Energy Resources Flashcards
What is per captia energy consumption?
The amount of energy consumed per person
What is the difference between direct and indirect energy consumption?
Direct is the energy used individually in things like lighting or transport while indirect is commercial or public uses of energy
What is affluence and what effects does it have on energy?
Affluence is a measure of the wealth of the people in an area. Increased affluence leads to more buying, consuming, powering, heating and therefore more energy use. Energy prices are based on global affluence and so poorer countries may have less access.
What are the types of industry and how much energy do they use per output?
Primary (such as agriculture or mining) uses high energy
Secondary (heavy manufacturing) uses high energy while Secondary (light manufacturing) uses medium levels
Tertiary (services like transport) use low levels
Quaternary (IT and information) uses very low levels
How do resources dictate energy use?
Countries with historically lower energy resources will typically produce energy usage methods that require less and are more sustainable, even with access to more energy in the modern period
What things can change energy use?
- Industrialisation
- Primary Industry
- Income and Affluence
- Population growth
- Changes in environmental awareness
Name some features of Energy Resources
- Renewability
- Depletability
- Abundance
- Location Constraints
- Intermittency
- Predictability
- Energy Density
- Availability
- Applicability
- Ease of Transport and Storage
- Environmental impacts
- Technological needs
What is the difference between renewable and depletable energy sources?
Renewables can re-form quickly and so their use is sustainable. Depletable resources are those that can have future use impacted by overuse now, including renewables like wood.
What is abundance?
The amount of a resources that exists NOT just what we can get to
What are locational factors for Fossil Fuels
- Need exploitable deposit
- Stations need cooling water
- Stations need a lot of space
What are locational factors for Nuclear
- Cooling water and space
What are locational factors for Solar
High light intensity with little cloud cover
What are locational factors for Wind
- Strong reliable wind
- low land-use conflict
What are locational factors for Wave
strong reliable current and a long fetch
What are locational factors for HEP
- reliable rainfall
- reservoir
- catchment area
- impermeable bedrock
- stable geology
What are locational factors for Biofuels
A local source of biomass
What are locational factors for Geothermal
hot rocks and recent volcanic activity
What are locational factors for Tidal
large tidal range with a focused flow
What are intermittency and predictability?
Intermittency is how frequently a energy source available while predictability is how accurately we can determine when they will be available
What is energy density? What has the highest, lowest and middling?
The amount of energy in a given mass of resource.
Nuclear is the highest, then fossil fuels and hydrogen, then wind and solar below that.
How can Solar, Wind, Hydroelectric and geothermal energy be transported?
They must be converted into other energy forms that can be transported
How can politics and economics effect energy source usage?
- Support for new tech development
- Increase energy security
- reduce climate impacts
- financial grants
- market price of electricity
- less strict planning for favourable sites
What are fossil Fuels?
Fuels produced by partial decomposition of dead organic matter in anaerobic conditions over extremely long periods of time
What are the positive features of Fossil Fuels?
- High energy density, so a small amount goes a long way
- Very large quantity of available resource
- Need for better extraction machinery increases drive for innovation
What are the negative features of Fossil Fuels?
- Finite resource as fuels take millions of years to be produced
- A lot of stores are non-viable
- High pollution levels
- Extraction causes large habitat damage and noise pollution
- High demand can cause political and trade issues
How can Coal be extracted? What issues do these methods have?
Deep Mining or Open Cast Mining both of which can cause environmental damage and require transport and other infrastructure.
What is crude oil called and where can it be found?
Petroleum, which can be found in porous rock reservoirs
Where can gas be found?
In underground reservoirs
How are gas and oil extracted? What negative consequences can this have?
Drilling a pipe down into the reservoir, which forces the gas or oil up under the pressure. Oil spills, sedimentation and habitat damage
What new technologies are there for coal extraction?
- Coal gasification, which involves the burning of deep deposits to produce gas fuels
- Coal Liquefaction, which turns coal into liquid hydrocarbons for use as vehicle fuels or other liquid uses.
What new technologies are there for oil extraction?
- Secondary Recovery, which involves pumping water or gas down the oil well to keep pressure consistent
- Tertiary Recovery, involving lowering the viscosity of oil using heat or bacteria to allow it to flow better
- Directional drilling, allowing wells to be dug in non-vertical directions for easier access to deposits
- Remotely Operated Vehicles can survey areas
- Fracking (Hydraulic Fracturing) uses high pressure to open fissures so oil can flow to a well
What is CCS? How does it relate to energy reources?
Carbon Capture and Storage. It could potentially allow fossil fuels to be used for extended periods without huge consequences
What is nuclear fission?
When a neutron is fired into a uranium atom, splitting it into more neutrons, fission product and energy in the form of heat
What are the positive features of Nuclear fission?
