land-use conflicts (especially for large wind farms); not areas of high ecological sensitivity, not close to urban areas, not in areas of high scenic importance
What are the main locational factors & required conditions for wave power?
Coastal areas w/; strong, reliable winds over water, reliable prevailing wind direction, long fetch (long stretch of water over which wind blows)
What are the main locational factors & required conditions of Hydro Electric Power (HEP)?
Areas w/;
-High, reliable rainfall
-Site for small dam w/ large reservoir basin
-Large catchment area
-Impermeable bedrock
-Stable geology
What are the main locational factors & required conditions for biofuels?
-Nearby forest areas
-Farmland for biofuel crops
-Farmland for crop/ livestock waste
-Nearby urban areas for food waste/sewage
What are the main locational factors & required conditions for geothermal power?
Areas w/;
-Hot rocks near ground surface
-Recent volcanic activity
What are the main locational factors & required conditions for tidal power?
Areas where;
- Tidal range= large
-Coastal features that focus tidal flow to ↑ flow velocity/tidal power
Features of energy resources; what is intermittency in energy resources?
If an energy resource isn’t available at times when it’s needed then it’s difficult to rely on it, eg wind, solar, tidal power
Features of energy resources; what is predictability within energy resources?
-It’s important to know how much energy will be available & whether it’ll meet demand for energy
-Some resources= intermittent but time they’ll be available can be predicted accurately, eg tidal power, ; means plans can be made to use alternative resources when they’re unavailable
-Other resources are both intermittent & unpredictable, eg solar power & wind power
Features of energy resources; what is energy density and how is it significant?
-Measure of # of energy in given mass of energy resource, eg. oil, coal, uranium, wood.
-For some resources, eg many renewable resources, it’s the # of energy harnessed by given mass of equipment
-Generally, high energy density resources are most useful as smaller quantities are needed so storage + transport are easier and it is easier to reach ↑ temps
-A low energy density resource is often less useful if used directly, but it can still be useful. Eg; Solar & wind power have low energy density but electricity produced can be used to paver technologies w/ a high energy requirement
What is the order of energy density from highest to lowest of selected energy resources?
Nuclear fusion/fission, hydrogen, fossil fuels, wood, wind power and solar power
Features of energy resources; how is resource availability impactful?
-Potential contribution of a resource to energy supplies= clearly affected by # of energy available
-Can be difficult to estimate how much of resource can be harnessed
-May be abundant resources which can’t be exploited w/ any existing technology/ likely to be developed, eg wind at high altitude
Features of energy resources; why is there a need to convert energy resources to increase usefulness?
-Form in which energy is harnessed → not necessarily form in which will be delivered to end-user
-eg chemical energy of fossil fuels is converted to heat, potential, kinetic then electrical energy before it can be used to power electrical appliances
-Some resources that currently seem to be of little use may become important if appropriate technologies are developed to convert them to more useful energy forms
Features of energy resources; how is applicability to specific uses significant?
-Available energy resources have shaped the way that societies have developed, so it can be difficult for society to change to using energy resources w/ different characteristics
-Renewable energy resources → making more significant contribution to our energy supplies, have different characteristics from fossil fuels & nuclear power
-^While a number can generate electricity, none can reach temp levels that fossil fuels create/produce liquid fuels in good quantities to power all vehicles
Features of energy resources; why is ease of storage significant?
-Energy demand & supply levels vary, rarely balance
-Being able to store energy → important so it’s available when required
-Some energy resources like chemical energy in fossil fuels can be stored easily, especially due to their high energy density; where small mass/ volume stores large # of energy
-Some energy resources, eg solar, wind, wave can’t be stored unless they’re converted into other forms. Can be converted thermal/chemical/ GPE which can be stored
Features of energy resources; why is ease of transportation significant and what is it impacted by?
-Energy resources are rarely found in areas where demand is highest, so must be transported
-Affected by properties like form of energy & energy density
How is coal mainly transported and what happens alternatively if too difficult?
