Energy
V. Energy Resources and Consumption (10-15%) Energy Concepts (Energy forms; power; units; conversions; Laws of Thermodynamics) Energy Consumption –History (Industrial Revolution; exponential growth; energy crisis) –Present global energy use –Future energy needs
Fossil Fuel Resources and Use (Formation of coal, oil, and natural gas; extraction/purification methods; world reserves and global demand; synfuels; environmental advantages/disadvantages of sources) Nuclear Energy (Nuclear fission process; nuclear fuel; electricity production; nuclear reactor types; environmental advantages/disadvantages; safety issues; radiation and human health; radioactive wastes; nuclear fusion)
Hydroelectric Power (Dams; flood control; salmon; silting; other impacts) Energy Conservation (Energy efficiency; CAFE standards; hybrid electric vehicles; mass transit) Renewable Energy (Solar energy; solar electricity; hydrogen fuel cells; biomass; wind energy; small-scale hydroelectric; ocean waves and tidal energy; geothermal; environmental advantages/disadvantages)
Energy Concepts
Types: Kinetic Potential
Forms of Energy FORMDESCRIPTION Mechanical There are two types of mechanical energy: potential and kinetic Thermal Heat is the internal energy in substances-the vibration and movement of atoms and molecules within substances Chemical Chemical energy is stored in bonds between atoms in a molecule. Electrical Electrical energy results from the motion of electrons Nuclear Nuclear energy is stored in the nuclei of atoms. It is released by either splitting or joining atoms Electromagnetic Electromagnetic energy travels by waves.
Units Many units are used for measuring energy The most common are: –Joule [1 J = 1 Nm = 1 kg*m2/s2] –BTU (British Thermal Unit = J) –kWh (Kilo-Watt-hour = 3.6 MJ) –cal (Calorie = J)
Law of Thermodynamics First law –Energy cannot be created or destroyed Second law when energy is converted from one form to another, a less useful form results. Energy cannot be recycled to a higher quality. Only 20% of the energy in gasoline is converted to mechanical energy. The rest is lost as heat and is known as low-quality energy.
Energy Consumption History Wood (a renewable energy source) served as the predominant form of energy until the Industrial Revolution Coal (a nonrenewable energy source) during the industrial revolution over took wood Coal was then overtaken by petroleum during the middle of the 20 th century Petroleum continues to be the primary source of energy worldwide Natural gas and coal experienced rapid development in the second half of the 20 th century
Present Global Energy Use Has increased steadily for much of the 20 th century, particularly since the world consumed million tonnes (Mtoe) of oil in total energy –Corresponds to over 82 billion barrels of crude oil burned in saw the first energy consumption decline since 1982, presumably due to global recession
2010 data shows consumption rates are rising again. One of the most notable developments in recent years has been the explosion of growth in energy demand from Asia –Eclipsed North America for the first time in 2003 –This increase in demand came from China and India China has catapulted itself into second place for energy consumption behind the U.S.
The next largest consumers are –Russia –Japan –India –Germany –France –United Kingdom –Ukraine
The U.S. demand is projected to decrease due to continued high oil prices and recent legislation enacted on energy efficiency Total consumption is only one measurement of energy usage, others include per capita energy consumption and energy intensity. Per capita-Per unit of population; per person Energy intensity-is a measure of the energy efficiency of a nation's economy. It is calculated as units of energy per unit of GDP.
GDP- gross domestic product –The total market value of all the goods and services produced within the borders of a nation during a specified period. Even though the world’s total consumption has increased, most individuals use the same amount of energy they used 20 years ago. What can we infer from this statement?
U.S. Energy Usage by Sector
U.S Industrial Energy Use