- Very high energy density
- Minimal environmental impacts during use
What are the negative features of Nuclear fission?
- High embodied energy
- Uranium is a finite resource
- Needs expensive and highly developed technology
- Requires reliable operation and training
- Health risks of radiation
- Political issues
- Economic issues
What new ways of Uranium extraction are there?
- Polymer adsorption, allowing extraction from seawater and other liquids
- Phosphate mining, allowing extraction from phosphate sources
- Coal ash, only economic if uranium prices rise
What new fission reactor designs are there?
- Molten salt, used as a coolant
- Plutonium reactors which take fission products and convert them into plutonium to be reused
- Thorium fuel rods which can be converted into uranium
What is Nuclear Fusion?
The joining of small atoms together to produce new atoms and energy
What fuel does Nuclear Fusion use?
Deuterium (hydrogen-2) and tritium (hydrogen-3)
What conditions are needed for Nuclear Fusion?
- Hydrogen as plasma
- Heavy Nuclei
- Very high temps
- Vacuum
- Magnetic field
What is Laser Fusion?
A small scale fusion technology that is easier to refuel and operate
Why can renewable energy resources often be unreliable?
Since they rely on natural processes we don’t or can’t fully understand and predict we never know how much or when energy will be available from them.
What are the economic issues of renewable energy resources?
They often require new and/or expensive technology that require a lot of research and money to produce and current infrastructure relies heavily on fossil fuels, so replacing them would not be easy
What are the problematic properties of solar power?
- Intermittent
- Unreliable and unpredictable as cloud, smoke or dust cover cannot be easily predicted
- Low energy density
- Require placement in specific areas that are prone to sunlight
- Manufacturing requires processing of metals, plastics and silicon which can have negative environmental impacts
- Large solar farms can occupy space otherwise used for farming
What are the 4 current methods of Solar Power?
- Photothermal, which absorb sunlight to produce heat to warm water for space heating or domestic use
- Passive Architecture, which maximises the absorption of sunlight for heating
- Heat-transfers, which sunlight is absorbed to heat water, which can in turn heat other water when ran through it in pipes
- Photovoltaic, which absorbs photons, dislodging the PV’s electrons which flow along a conductor to produce electricity
What new technologies exist for solar power?
- Multijunction photovoltaic which absorbs different wavelengths at different levels, ensuring more light is taken in
- Anti-reflective surface texture which increases absorption of heat
- Thermal storage, which allows the continued storage of the heat generated using molten salt
- Heliostats, which rotate panels to always face the sun
- Self-cleaning panels that use nanohydrophobic surfaces
What are the problematic properties of HEP?
- Particular site is needed
- Requires large volume of water
- Can destroy habitats for reservoir creation
- Reservoir decomposition can release methane
- Increased sedimentation in the river
- Changes in flow regime of the river
What is the difference between high head and low head HEP?
- High head has a large drop but low volume of water
- Low head has a short drop but higher volume of water
What new technology is there for HEP?
- Kaplan turbines, which rotate with the flow of water to maximise energy
- Helical turbines, which generate electricity when water flows down them, reducing damage from turbidity and impacts on fish
- Micro-hydro schemes, which are small local dams that block off only part of the river, less effective but more ecofriendly
What does HAWT stand for? Advantage and Disadvantages
- Horizontal Axis Wind Turbine
- Advantages include high efficiency and advanced and well established technology
- Disadvantages include risk of stress cracking, more elevation required and heavy turbines and blades
What does VAWT stand for? Advantages and Disadvantages?
- Vertical Axis Wind Turbine
- Advantages include being able to be driven from any direction, quiet and operation at low wind velocity
- Disadvantages include lack of large scale designs and lower efficiency
What environmental impacts can wind power have?
- Manufacture and installation
- Noise pollution
- Habitat damage
- Bird strikes and Bat Death
What new technologies exist for wind power?
- Blade-tip fins which reduce wind resistance
- Nacelle Brushes, which reduce air escape at the base of the blades
- Helical VAWTs, which have curled blades that rotate more smoothly and efficiently
- Wind Assisted Ships (They put the sails back on ships)
What are the methods of Wave Power?
- point absorber, that rises and falls with the tides
- overtopping, which breaks waves into a container where they flow down back to the sea
- Oscillating surge, which uses the horizontal and vertical movements to rotate a turbine
- Surface Attenuation, a large floating device that pulls and pushes pistons to generate power
What issues are faced by Wave Power equipment?
- They must withstand storms
- They must withstand corrosion
- They must be anchored in some way
- It can be expensive to set up
- It can be expensive to transfer energy from them
What environmental effects can Wave Power have?
Can affect the seabed because of anchoring, but otherwise not much at all
What is typically used as Biofuel?
- Wood
- Combustible Crops
- Alcohol from carb crops like sugar cane
- vegetable oil based biodiesel
- Combustible crop waste
- domestic refuse
- landfill biogas
What are the advantages of Biofuel?