-Ship, train
-Often used in large scale industries like electricity generation/ smelting iron. It’s often easier to transport electricity & steel than coal, so power stations + iron & steel works → often located near coal fields/deep water parts where coal is imported
How is crude oil mainly transported and how is it utilised?
-Pipeline, ship, rail tanker
-Transported in large quantities from oil fields to oil refineries where refined products are made, like aviation fuel, petrol, diesel, fuel oil
-Bulk transport methods used
How are refined oil products transported and where are they distributed?
-Pipeline, ship tanker, rail tanker, truck
-Products of oil refining → usually distributed to relatively local consumers in ↓ quantities than crude oil
What are the ways in which natural gas is transported and why?
-Pipeline, liquefied natural gas (LNG) ship tanker, rail tanker
-Can be piped easily from gas fields—> areas where demand is high, eg large industries/urban areas w/ large # of consumers
-Natural gas, in its gaseous form, has a ↓ energy density so transport by ship where pipelines don’t exist require liquefaction to ↑ energy density
How are fissile fuels, like uranium, transported and why?
-Solid fuel rods/pellets by rail or truck
-Relatively small quantities of fissile fuels need to be transported due to high energy density
-Are transported in solid form in containers designed to withstand fire and impact; may have outer casting for more protection
How are biofuels transported and why?
-Road, rail, ship
-Each has its own transport features
-Liquid biofuels, og alcohol, have quite ↑ energy density so transport over long distances = practical
-Solid biofuels, eg straw → very bulky law mass per unit volume so long distance transport may not re practical as transport energy inputs may be high
What is done to primary fuels; solar, wind, hydroelectric tidal and geothermal because they can’t be transported?
-Conversion to other energy forms that can be transported
-Can be used to generate electricity that can be transported
How is electricity transported and why?
-High voltage AC/DC electricity grid
-Overhead power cables = cheaper to install & maintain than underground cables
Features of energy resources; why are environmental impacts significant?
-Exploitation of all energy resources damages environment in variety of ways; some obvious, like pollution during extraction & use of fossil fuels but link w/ impacts like global climate change may be less obvious
-All energy resances cause damage via manufacture of equipment needed to exploit them
Features of energy resources; why is technological development significant?
-All technologies have period of development before they can be used practically, followed by period of further development when technology is refined to improve it so becomes more efficient, effective, cheaper
-Can be difficult for new technology to be financially viable during early development if has to compete w/ existing technologies; whose development costs have already been paid for + have economic benefits of mass production
Features of energy resources; how do political influences aid the energy industry?
Governments may decide to provide assistance to particular sections of the energy industry, to;
-Support development costs of new technology, eg grants for developing new renewable energy technologies
-Increase national energy security, eg grants/ tax reduction for oil exploration
-Reduce environmental impacts, eg EU grants for low carbon technologies
Features of energy resources; how do energy resources cause economic implications?
-It’s not easy to calculate full cost of using energy; price paid by energy user doesn’t always cover total costs including environmental damage & cost of mitigating these
-Burning fossil fuels → pollution, including acid rain; produces financial impacts elsewhere, eg building damage. Cost aren’t paid by energy users
-It’s difficult to assess cost of some impacts, as issues aren’t fully understood
Features of energy resources; how are different energy projects paid for?
-Cost of energy project can be divided into running costs during operational life & set-up costs to make & install equipment
-Running costs → paid w/ income from energy produced
-Set-up costs → often paid for w/ loans with interest
-If renewable energy project is compared w/ non-renewable of same actual post renewable energy project may still be at financial disadvantage
-Cost of renewable energy projects= mostly initial cost of equipment, w/ very low running costs, so most of expenditure= from loan. Cost of non-renewable energy project—> mainly running costs, especially fuel, which won’t require loan w/ interest payments
-So, renewable project has to cover higher interest payments, making total cost higher than the non-renewable energy project
How has resource depletion impacted the sustainability of current energy use?
