Smart Tools

Classroom Tools Series:

Science Resources 2 – Energy

After a hard day’s work, you find yourself physically drained and when people ask what has happened to you, all you can say is that you’ve lost your energy. For a layman, it is easy to understand that what you mean is you’re tired. But talking to a scientist or at least to somebody with a scientific inclination, the word “energy” totally means different.

In the various branches of science, energy has distinct definitions. For example, in Biology, the energy as the ability to do work makes no sense when it is actually a fundamental element for sustaining life when transformed from greater to lesser concentrated structures. In Chemistry, the energy’s spontaneous exchange and transformation with the environment is in fact the cause and effect of all chemical transformations (decomposition, synthesis, or a reaction of molecules or atoms) that a substance can undergo. In Physics, there is a precise mathematical definition of energy as the amount of work itself or the force applied through a distance.1

But how exactly did energy come about?

“The sun was the first energy source.”  This is according to the Elementary Energy Infobook of The NEED Project, which presented the history of energy in pdf format.

In the Milestones of the History of Energy and its Uses, it claims that “fire was civilization’s first great energy invention, and wood was the main fuel for a long time.”2 In their site, they featured links to several energy timelines on the different energy sources like coal, electricity, geothermal, natural wind, nuclear power, and a lot more. In addition, significant events were also highlighted even before the 1600’s down to the 1900’s.

Resources

There are two sources of energy: renewable and non-renewable. Renewable sources are those which are inexhaustible or limitless like solar, wind, geothermal, biomass, hydro, and ocean, while non-renewable sources are just the opposite: those which can be used up or depleted like oil (petroleum), natural gas, coal, and uranium (nuclear).3 These main sources can also be used to produce secondary sources of energy which include electricity and hydrogen.4

Energy and the Environment

The Canada Science and Technology Museum site has listed effects of the different energy sources in the environment.5

  • Petroleum

    • Contribution to the greenhouse effect is one of the hazards of this energy source when carbon dioxide is released in the combustion of fossil fuels including petroleum. Carbon monoxide, certain hydrocarbons, and “other gases released in this way may be toxic and/or carcinogenic.” Other concerns include massive oil spills caused by petroleum transportation.

  • Coal

    • Like petroleum, coal combustion emits gases that contribute to the greenhouse effect, as well as to the formation of acid rain that is harmful to both nature and infrastructures. Good thing is scientific ways to effectively control acid gas emissions are now being utilized and other means are still being developed to reduce these harmful emissions.

  • Natural Gas

    • The least harmful fuel and proves to be very useful too.

  • Nuclear energy

    • A subject of heated debates, nuclear fuel actually requires very little space. How little? The size of a volleyball is enough to provide a person all the energy he needs to last him a lifetime! And it produces no air pollution…just the production of long-life radioactive wastes.

  • Hydro-electricity

    • Flooding of lands, release of mercury in the soil and use of PCBs are the dangers of this energy source.

  • Wind and solar energy

    • Absolutely no wastes are produced! Just requires an enormous space for windfarms and solar batteries that results in “visual pollution”, according to the author.

  • Geothermal energy

    • Minor effects like noise pollution and change in local climate due to the release of heat, but there is also “the potential release of gas or water containing toxic products from underground deposits.”

  • Biomass Energy

    • Global warming due to plant combustion, increased in greenhouse effect because of the reduction of the number of plants that can absorb carbon dioxide.

Energy Crisis

Wikipedia defines energy crisis as “any great shortfall (or price rise) in the supply of energy resources to an economy. It usually refers to the shortage of oil and additionally to electricity or other natural resources.”6 This is basically what every nation is experiencing today. With the imminent depletion of fuel deposits, prices shoot up especially given the inelastic demand for these products and everybody can’t seem to do anything about it for now.

Know more about historical crises7 and saving energy by clicking on the links.

Sources:
1Energy, http://en.wikipedia.org/wiki/Energy
2Milestones of the History of Energy and its Uses,
http://www.eia.doe.gov/kids/history/timelines/index.html
3, 5Background Information for Energy,
http://canadaonline.about.com/gi/dynamic/offsite.htm?site=http%3A%2F%2Fwww.sciencetech.
technomuses.ca%2Fenglish%2Fschoolzone%2FInfo_Energy.cfm
4Sources of Energy, http://www.eia.doe.gov/kids/energyfacts/sources/whatsenergy.html
6, 7 Energy Crisis, http://en.wikipedia.org/wiki/Energy_crisis
8Saving Energy, http://www.eia.doe.gov/kids/energyfacts/saving/index.html