Module 3: Non-Renewable Energy Sources

Primary Energy

• Sources are those that are either found or stored in nature

• e.g. coal, oil, natural gas and biomass

• nuclear energy, thermal energy, potential energy

• can be used directly

• these sources are converted into electricity

Secondary Energy

Resources are those forms that must be produced by conversion of primary sources (e.g. steam and electricity)

Renewable Energy

• Energy obtained from sources that are essentially inexhaustible

• Examples are wind power, solar power, geothermal energy, tidal power, hydroelectric power - mostly biomass based and are available in unlimited amount in nature

• can be harnessed without the release of harmful pollutants

Non-Renewable Energy

• are available in limited amount and develop over a longer period of time.

• e.g. conventional fossil fuels such as coal, oil and gas, and nuclear power which are likely to deplete with time

Fossil Fuels

• The product of natural changes in organic materials over millennia.

• It is a general term for buried combustible geologic deposits of organic materials formed from decayed plants and animals by exposure to heat and pressure in the earth’s crust.

• When __________ are burned, carbon and hydrogen react with oxygen in air to carbon dioxide (CO₂) and water (H₂O)

• Electricity is generated by transforming mechanical energy (heat) to electrical energy in a turbine or generator

Coal

• It is formed over millions of years by decay of land vegetation

• It is the most abundant on Earth

  • U.S., Russia, China, Australia, India, Germany, South Africa have largest deposits

  • U.S. has 25% of world’s coal deposits

  • 100+ years’ reserve

Surface Mining

What type of coal mine is this?

• Coal within 30 m of the surface

• Reached by removing soil, subsoil, and overlying rock strata

• 60% of U.S. coal is obtained this way

• Usually safer for miners, less expensive

• Disrupts the land extensively

• Strip mining—one type of surface mining

  • Vegetation, soil, and rock are ‘stripped away’

  • Trench is dug to extract coal

  • Rubble dumped into nearby valleys

Subsurface Mining

What type of coal mine is this?

• The extraction of mineral and energy resources from deep underground deposits.

• Approximately 40% of coal is mined this way in the U.S.

False - It contributes more air pollutants than oil or natural gas

Coal burning

• Contributes less air pollutants compared to oil or natural gas

• Coal burning electric power plants produce 1/3 of all airborne mercury emissions

• When coal is burned it produces sulfur and nitrogen oxides, which react with water in the atmosphere and cause acid deposition

• Releases more CO₂ into the atmosphere (per unit of heat produced) than other fossil fuels

Natural Gas

• It is a gaseous fossil fuel that is versatile, abundant and relatively clean compared to coal and oil.

• More evenly distributed than oil supplies.

• Natural gas mainly consists of methane (CH4).

• Natural gas is highly compressed in small volumes at large depths in the earth.

Methane, ethane, propane, butane, isobutene, and pentane. It has wet natural gas - if it contains hydrocarbons in addition to methane

What are the energy components of natural gas?

Carbon dioxide, nitrogen, hydrogen sulfide, and water. It has dry natural gas - gases other than methane are removed

What are the non-energy components of natural gas?

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