-Fossil fuels provide most global energy supplies but are non-renewable; availability must decline in future as reserves deplete
-New technologies & ↑ market prices may convert more of resource into reserves so they can be exploited, but principle of resource depletion = still controlling factor that must restrict supplies eventually
-There are still large reserves of fossil fuels that haven’t been exploited, but rate of discovery of new deposits has ↓ dramatically since 1980s
Why will choices made about energy resources affect economic sustainability?
-Depleted non-renewable resources will become more expensive. As energy is needed for so many aspects of life; could ↓ future affluence
-Commitments made now for long-term use of expensive technologies like nuclear power could ↓ future affluence, but may help secure energy supplies
-Failure to invest in development of future energy supplies may → shortages for future gens. When a new technology is 1st introduced it’s usually expensive as development costs are still being paid for, no economies of scale in manufacturing that would eventually ↓ costs. It’s hard for these now technologies to compete w/ well established, cheap ones like fossil fuels. Waiting until depleted fossil fuels → expensive & new technologies → competitive would make energy gap as it would take time to develop technology & necessary infrastructure
How can environmental impacts of energy resources reduce sustainability?
-All energy resource exploitation has an environment impact but there’s differences in scale, type & timing of impacts
-Many impacts = temporary/local/small, so they don’t affect global sustainability but combination of these may → significant
-New technologies may be developed that’ll ↓ environmental impacts like ability to capture CO² emissions but it’d be risky to commit to further large-scale fossil fuel use before technique has been proven
What are the impacts before use of different energy resources?
-Fuel extraction; coal mining, oil extraction
-Fuel processing; coal, crude oil
-Equipment manufacture; causes environmental damage in material extraction & processing
-Site development / operation; preparing sites for equipment & associated infrastructure → habitat damage
-Transport; (of fuels) uses fossil fuels
-Embodied energy in equipment; manufacture for every resource uses energy, although # varies greatly between different resources
-Acid mine drainage & subsidence; coal mining
-Methane releases; extraction of all fossil fuels
What are the pollution damages consequential of energy resource use?
-Atmospheric pollution; fossil fuels
-Oil pollution; oil, tar sands, oil shales
-Radioactive waste; nuclear power
-Noise pollution; wind power
-Thermal pollution; steam turbine power stations
What are the habitat damages consequential of energy resource use?
-During extraction of energy resource; fossil fuels uranium, biofuel crops
-Power station & equipment location; all energy resources during equipment installation
-Ecological impacts of tidal power schemes; changes in flow velocity, tidal range, sedimentation, turbidity
-Ecological impacts of HEP schemes; downstream changes in flow velocity, turbidity, dissolved oxygen, barrier to movements of wildlife
-Pipelines & cables; oil, gas, electricity
-Depletion of reserves; non-renewable energy resources
What are the reasons for the ways that energy is supplied changing in the future?
-Some existing resources like fossil fuels & wood are becoming depleted
-Concerns on environmental damage are affecting political policies & public opinion
-Current supplies can’t meet growth in demand due to increasing affluence & population growth
-New technologies becoming available to harness, store, transport, convert energy into forms required
Future energy supplies 1- Fossil fuels; how were all fossil fuels produced?
The partial decomposition of dead organic matter under anaerobic conditions beneath layers of sediments that were deposited on Earth’s surface/seabed. Took place over long periods of time, most coal was formed 300- 360m years ago
Future energy supplies 1- Fossil fuels; what are the features that make fossil fuels ideal to use?
- They’re easy to store
-They have high energy density so can power high energy intensity activities like powering steam engines. Also means they’re relatively efficient to transport; given volume/mass contains a lot of energy
-Are often found in very abundant local deposits
Future energy supplies 1- Fossil fuels; why is the chemical energy of fossil fuels useful?
It’s easy to store and easy to convert into heat energy that’s usually required
Future energy supplies 1- Fossil fuels; why is the high energy density of fossil fuels so useful?
