Environmental Final Flashcards
What are the two main types of energy? Give two examples of each.
Renewable Energy (sunlight, geothermal, tidal) Nonrenewable Energy (oil, coal, natural gas, nuclear)
How does Canada compare to the rest of the world in terms of commercial energy use by source? (Nonrenewable vs Renewable)
Canada: 27% Renewable, 73% Nonrenewable
World: 15% Renewable, 85% Nonrenewable
Describe the global primary supply chart (pie chart percentages).
Oil: 34.4% Coal: 26% Natural Gas: 20.5% Combustible Renewables and Waste: 10.1% Nuclear: 6.2% Hydro: 2.2%
Who consumes more energy, developed or developing nations?
Developed nations (U.S. with 4.4% of world’s population uses 18% of world’s energy; Canada with 0.5% of the world’s population uses 2.6% of world’s energy)
What happened in 2015? (Hint: oil)
Oil priced dropped from $140USD to $30USD per barrel; fracking and newer extraction techniques propelled US into oil and gas exporter; Canadian oil production faltered due to blocking of Canadian exports and CDN falls from $1.06 to $0.68
What is net energy? What ratio is often used to denote this?
Net energy is the difference between energy returned (or acquired) and energy invested to acquire it. Ratio: EROI (Energy return on investment) EROI = usable energy returned/energy invested = ER/EI
What does a high EROI mean? What causes this to decline?
High EROI ratio means we receive more energy than we invest to acquire it. Ratios decline when we extract the easiest deposits first and now must work harder to extract the remaining reserves.
Was U.S. oil production higher or lower than Hubbert’s Peak (Hubbert’s prediction of U.S. oil production)?
Higher
Why has the Arctic gained world attention?
Potential large reserves of undiscovered oil and gas.
What is crude oil? (4 points)
A mixture of hundreds of different types of hydrocarbon molecules
Formed 1.5 - 3 km underground
Formed from dead organic material buried in marine sediments
Transformed by time, heat and pressure.
Refineries separate crude oil into components such as ____, _____ and _____.
gas; tar; asphalt
Geologists map underground rock formations to determine ____ and ____ of petroleum deposits.
size; location
______ _____ ____ reveals the oil that could be extracted with the current technology.
Technically recoverable oil
Define ‘Economically recoverable oil’.
Recognizes the balance between the costs of extraction, transportation and the current price of oil.
Oil that is technologically and economically feasible to remove under current conditions is known as ___________.
Proven recoverable reserve
Define ‘Exploratory drilling’
Small, deep holes to determine whether extraction should be done. (Oil is under pressure and often rises to the surface).
What are primary and secondary extraction?
Primary: The initial drilling and pumping of available oil.
Secondary: Solvents, water or steam is used to remove additional oil; expensive.
Four methods for oil sands extraction
Open-pit mining (only 20% accessible)
Cyclic steam stimulation (not common)
Steam-assited gravity drainage (main focus currently)
Vapour extraction
What are some advantages and disadvantages of heavy oils from oil shale?
Advantage:
- Large potential supply
- Moderate cost (oil sand)
- Efficient distrubution system in place
- Easily transported between countries
- Technically is well-developed
Disadvantage:
- High cost (oil shale)
- Releases CO2 and other air pollutants when burned
- Low net energy yield
- Large amount of water used for processing
- Severe land disruption from mining
- Water pollution from mining
Natural gas is composed of ___ - ___% methane
50-90
Natural gas is removed as liquified _______ gas and shipped as liquified _____ gas.
petroleum; natural
What are some advantages and disadvantages of conventional natural gas?
Advantage:
- Ample supplies (62-125 years)
- Moderate environmental impact
- High net energy yield
- Emits less CO2 and other air pollutants than other fossil fuels
- Low cost (with large subsidies)
- Easily transported by pipeline
- Good fuel for fuel cells and gas turbines
Disadvantage:
- Nonrenewable resrouce
- Releases CO2 and other air pollutants when burned
- Methane (a greenhouse gas) can leak from pipelines
- Difficult and costly to transport from one country to another
- Shipped ascross the ocean as highly exposive LNG (liquified natural gas)
- Requires pipelines(?)
What is shale gas?
Natural gas trapped in sedimentary rocks. Removed by hydraulic fracturing (fracking).
Describe fracking.
Drill well and inject pressurized fluid or gas to fracture rock
Fluid pumped into cracks (usually water mixed with sand and additives)
Sand keeps the crack open after pumping
Natural gas collected