Energy and the Environment Flashcards
Define fossil fuels
Non renewable forms of energy such as coal, natural gas and oil
How are fossil fuels changing global temperatures
They release carbon back into the atmosphere
Different types of fossil fuels formed depending on:
- The combination of animal and plant debris
- The temperature and pressure
- Length of time the material was buried
Explain the process of coal forming
- Decomposing vegetation from the Carboniferous period is buried under layers of sediments
- Sediments keep the matter out of oxygen and pressure and temperature increasing cooks the matter
- First peat is formed which consists of partially decomposed vegetation including the roots and branches
- Then the peat is heated and compressed turning into lignite, which contains more carbon than peat- still a high content of decayed wood
- Then, with increased temperatures, pressure and time, sub-bituminous coal is formed, followed by bituminous
- Finally anthracite is formed- hardest, produces the most heat, contains the most carbon
How is coal and acid rain connected?
In some areas, coal formed in swamps that were covered by seawater containing large amounts of sulfur. When burned, this pollutant releases which combines with rainwater to turn into weak sulfuric acid that falls as acid rain
Explain the process of oil and natural gas forming
- Organisms that lived in the water fell to the bottom of the sea and were buried under layers of mud
- Due to the lack of oxygen, they did not decay rather accumulated in a layer of mud rich in organic matter
- Over time, the increasing temperature and pressure cooks the matter forming oil
- The high temperatures (100-160 c) break down the matter into chains of hydrocarbons which form oil and natural gas in the source rock
- Since they are less dense than water, they rise up through the porous rocks or they get trapped under an impermeable rock layer and collect in reservoirs
Where is oil and natural gas found?
Sedimentary rocks
What are 2 unconventional sources used to produce oil?
- Shale rocks- They are hydraulically fractured/ ‘fracked’
2. Tar sands- Dug out from the soil and processed
4 different ways oil is trapped
- Anticlinal
- Fault
- Oil traps on salt dome flanks
- Stratigraphic
Define energy mix
The range of sources a country uses to generate electricity
Advantages and Disadvantages of oil and natural gas
A:
Easy to store and transport
Reliable and can respond quickly to demand
Provides employment
D:
Finite+Non renewable+ release CO2
Costly to manage and make transportation pipelines
Devastating to the marine environment
Advantages and Disadvantages of coal
A:
Affordable
Easy to burn
One of the most abundant
D:
Finite and non-renewable
Highly polluting- releases greenhouse gases
Mining can be dangerous
Advantages and Disadvantages of Nuclear power
A:
Does not depend on fossil fuels
CO2 emissions are limited
Provides jobs in design, construction, operation
D:
Very expensive to build
Uranium and plutonium are non-renewable
No solution on where to put toxic radioactive waste
Advantages and Disadvantages of Wind power
A:
Clean, renewable
Turbines are cheap to build and operate
Zero emissions
D:
No wind= no power
Windiest places are the most remote (maintenance)
Opposed by people that live nearby
Advantages and Disadvantages of Wave+ Tidal power
A:
Both are clean, renewable
Multiple suitable locations for wave power
Reduce carbon emissions
D:
Can disrupt marine life
Tidal energy is difficult to transport and is intermittent
Nearshore wave farms have a visual impact on the coast
Advantages and Disadvantages of solar power
A:
Easy to maintain
Silent operation+ can be small scale
Renewable, clean
D:
Initial setup is expensive
Intermittent and hard to store
Not quick
Advantages and Disadvantages of geothermal power
A:
Low carbon- reduces CO2 emissions
Low running costs
Reduces reliance on energy imports and fossil fuels
D:
Disruptive drilling operations
High installation costs
Drilling and operations may release harmful gases
Process of nuclear power
Uranium and plutonium create controlled nuclear fission reactions in thermal power stations
Nuclear fission occurs when a neutron splits a uranium atom releasing energy in the form of heat and radiation
A sealed water source is heated to produce steam which turns the turbines
Wave and tidal power energy generation
Harnessing the movement of waves and incoming/outgoing tide
