Post on 27-Dec-2015
The Need for Energy- fuel: any substance from which energy is obtained.
- Examples:?- How have things changes?- Organic fuels: contain carbon compounds, examples:- Hydrocarbon: compounds composed of only hydrogen and
carbon, example: methane (a lot of them end in “ane”- Methane, Ethane, Octane…. The octane rating of gasoline is
derived from a formula based on the amount of energy contained in the gas compared to pure iso-octane.
- Organic fuels often contain other chemicals (the bad part usually for us anyhow), example: sulfur or lead
- Called impurities, many contribute to pollution.
Fossil Fuels- When organisms die, not all of the energy they had stored
was released.- When buried, and you add pressure, typically the organisms
energy is not loss.- Therefore: fuels derived from the remains of organisms that
lived long ago are fossil fuels. Examples: coal, petroleum, and natural gas.
Coal- Generated by organisms that died, covered in sediment, and with added pressure and heat
formed coal.- Chemically changed, and water removed (via pressure) become solid rock (coal)- Over time, hydrogens and oxygen's are removed, concentrating the carbon
(concentration of coal is directly related to the amount of energy available).- This concentration is how we categorize different types of coal materials.
Peat- Not technically a type of coal- Lowest value of energy available- High water content, low percent of carbon- First stage of coal formation- Looks kind of like decaying wood- The youngest of these categories- Gives off a large amount of smoke (due to high water concentration)
Lignite- Second stage of coal formation- Soft, brown coal composed of about 40% carbon- Burns quickly, very little smoak- Must be mined (peat does not have to be mined)
Bituminous Coal- Soft coal, 85 % carbon- Must be mined- Even more pure, burns hotter- Used by many power plants- Most abundant coal mined in US
Anthracite - Purest coal, 95% carbon- Shiny, black, often deeper underground than any other- Burns the hottest, least amount of smoke- Most expensive to acquire as well.
Petroleum - crude oil, and a liquid fossil fuel- non-renewable- Formed from microscopic protists, plants, and animals- Millions of years to form- Trapped in pocked beneath nonporous rock (with water and natural gas)- Can be under very high pressure (hence the term “gusher” when drilled into it.- Worlds most important resource.- Used to make a variety of products after being refined
- Heat homes- Produce electricity- Grease and lubricants- Asphalt for roads- Many types of plastics
Natural Gas- Often found trapped above petroleum pools- Mostly gaseous hydrocarbons- Methane is the primary- Others include: propane, nitrogen, and helium- Used instead of coal or oil because it burns cleaner (stoves, heaters,
etc…)- Really good because it does not have to be converted to electricity,
can be burned directly- Because of this, more efficient and less expensive to use- Often NG is considered a waste product at the oil platform and is
burned off.
Other organic fuelsBiomass Fuels (is a fuel formed from the products of living organisms)Wood- Still relied on heavily in developing nations- Advantages: renewable- Disadvantages: lots of smoke that is high is carbon dioxide, tree reduction can cause more
erosion.Garbage- About 2/3 of the material in garbage can be burned.- Some cities in the US already take advantage of this (using the heat to generate steam, thus
produce electricity)Methane- “swamp gas”- Decaying garbage dumps also produce methane (both are being harvested and used same
ways as natural gas)- Cows are the number one releasing agent of methane (both ends) but this is much harder to
use.