-High temperatures made by burning coal enables smelting of metal ores
-Burning fossil fuels reach temperatures high enough to produce high pressure steam which can spin turbines & generators in power stations to generate electricity
-Allows small mass of fuel to do a lot of work, so 5L of petrol can carry 1 tonne of car for 80km
-75t of aviation fuel can carry a 400t Boeing 747, including 400 passengers for 5,600km. If fuel had ↓ energy density then weight of fuel carried may make flight impossible
Future energy supplies 1- Fossil fuels; why are fossil fuels being finite resources significant?
-Non-renewable energy resources = finite resources → exploitation means they’ll became depleted
-Is important where industrial communities have grown up on local fuel supplies. Once local supplies are exhausted industry may only survive if supplies from elsewhere can be transported easily & economically
Future energy supplies 1- Fossil fuels; why is the amount of available resource of some fossil fuels an issue?
-Significant amounts of oil & coal = unexploitable as deposits are too deep/ found in small amounts/ located in hard to reach areas
-A lot of natural gas → trapped in fine-grained impermeable shale deposits
-Oil shale= fine-grained sedimentary rock containing solid hydrocarbons that can yield substantial # of oil & combustible gas upon destructive distillation. Most of the organic matter → insoluble in ordinary organic solvents, cannot flow to surface like crude oil. So, it must be decomposed by heating to release oil by melting it so it can flow to surface. Total contained in shale deposits> total reserves of crude oil
Future energy supplies 1- Fossil fuels; why may the large-scale use of recoverable fossil fuels not be possible despite their large quantity?
-It’s not economically viable
-May cause unacceptable pollution
-May involve habitat damage in ecologically sensitive areas
-Extraction process may cause local earth tremors
Future energy supplies 1- Fossil fuels; why is the level of technological development significant for fossil fuels?
-Industrial societies have developed using fossil fuels so technologies to exploit them = well-developed
-Many applications that use energy have been developed so they use fossil fuels, like cars, trucks, aircraft
-To change to other sauces of energy will involve many changes in the infrastructure of society
Future energy supplies 1- Fossil fuels; why can fossil fuels cause political and international trade problems?
-↑ demand drives energy-hungry countries to satisfy own energy needs; can influence political decisions to protect future supplies at expense of ↓ both local & global environmental impacts
-Crude oil → basis of most of world’s energy but deposits are unevenly distributed across globe; majorly in Middle East, so is the focus of both trade & political interest
Future energy supplies 1- Fossil fuels; how have fossil fuels created economic issues?
-Economic activity + international trade can drive countries to make decisions based on cheapest options; may not be best long-term
-When cheap natural gas became available in UK → contributed to closure of deep coal mines even though many coal deposits remained, could still be extracted. Even though North Sea gas reserves will be exhausted in next 30/ 40 years, it want be possible to reopen coalmines as they have flooded & are unsafe
-Fossil fuels generate economic costs like pollution damage; not paid for by energy industry but by others like agriculture, forestry, health service
Future energy supplies 1- Fossil fuels; what are the extraction methods for coal and how are they done?
-Deep mining & open cast mining
-Deep mining; labour intensive so relatively expensive to produce large # of coal
-Open cast mining; mechanised so usually more economically viable but as it’s necessary to clear all rock above coal it’s only viable in locations where coal is close to surface
-Deep deposits, very thin seams can’t be accessed by either method
Future energy supplies 1- Fossil fuels; what are the environmental impacts caused by the extraction methods of coal?
-Environmental damage caused by deep mining → predominantly at surface via habitat loss, transport infrastructure & potentially surface subsidence
-Open-cast mining causes greater habitat damage
Future energy supplies 1- Fossil fuels; what are the extraction methods for oil and gas?