- Supply rate can be controlled
- Can be stored
- oils can replace fuel for cars
- Carbon neutral
- Higher energy density that other renewables
What are the disadvantages of Biofuel?
- Waste biofuel is limited
- Large areas of farmland are needed, increasing land-use conflict
- lower energy density that fossil fuels
- farming techniques may offset carbon neutrality
What new biofuel technologies exist?
- Hydrogen from algae photosynthesis used as fuel
- Anaerobic digestion can produce energy from waste
How can geothermal power be harnessed?
- Heated groundwater from springs or aquifers
- Steam systems that se high pressure steam to generate electricity
- Heating water into steam using hot rocks
What environmental impacts and geothermal power systems have?
- Infrastructure can damage the environment
- Gas emissions released from aquifers
- Contaminated Waste Water
How can Tidal power be harnessed?
- Tidal barrages, a dam across where a lake flows out into the sea, so when the tide changes turbines spin
- Tidal Lagoons that capture and release water to increase tidal flow later
- In-stream turbines that are fixed to the seabed, less efficient but less impact and cost
What environmental impacts can Tidal power have?
- High embodied energy materials
- Changes to tidal patterns
- Increased turbidity and sedimentation
What new Tidal Power technologies exist?
Tidal reefs, which are shorter barrages that allow some water to flow over to allow fish and other aquatic life movement
What is a secondary fuel?
Energy converted into a form that is easier to use than its primary form
What forms of energy can be converted into electricity
kinetic, chemical and light
How does kinetic energy become electricity?
Kinetic energy can move a spinning conductor within a magnetic field
How does chemical Energy become electricity?
When electrons are transferred in a chemical reaction between electrodes
How can electricity be transported?
Underground cables, overhead cables or batteries
Why is hydrogen a secondary fuel?
It can be produced from surplus primary fuel through electrolysis of water
What two ways can hydrogen be used?
Combustion to produce heat used to turn steam turbines or heat buildings
Fuel cells that use an electrochemical process to combine oxygen and hydrogen to release energy and water
What is the Hydrogen Economy?
Storing hydrogen to supplement unreliable energy sources
How can hydrogen be stored? What is the drawback of each method?
- Compressed gas, though it requires energy to compress
- Liquification, which also requires energy for refrigeration and compression
- Metal Hydride Systems, with much larger and heavier tanks that store the same energy as petrol
- Ammonia, requires energy but does not need compression or refrigeration
What can cause fluctuations in energy supply?
- Intermittent energy resources
- Bulk delivery of fuels
- Incidents
What can cause fluctuations in energy demand?
- Weather fluctuations
- Seasonal changes
- Weekday/weekend uses
- day/night fluctuations
- Short term behaviours, like the kettle surge
Why is surplus energy often generated?
- Base-load power stations run 24hrs, despite lower night-time demand, as it is uneconomic to turn them off
- Fluctuating demands lower industrial demand outside of working hours
- Unused electricity can lose power through heat
What types of energy storage methods exist?
- Peak Shaving, where water is pumped up hill using energy and then released later to be reconverted
- Chemical Energy stored in batteries
- Compressing gas using energy to be released later
- Heat Energy Storage
- High Volume Storage
- Molten Salt Storage
- Kinetic Energy
How can energy conservation be included in transport design?
- Bulk Transport
- Aerodynamic/hydrodynamic design
- Regenerative breaking
- Reduced Mass Designs
- Solid Wheels that create less friction heat
- Fuel efficiency
- End-of-life design
- Embodied energy
How can energy conservation be included in vehicle use?
- Bulk transport
- Optimum speeds to maximise energy usage and minimise air resistance
- Automatic stop/start
- Integrated/public transport systems
- Driverless cars
How can building design include energy conservation?
- Orientation to increase or decrease sunlight heating/lighting
- Surface area to volume ratio
- High thermal mass materials
- Low embodied energy materials
- Earth sheltered Buildings
- Building insulation
- Ventilation
- Heat Exchangers
What is a heat exchanger?
A system that takes hot stale air out of a building and uses it to heat a pipe of fresh cold air before it enters the building
Name energy management technologies
- Occupancy sensors
- Programmable thermostats
- Water Heat Exchanger
- Hot Water saving methods
- Any low-energy appliance
How can human behaviour be changed to minimise Energy waste?
- Turning off lights when not needed
- Turning thermostats down
- Shutting appliances down instead of using standby
- Only heating water when necessary
- Individual radiator thermostats
What methods of Industrial Energy Conservation are there?
- Heat Recovery (Heat Exchangers)
- Insulated pipes and storage
- High Volume Storage
- Combined Heat and Power (using excess heat)
- Recycling
- Mass Reduction of products
