Chapter 13

Exam 3

Industrial Revolution (late 19th century)

machinery and mass production

Information Age (1980s – present!)

growth of digital technology

Engines:

Converted into mechanical energy on-site

Electric power:

Converted into an electric current

• Delivery of energy over longer distances!

• Higher efficiency

What supply the majority of energy supply and electricity?

Fossil fuels

Fossil fuels

• Hydrocarbon compounds formed from organic matter

• High energy density: released chemical energy by combustion

  • Bituminous coal: 30 kJ/g

  • Petroleum: 46 kJ/g

  • Wood: 15-20 kJ/g

Reserves

Where hydrocarbons are stored impacts their accessibility

Proven reserves

accessible and profitable given current technology

Conventional reserves

easiest to access using standard technology

Oil and natural gas are impacted by

permeability

Coal occurs in

specific rock layers

Remaining conventional oil reserves:

• 1.7 billion barrels of oil (~40-50 year supply)

• 7.5 quadrillion cubic feet of natural gas (~50 year supply)

• 1.1 – 1.2 billion short tons of coal (~130 years)

Unconventional reserves

require new technologies or greater difficulty to extract

Economic viability is also an important factor:

Coal

Hydrocarbons from decayed plant material in ancient swamps

• Most 300-400 million years old (Carboniferous)!

• Formed with pyrite (Fe2S), other metals (mercury, lead, sodium)

Types of Coal:

• Anthracite

• Bituminous

• Lignite

Anthracite

metamorphic heat and pressure

Bituminous

moderate pressure from burial (most abundant)

Lignite

lowest grade of pressure; compressed peat

Coal mining

Used to access conventional reserves of coal

• Underground mining

• Strip mining

Underground mining

removal of deep coal using mine shafts

Strip mining

removing surface deposits to mine coal layers

• May result in “mountaintop removal”

Coal mining affects

• Higher runoff

• Landslides / mass wasting

• Acid mine drainage – water, oxygen react with compounds in mined material

  • Sulfur minerals (pyrite, Fe2S)

    • forms sulfuric acid

Petroleum and natural gas

Form from carbon-rich, insoluble sediments called kerogen

Types I and II Kerogen

Formed from algae and plankton (→ Liquid petroleum)

Type III Kerogen

Formed from soil humus, plant matter (→ Natural Gas)

Drilling

• Used to access underground petroleum and natural gas

• Most accessible reserves sit under pressure

• As reserves empty, must be pumped

Types of Drills

• Derricks

• “Horsehead” pump

Oil refineries

remove water, sulfur, nitrogen, metals, natural gas

• Distill into different forms – diesel, gasoline, jet fuel, refined oil

• 6,000 oil-based products from byproducts:

  • Asphalt, plastics, fertilizers, food additives (dyes, artificial sweeteners), and much more!

High demand for crude oil means

that the economy is very sensitive to reduced production and higher prices

“Peak oil”

theoretical point at which oil production begins to decline

• Theorized to be when half of reserves are depleted

• Estimates 2010-2030!

We have not reached “peak oil” due to

technological changes

• Increased efficiency, unconventional reservoirs

  • Hydraulic fracturing

Unconventional oil reserves

• Deepwater oil

• Oil sands

• Oil shale

Deepwater oil

oil rigs in ocean deeper than 1,000 ft.

Oil sands

Bitumen in loose clay and sand; altered former oil deposits

• Refined to form synthetic crude oil

Oil shale

shale rock containing kerogen

• Majority is contained within U.S. deposits

• Potential for hundreds of billions of barrels of oil

• Needs heating and processing with hydrogen to form petroleum

• Small-scale use

Fossil fuel uses

Versatile uses with a high energy density

• Engines – vehicles, equipment

• Generators – local power generation

• Steam boilers – generate radiative heat and hot water

• Power plants – burned to generate power for an electric grid

• Byproducts for industrial uses (plastics, asphalt, etc.)

Consequences of fossil fuel use

Dependence on imports

• Fossil fuels are not evenly distributed!

• Sensitive to type of oil

  • Many U.S. refineries cannot process new U.S. oil reserves!

• Sensitivity to disruption

  • 1970s oil crisis: embargo against U.S. by oil exporting nations in middle East

  • Modern day: supply interruption in the Strait of Hormuz!

Greenhouse gases

Released carbon from

• Carbon dioxide (CO2) from combustion

• Methane (CH4) from extraction sites

Air pollutants

contribute to respiratory issues, smog, acid rain

• Sulfur dioxide (SO2)

• Nitrogen oxides (NOx)

• Particulate matter (PM)

Sulfur dioxide (SO2)

from sulfur compounds produced by anaerobic decomposition

• Highest in coal

Nitrogen oxides (NOx)

Heating of nitrogen and oxygen in atmosphere

Particulate matter (PM)

from incomplete combustion

Clean Air Act:

Enabled U.S. EPA to limit emissions of six pollutants (carbon monoxide, lead, NOx, SO2, particulate matter)

Technologies capture pollutants in exhaust before emission:

• Electrostatic precipitators

• “Wet scrubbers”

• Carbon capture

Electrostatic precipitators:

use electric charge to capture particles

“Wet scrubbers”:

liquid droplets capture pollutants in exhaust

Carbon capture:

use solvents or filters to capture carbon from exhaust, store underground