12. Sustainable Energy In Challanging Environments

What are the two ways energy resources are classified?

Renewable and non-renewable

Renewable resources

Those that can be replenished in a fairly short time period (wind, solar)

Non-renewable resources

Those that cannot be replenished over a period of time short enough to support humans (coal, liquid fuels, natural gas, nuclear fuels)

Energy Use and Issues in Canada

• 6th in the world in terms of energy production

• 6th consumer in the world

• 88% of the energy we produce goes to the US

• Production: Crude oil > natural gas > primary electricity > Coal > gas plant

Primary energy

use measures the total energy requirements of all energy users. Includes secondary energy use.

• Includes the energy required to transform one form of energy into another (e.g. coal to electricity); the energy used to bring energy supplies to the consumer (e.g. pipeline); and the energy used to feed industrial production processes

(e.g. the natural gas used as feedstock by the chemical industries).

Secondary energy

use accounts for the energy used by final

consumers in the economy.

• Secondary energy use includes the energy used to run vehicles; the energy used to heat and cool buildings; and the energy required to run machinery.

Canadian supply generation

• 61.6% HYDRO

• 12.9% NUCLEAR

• 5.7% WIND

How do oil and gas form?

• Organic material accumulates in fine-grained marine sediments

• Sediments are buried and heated

• organic matter converts to petroleum or natural gas

• Oil and gas migrate from source rocks into reservoir rocks (coarser grained, permeable)

Hydrocarbon migration

Oil and gas are less dense than water and therefore migrate upwards, towards earth surface.

Which rocks make good source rocks?

Typically fine-grained, organic-rich sedimentary rocks such as shale, where organic material can accumulate and convert into hydrocarbons.

Which rocks make good reservoirs?

Typically coarser-grained, permeable sedimentary rocks such as sandstone or limestone, allowing for the accumulation and flow of hydrocarbons.

What stops oil and gas escaping at earth’s surface?

Oil and gas traps (petroleum traps):

• prevent oil and gas escaping with an impermeable ‘cap’

Structural traps

Geological structures trap oil and gas (anticlines and faults)

Stratigraphic traps

Results from sedimentation patterns (sandstone lenses, pinchout, unconformities, reefs)

Oil pools

Underground accumulations of oil

Oil feilds

Regions underlain by one or more oil pools

Canadian oil fields

• Western Sedimentary Basin (Alberta)

• Beaufort Sea/Arctic

• Hibernia (east coast)

• Erie basin

Oil Sands

Oil trapped in sandstone

• as solid

Mined rather than drilled

Athabasca Oil Sands, northern Alberta

• 64% Canada’s current oil production

• new technology for extraction

• proven reserves 165.4 billion barrels

• Canada now has 4th highest oil reserves in the world

Recovery from oil sands

Two methods:

• Steam injection (injecting synthetic chemicals into the ground)

• Open pit (digging)

Oil and gas environmental issues

• mining, water use/pollution

• reclamation (exploration, drilling)

• transport – spills, pipelines

• greenhouse gases

Trans Mountain Pipeline

• Proposed in May 2021

• When it's finished, the Trans Mountain

expansion project will twin the existing Alberta-to-British Columbia line and boost the pipeline's capacity from about 300,000 to 890,000 barrels per day.

TMP: Internal ramifications

Large increases in global CO2 emissions and global warming

TMP: National Implications

The scale of the project, transprovincial issues, federal jurisdictions, global trade

TMP: Provincial, regional, and local concerns

Place-specific impacts of the infrastructure required

Ethical issues

• Related to the rights of Indigenous peoples

  • Environmental impact (oil spills and wildlife)

What is coal made of?

• Compacted plant material

• Sedimentary rock

• lignite (brown coal), bituminous coal

• Metamorphic rock - anthracite

• Coal occurs in beds up to 30m thick

• beds close to the surface are strip mined

Where do we find coal in Canada?

B.C., Alberta, Saskatchewan, New Brunswick, Nova Scotia

Coal: Environmental Issues

Air pollutants (SO₂, NOₓ), land reclamation, tailings, waste water