- Nearshore wave power- harnessing the energy as they break
- Offshore wave power- harnessing the movement in deeper waters
- Tidal range power- turbines harnessing the tide as they move past
- Tidal stream power- harnessed by trapping the high tide behind a barrage and then releasing it
Solar power generation
- Photovoltaic- through solar panels
- Concentrated solar power- Using parabolic mirrors to focus solar energy at the top of a tower filled with fluid which will be heated to produce steam
Geothermal power generation
Harnesses the heat from Earth’s crust:
Drills boreholes
Pumps high pressure heated water up to the surface
Converts to steam to drive the generator turbines
The flash steam plants cool the steam into condensing back to the water to repeat
Advantages and Disadvantages of hydro-electric power
A:
No pollution or greenhouse gases emitted
The dam is a multipurpose scheme
Water can be stored and released according to demand
D:
Expensive to build
Can cause conflicts b/w countries where rivers cross
Flood large areas behind them after consumption
Hydro-electric power generation
Uses the power of moving water to turn turbines
- Building dams
- Building run of the river systems
Biofuels
- Biogas- made from decomposing sewage waste, plant waste, landfill sites matter
- Biomass- from wood
- Bioethanol- fermented plant matter to produce. petrol substitute
Advantages and Disadvantages of biofuels
A:
Cheap and renewable
Crops absorb the CO2 when growing
Produced from waste so cheap
D:
Still releases CO2
Land was taken away from food production
Collecting gas in inefficient
Uses of energy
Domestic Industrial Transport Climate Personal and national wealth
Strategies used to conserve energy
- Move the energy mix towards renewable sources
- Reduce consumption through energy-efficient technology
- Develop new energy sources
- Use government policy to reduce energy demand from transport
How can you be energy efficient in the sense of vehicles?
- Increasing fuel efficiency of vehicles
- Making them out of lighter materials
- Taxing old, less efficient, more polluting vehicles
- Moving towards biofuels (biodiesel made from waste)
- Increase the development of hybrid and electric cars
How can the government contribute to turning countries energy-efficient?
- Congestion charge
- Mass rapid transit
- Variable tax rate (10 years upfront when buying a car)
Define fracking
The hydraulic fracturing of gas and oil shale rock.
They fractured by injecting high-pressure chemicals and fluid into wells. The shale rock fractures release the hydrocarbons from that location back to the surface.
How can oil enter marine ecosystems?
- Poorly maintained, old equipment
- If the oil wellhead on the seabed is damaged
- Wind at vulnerable oil rigs
- Corroded, metal fatigue in pipelines
- Accidental collisions
- Oil tanker spills- navigation errors, collisions
Why is there international concern in oil spills
The oil transports by ocean currents
What happens when oil is in the water
It floats on the seawater and spreads creating an oil slick that thins out leading to a thin oil sheen on the water
Impact of oil spills for beaches
- Rocks coated in oil
- Reduction in tourism
- Beach sediments absorb oil
- Toxins accumulated in clams, and crabs- poison foodweb
- Detergents used in clean up
- Tarballs form (sand+oil)
Impact of oil spills for coral reefs
- Coral bleaching
- Reduced photosynthesis
- Reduced fish population
- Detergents
- Reduced growth + death
Impact of oil spills for marine mammals
- Inhale oil while breathing
- Skin/eye irritation
- Food sources damaged
- Choking
- Chemical burns
- Destroys the insulation for fur-bearing mammals which leads to exposure
Impact of oil spills on birds
- Long term population decline
- Oil reduces their feathers’ repelling abilities
- Inability to fly
- Drowining
Steps taken to manage oil pollution
- Ships fitted with GPS tracking system to report oil released in sea, which is now illegal
- Double-hulled oil tankers
- Detergents that break down the oil into small droplets that biodegrade
- Booms which prevent oil from spreading
- Skimmers that skim (collect) oil
- High pressure hoses
- Controlled burning- burn the fresh oil
- Sorbents that absorb the oil
Uses of fossil fuels
- Heat our homes
- Run our vehicles
- Power manufacturing of medicines, cosmetics
- Provide us with electricity
Define energy security
When a country has enough sources of power to cover most, if not all, of its energy needs