-Petroleum (crude oil) in liquid form flows through permeable rock & collects in porous rock in pores between particles
-When a pipe is drilled ↓ to these reservoirs, oil will be forced to surface by natural pressure of gas above oil/water beneath oil
Future energy supplies 1- Fossil fuels; what are the environmental impacts from oil & gas extraction methods?
-Oil spills from oil rigs → pollution
-Oil-based drilling mud used to lubricate drill pipes → pollution in groundwater, rivers & sea
-Surplus gas on oil rigs may be burnt / ‘flared’ to ↓ risk of explosions, causes atmospheric pollution via pollutants like sulfur dioxide, carbon dioxide & smoke
-Natural gas= extracted by similar means to oil extraction, forced to surface by own natural pressure
Future energy supplies 1- Fossil fuels; what are the environmental impacts of coal mining?
Habitat loss, noise, dust, turbid drainage water, spoil heaps, acid mine drainage, methane releases, derelict sites
Future energy supplies 1- Fossil fuels; what are the environmental impacts of oil extraction and transport?
Oil pollution marine, seismic surveys, habitat damage due to pipeline construction
Future energy supplies 1- Fossil fuels; what are the environmental impacts of the combustion of fossil fuels?
-Atmospheric pollution: Carbon dioxide, sulfur dioxide, oxides of nitrogen, carbon monoxide, smoke
-Ash disposal
Future energy supplies 1- Fossil fuels; what are the main uses of crude oil?
- Liquid vehicle fuels; petrol, diesel, aircraft fuel, ship fuel oil
- gas fuels for heating; propane, butane
- petrochemicals; plastics, feritilisers, pharmaceuticals
Future energy supplies 1- Fossil fuels; what are the main uses of natural gas?
-Domestic & industrial heating
-Electricity generation
-Chemicals: nitrate fertilisers
Future energy supplies 1- Fossil fuels; what are the main uses of coal?
-Electricity generation
-Iron & steel industry
New fossil fuel technologies; how does coal gasification benefit coal exploitation?
Coal too deep to be mined can be burnt underground under controlled conditions to produce mixture of fuel gases like hydrogen, carbon monoxide & methane
New fossil fuel technologies; how does coal liquefaction benefit coal exploitation?
-Involves conversion of coal to liquid hydrocarbons which have applications that solid coal can’t perform like liquid vehicle fuels
-Coal may be converted to liquids directly w/ solvents or indirectly w/ gasification then chemical changes to convert gaseous hydrocarbons → liquid hydrocarbons
New fossil fuel technologies; what is primary oil recovery and its process?
-Well-established method using natural pressure of water below oil/ gas present above oil/ dissolved in it
-Pressure forces oil ↑ production well to surface
-Approx 20% of oil is usually extracted
-Pump-jack fitted at ground level on production well may be used to ↑ flow rate
New fossil fuel technologies; what is secondary oil recovery and its process?
-Involves pumping water/natural gas down injection well to maintain pressure & flow of oil
-↑ total recovery rate to approx 40%
-Some CCS schemes pump recovered CO2 underground to ↑ oil recovery
New fossil fuel technologies; what is tertiary oil recovery and its process?
-Includes techniques ↓ viscosity of oil, also called Enhanced Oil Recovery (EOR)
-Steam (generated by burning fuel/solar heating schemes via parabolic concentrators) may be pumped ↓ to heat oil
-Oil viscosity may also be ↓ by controlled underground combustion → heats it up
-Detergents/solvents ↓ surface tension of oil, make it flow more easily
-Bacteria used to partially digest heavy oil & produce lighter oils flowing more easing. They also make CO2 → helps maintain pressure & flow of oil
-Typically ↑ total recovery rate to approx 60%
New fossil fuel technologies; what is directional drilling and what are its advantages?
-Allows wells to be drilled that aren’t vertical, many advantages;
-Many wells can be drilled from single platform
-Possible to drill underneath locations where drilling rigs couldn’t be placed, eg urban areas
-Drilling can follow weaker/ softer rock strata to make drilling quicker & can target multiple small reservoirs up to 10km from well head → can significantly ↑ total recovery rates
New fossil fuel technologies (oil); what are subsea production wells and what do they allow?
