Enduring Understanding:

• Humans use energy from a variety of sources, resulting in positive and negative consequences.

Learning Objective:

• Identify types of fuels and their uses.

Essential Knowledge:

• Wood is commonly used as fuel in the forms of firewood or charcoal.

  • It is often used in developing countries because it is easily accessible.

• Peat is partially decomposed organic material that can be burned for fuel.

• Three types of coal used for fuel are lignite, bituminous, and anthracite.

  • Heat, pressure, and depth of burial contribute to the development of various coal types and their qualities.

• Natural gas, the cleanest of the fossil fuels, is mostly methane.

• Crude oil can be recovered for tar sands, which are a combination of clay, sand, water, and bitumen.

• Fossil fuels can be made into specific fuel types for specialized uses (e.g., in motor vehicles)

• Cogeneration occurs when a fuel source is used to generate both useful heat and electricity.

Wood and Charcoal

• Primarily used in developing countries

• One of the oldest methods of energy production

  • Used ever since humans first started making fires

  • Charcoal is made from wood, and requires some processing/more steps

    • The benefit, however, is that it burns hotter

• Readily accessible and renewable if used sustainably

• The removal of trees for energy can cause soil erosion

  • This then leads to food security issues

• Deforestation can decrease the amount of precipitation and CO2 sequestration

Peat

• Partially decomposed organic material that can be burned as fuel

• Would eventually turn into coal if given enough heat, time, and pressure

• Using these fuels inside without proper ventilation can cause indoor air pollution and health problems

Coal

• Peat turns into lignite coal

  • This has a low heat capacity, low sulfur, and high moisture content

  • Least valuable, is not as concentrated as the other types of coal

  • Has many impurities and moisture so will produce smoke

• Lignite turns into bituminous coal

  • Most commonly used, high heat capacity, high sulfur

  • Will release the most sulfur into the atmosphere (pollution, can cause acid deposition when mixed with water)

• Bituminous turns into anthracite coal

  • Best quality, high heat capacity, low sulfur content

  • Takes the longest to make

  • Has the least amount of impurities

• All coals will release impurities but some have less than others

Natural Gas

• The cleanest fossil fuel

  • It doesn’t release much emissions

  • Very little sulfur, mercury, lead, etc.

• It still produces CO2, just not other impurities

• This is mostly methane

• Natural gas is very light and is very easy to transport/distribute

  • Doesn’t need to go through tankers, warehouses, trains, etc.

  • Escape from pipes can be a concern, however

Oil

• Crude oil can be extracted from tar sands, which are a combination of clay, sand, water, and bitumen

  • Tar sands are not an ideal method of sourcing oil, but because other sources are being depleted we have to turn to this

  • We have to remove many other things in the sand to get to the oil which costs time, energy, and money

Refined Crude Oil

• Crude oil and other fossil fuels can be made into specific types of fuels for specialized uses

  • Such as gasoline, diesel, jet fuel, heating oil, etc.

• Refineries are the location where this is done, and take advantage of different boiling points to make different fuels

Cogeneration

• Occurs when a fuel source is used to generate both useful heat and electricity

• The heat that may be a byproduct of the electrical energy production can be used in other areas such as heating homes or water

• This is more efficient, using all parts of the energy instead of letting the heat just dissipate into the world