Chapter 26 Energy Resources

1. Chapter 26 Energy Resources 4-24-14 start

2. Traditional Energy Sources • Fuel – materials that are burned to produce heat or power • Include renewable resources such as wood, field crops, dried fecal material • Any material that burns

3. Wood • Used as primary energy source in 4% of US households • Mostly used for lumber and paper in U.S. • 1.5 billion ppl use it throughout the world for heating and cooking • Leads to deforestation

4. Field Crops • Corn, hay, and straw some burn directly • Residue left after a harvest is also used as fuel • Mostly used on farms and in houses

5. Fecal material • Contains undigested pieces of grass that helps burning • People in developing countries collect animal dung for fuel and dry it outside of their stables

6. Peat • Bog formation: http://water.epa.gov/type/wetlands/bog.cfm • Plant material that is compressed by the weight of water and other sediments, becomes light, spongy material • Several 1000s yrs old • Highly decomposed peat burns with greater fuel efficiency than wood

7. Fossil Fuels • Energy sources form over geologic time as a result of compression and partial decomposition of plants and other organic matter • Ex. Coal, natural gas, petroleum

8. Coal • Classified by the amount of pressure under which it is formed and the amount of time involved (formation of peat is first step to coal formation) • Anthracite – most efficient and most cleanly burning coal

9. Coal Formation http://www.uky.edu/KGS/coal/coalform.htm

10. Petroleum and Natural Gas • Petroleum • Petra – rock • Oleum – oil • Natural crude oil found underground that oozes upward

11. Obtaining energy resources Compare the following: • Harvesting: peat & wood • Mining: coal & uranium/plutonium • Drilling: oil & natural gas • What are the negative environmental effects of using each for energy?

12. Section 26.2 Alternative Energy Resources 4-28-14

13. Solar Energy • Passive Solar Energy • Concrete, adobe, brick, stone, or tile can capture sunlight during the daytime and release it at night • Can provide 70% of energy to heat house

14. Active Solar heating • Collectors & solar panels - absorb solar energy • fans or pumps - distribute that energy throughout the house

15. Solar Cookers • Used where fuels are scares or expensive • Can be as simple as an enclosed box with reflectors to direct sunlight

16. Photovoltaic cells • Thin, transparent wafers made up of layers of boron and phosphorus-enriched silicon • When sunlight hits the cell, it releases electrons (e-) which create an electrical current • Produce small amount of energy • Can be stored in batteries

17. Energy from Water • Water from waterfalls is diverted into massive turbines creating electricity • Turbines turn, driving a generator and producing electrical energy – called hydroelectric power

18. Hydroelectric Power • 20% of worlds energy • 6% of total energy • Nonpolluting

19. Wave Energy • Produces kinetic energy from wind, and used to generate electricity • Renewable and nonpolluting (although barriers in the water can disrupt ecosystems)

20. Geothermal Energy • Energy produced by naturally occurring steam and hot water • Old Faithful • Used to heat homes and businesses

21. Advantages Abundant and reliable at site where occurs Pollution free Disadvantages As water heated this way is tapped, cooler water replaces it Can disrupt ecosystems Transport not practical Geothermal Energy

22. Wind Energy • Wind turbines that convert the energy of the wind to mechanical energy, then used as electrical energy • Most in U.S. located in California • Environmentally friendly but can disrupt ecosystems and most practical in areas with steady winds

23. Quick Chemistry Review • Elements – substances that cannot be broken down into smaller substances by chemical or physical means • Atoms – smallest particle of an element • Made of protons, neutrons, and electrons • Protons and neutrons are housed in the nucleus of an atom • Electrons are negatively charged particles surrounding the nucleus

24. Nuclear Energy • Fission – heavy nucleus (mass number greater than 200) divides to form smaller nuclei and one or two neutrons – this process releases energy! • Doesn’t produce CO2 or other greenhouse gases • Uranium does this (it is radioactive) • Poor mgmt, high costs, poor designs, & disposal concerns contributed to nuclear power decline

25. Biomass • Renewable energy resource produced by living and recently dead organisms • Fuels include wood, dried crops, dried fecal matter

26. Biogas • Mixture of gases that includes methane and CO2 gas • Plant and animal waste converted into digesters then used as fertilizers

27. Section 26.3 Conservation of Energy Resources

28. Energy Efficiency • Use of energy resources in the ways that are most productive • Type of conservation

29. Improvement • Recycle old appliances and vehicles, purchase newer, more energy-efficient models • Adding insulation, installing solar panels, installing new windows

30. Getting more for less • 43% of energy used by motor vehicles and to heat homes and businesses are wasted • Replacing incandescent light bulb with fluorescent

31. Cogeneration • Production of two usable forms of energy, such as steam and electricity, at the same time from the same process

32. Improving efficiency in transportation • Use of fuel-efficient cars • Lower speed limits • Public transportation • Carpooling • Home-based jobs • Bicycles

33. Improving Efficiency in Industry • Improving machinery • Reduce usage of materials and energy used to produce these materials

34. Increasing Efficiency at Home • Energy-efficient appliances • Fluorescent light bulbs • Insulation • Insulating pipes and water heaters • Solar heating

35. Sustainable Energy • Global management of Earth’s natural resources to meet current and future energy needs without causing environmental damage