-Located on seabed, have no platform at sea surface
-Allow operations in water up to 2000m deep but new developments will allow greater depths
New fossil fuel technologies (oil); What are Remotely Operated Vehicles (ROVs) and Autonomous Unmanned Vehicles (AUVs) used for?
Can be used to carry out seabed surveys, inspect underwater production equipment & pipelines
New fossil fuel technologies (oil and natural gas); what is the process of fracking?
-Large volumes of crude oil & natural gas → trapped in pore spaces of shale rocks w/ Iow permeability (called tight oil & gas)
-Hydraulic fracturing uses ↑ pressure to open fissures in surrounding shale rock along which oil/gas can flow towards recovery well
-Water, sand grains & solvents may be pumped into fissures to ↑ recovery rate
New fossil fuel technologies (oil and natural gas); what are the concerns over fracking?
Experience in USA shows tracking can cause environmental problems but good management may minimize these. Examples;
-Natural gas may enter aquifer water
-chemicals injected underground may enter aquifers/reach surface, cause pollution
-Toxic metals naturally present in rocks may become mobile
-Large volumes of water are needed
-Earthquakes; natural tensions in crust due to continental drift & isostatic movements post erosion may cause earthquakes. Fracking may release some of these tensions, but shoudn’t cause earthquakes that wouldn’t occur naturally
New fossil fuel technologies (oil and natural gas); how can potential problems due to fracking be reduced?
Methods like collection & treatment of waste water, reuse of waste water & restrictions on location of fracking sites in sensitive areas
New fossil fuel technologies (oil); what are the 2 methods of extracting tar sands?
-Sands are quarried w/ large excavators, then treated w/ hot water. Produces emulsion of oil droplets that floats, can be separated. 1 barrel (150L) of oil is produced from 2T of tar sands. About 75% of oil is recovered, waste sand is backfilled into mine
-In-situ production uses steam injection/solvent/controlled combustion in deep deposits to make liquid oil → can be pumped to surface. High energy inputs make extraction expensive
New fossil fuel technologies (gas); what does Enhanced Gas Recovery (EGR) involve?
↑ gas recovery rates w/ techniques like injection of CO2/nitrogen around edge of gas field to maintain pressure & gas flow
New fossil fuel technologies (gas); what is methane hydrate/clathrate and is it exploited?
-Solid ice-like crystalline solid found in locations at low temps like polar regions/under high pressure, eg oceanic sediments around continents
-Not exploited commercially now but could yield more methane than conventional natural gas sources
New fossil fuel technologies (gas); what are the proposed methods for exploiting methane hydrate oceanic sediments?
-Water heating; hot water is pumped into sediments, which melts hydrate crystals, releasing methane gas
-Depressurisation; drilling into sediments causes pressure to ↓. Methane gradually dissociates from hydrate crystal
-CO2 injection; at ↑ pressures, CO2 can form bonds w/ ice crystals but bonds more strongly than methane. Injecting CO2 could displace methane, can then be collected. Could also be used as part of CCS scheme
New fossil fuel technologies; how can CCS benefit fossil fuel use?
-Involves range of developmental technologies which would store coz produced by fossil fuel use &↓ CO2 releases
-In theory could make extended use of fossil fuels possible
-Its unlikely that CCS could be applied to small, dispersed uses like vehicles but it may be possible to use it to capture CO2 at large power stations then use electricity to make non-carbon fuels like hydrogen
Future energy supplies 2: nuclear power; what does nuclear power involve + equation?
Conversion of small amounts of matter into energy as atomic nuclei split/ join: e=mc²
E = energy released
M= mass of matter lost
C= speed of light
Future energy supplies 2: nuclear power; what does nuclear fission and fusion involve and when is energy released?
