Uses by sources


"Energy Resources" is NOT the same thing as "Types of energy".

"Types of energy" means "kinetic energy", "chemical energy" and so forth.

"Energy Resources" is about ways of getting energy so we can generate electrical power.

You'll need to know:
- the names of the energy resources in these pages
- how each one works
- the advantages & disadvantages of each
- which ones are renewable



Primary energy sources

Primary energy sources are substances or processes with concentrations of energy at a high enough potential to be feasibly encouraged to convert to lower energy forms under human control for human benefit. Except for nuclear fuels, tidal energy and geothermal energy, all terrestrial energy sources are from current solar insolation or from fossil remains of plant and animal life that relied directly and indirectly upon sunlight, respectively. And ultimately, solar energy itself is the result of the Sun's nuclear fusion. Geothermal power from hot, hardened rock above the magma of the Earth's core is the result of the decay of radioactive materials present beneath the Earth's crust.

Fossil fuels

Fossil fuels, in terms of energy, involve the burning of coal or hydrocarbon fuels, which are the remains of the decomposition of plants and animals. There are three main types of fossil fuels: coal, petroleum, and natural gas. Another fossil fuel, liquefied petroleum gas (LPG), is principally derived from the production of natural gas. Heat from burning fossil fuel is used either directly for space heating and process heating, or converted to mechanical energy for vehicles, industrial processes, or electrical power generation.

Nuclear energy

Nuclear power stations use nuclear fission to generate energy by the reaction of uranium-235 inside a nuclear reactor. The reactor uses uranium rods, the atoms of which are split in the process of fission, releasing a large amount of energy. The process continues as a chain reaction with other nuclei. The energy heats water to create steam, which spins a turbine generator, producing electricity.

Renewable sources

Renewable energy is an alternative to fossil fuels and nuclear power, and was commonly called alternative energy in the 1970s and 1980s.

Biomass, biofuels, and vegetable oil

Biomass production involves using garbage or other renewable resources such as corn or other vegetation to generate electricity. When garbage decomposes, the methane produced is captured in pipes and later burned to produce electricity. Vegetation and wood can be burned directly to generate energy, like fossil fuels, or processed to form alcohols.

Geothermal energy

Geothermal energy harnesses the heat energy present underneath the Earth. Two wells are drilled. One well injects water into the ground to provide water. The hot rocks heat the water to produce steam. The steam that shoots back up the other hole(s) is purified and is used to drive turbines, which power electric generators. When the water temperature is below the boiling point of water a binary system is used. A low boiling point liquid is used to drive a turbine and generator in a closed system similar to a refrigeration unit running in reverse.

Hydroelectric energy

In hydro energy, the gravitational descent of a river is compressed from a long run to a single location with a dam or a flume. This creates a location where concentrated pressure and flow can be used to turn turbines or water wheels, which drive a mechanical mill or an electric generator.

Solar power

Solar power involves using solar cells to convert sunlight into electricity, using sunlight hitting solar thermal panels to convert sunlight to heat water or air, using sunlight hitting a parabolic mirror to heat water (producing steam), or using sunlight entering windows for passive solar heating of a building.

Tidal Power Generation

Tidal power can be extracted from Moon-gravity-powered tides by locating a water turbine in a tidal current, or by building impoundment pond dams that admit-or-release water through a turbine. The turbine can turn an electrical generator, or a gas compressor, that can then store energy until needed. Coastal tides are a source of clean, free, renewable, and sustainable energy.

Wind power

This type of energy harnesses the power of the wind to propel the blades of wind turbines. These turbines cause the rotation of magnets, which creates electricity. Wind towers are usually built together on wind farms.

Energy development

Energy development is the ongoing effort to provide sufficient primary energy sources and secondary energy forms to fulfill civilization's needs. It involves both installation of established technologies and research and development to create new energy-related technologies. Major considerations in energy planning include resource depletion, supply production peaks, security of supply, cost, impact on air pollution and water pollution, and whether or not the source is renewable.

Technologically advanced societies have become increasingly dependent on external energy sources for transportation, the production of many manufactured goods, and the delivery of energy services. This energy allows people who can afford the cost to live under otherwise unfavorable climatic conditions through the use of heating, ventilation, and/or air conditioning. Level of use of external energy sources differs across societies, as do the climate, convenience, levels of traffic congestion, pollution, production, and greenhouse gas emissions of each society.

Expanding human populations generally require an increased consumption of and dependence on external energy sources. Research, development and practice of energy efficiency and conservation by the populace allows a degree of mitigation of this dependence. Wise energy use embodies the idea of balancing levels of human comfort and energy consumption by researching and implementing effective and sustainable energy harvesting and utilization measures.


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