-Huge # of energy is released during destruction of small # of matter
-Large # of energy are released when small # of matter from nuclei of atoms are destroyed
-Nuclear fission; splitting of nuclei of large atoms like those of isotopes uranium-235 & plutonium-230
-Nuclear fusion; joining of nuclei of small atoms like those of isotopes hydrogen-2 & hydrogen-3
Future energy supplies 2: nuclear power; why is nuclear power usually used for ‘base-load’ electricity supplies, needed all the time?
The power output of nuclear reactors normally changes quite slowly
Future energy supplies 2: nuclear power; what are the factors that have restricted the growth of nuclear power?
-Technology is very complex → difficult to use in less technologically advanced societies which can’t support industrial infrastructure needed
-Complex technology needed= very expensive
-Strong public opposition to nuclear power in some countries due to concerns over safety, esp following reactor accidents, eg Chernobyl, Ukraine 1986 & Fukushima, Japan 2011 + impacts such events have on short & long term health of people + environment
-Concerns about possible links between nuclear materials for civil uses & military/terrorist use
-Uncertainty over permanent disposal of radioactive waste
-uncertainly over total $ of nuclear power since no commercial reactor has been fully decommissioned
Main features of nuclear fission; why is its high energy density beneficial?
-Nuclear fuel used in nuclear power stations have very ↑ energy density so small # of fuel releases large # of energy
-1 kg of uranium fuel can release as much energy as 13T of coal
-So, nuclear power stations do not need continual supplies of large # of fuel, so can be located where transport infrastructure isn’t as good as that required for coal-fired power station
-Nuclear reactors provide power for some surface ships, many submarines; rarely need to be refuelled, don’t need air supply to operate
Main features of nuclear fission; why is the embodied energy required for nuclear fission significant?
-Despite its high energy density, processes required to make fuel & complexity of nuclear power stations require lots of energy
-Coal requires very little processing but uranium must be purified, concentrated & chemically processed to produce fuel
Main features of nuclear fission; why are fissile materials being finite resources significant?
-Fissile materials, eg uranium & thorium= non-renewable resources, so # existing ↓ as they’re used, but depletion will only become an issue if supplies become restricted → more dependent on technological ability to extract them than actual # existing
-A huge amount of uranium exists but most is found in v↓ purity deposits that can’t be exploited economically at current prices
-Energy cost of extracting uranium w/ conventional methods on lower grade deposits may be > would be released when uranium underwent fission
-New technologies in future may extract fissile fuel w/ less energy
Main features of nuclear fission; how has technological development allowed nuclear reactors to be more efficient?
Nuclear reactors powered by uranium have been used for commercial electricity generation since 1950s, reactors currently being built are described as 3rd generation reactors. Lessons learned from previous reactors have allowed improvements in design;
-Longer reacted life (60+ instead of 40+)
-More reliable operation
-Lower fuel consumption
^give advantage over thorium reactors
Main features of nuclear fission; what are the environmental impacts from nuclear energy production?
-Mining & processing of uranium/thorium ore to make nuclear fuel; habitat loss, noise, dust, turbid drainage water, hazardous waste
-High embodied energy of materials used; contribution to global climate change
-Reactor accidents & radioactive waste; health risks of ionising radiation
Main features of nuclear fission; what are the possible political and international difficulties associated with nuclear fission?
Possible link between civil nuclear electricity & preparation of weapons-grade fuel has led some countries to try to restrict availability of technology to other countries considered untrustworthy
Main features of nuclear fission; why has nuclear power caused economic issues?
-New nuclear power stations → large engineering projects, very expensive
-Inclusion of new design features & unforeseen problems often cause total $ to far exceed OG estimates
-Very few old reactors have been fully decommissioned. Costs have proved to be much greater than anticipated & funds have often not been put aside from income during years of operation to pay for decommissioning
-If cost over-run is paid by state then nuclear power → receiving subsidy making it appear more economically competitive than actually is
