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Chapter 9. Energy Issues: Life and Societies require energy. Sun provides all energy to maintain life. First energy transfer during photosynthesis In “hunter-gatherer” societies, only energy needed was food (plant or plant supported energy). Domesticated plants and animals added energy.
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Chapter 9 Energy Issues: • Life and Societies require energy. • Sun provides all energy to maintain life. • First energy transfer during photosynthesis • In “hunter-gatherer” societies, only energy needed was food (plant or plant supported energy). • Domesticated plants and animals added energy.
Chapter 9 Early cultures used wood to help form new types of societies. • homes • ships • cook food • metallurgy • è humans became “separate” from other animals • è led to first environmental problems (lack of wood from shortage of trees)
Chapter 9 • Vast pools of dead biomass formed “fossil fuels”. Carboniferous Period 275-350 mya • Primary source of energy for machines. • When local supplies of wood diminished coal discovered • Coal lead to “industrial revolution” (in areas that had coal) replaced wood by 1880 as primary energy source: steam power • è moved from rural to urban • è air pollution
Chapter 9 • Oil overtook coal as the primary energy source in 1950’s (in U.S.). è automobile • Federal government encouraged use of oil by building pipelines across the nation. • Pipeline transported oil from field to refineries • Later sold to private industries and converted to carry natural gas • The higher the price of energy the higher cost for goods and service • Countries strive to keep energy costs low
Chapter 9 • World War II helped end economic depression of 1930’s by creating millions of defense jobs. • è much employment, but few consumer goods. • è after war, defense factories switched to consumer goods and fed the pent-up demand. • è automobiles: factories, energy companies, roads
Chapter 9 • [more chasing more] • - 2 car families from luxury to necessity • - more iron ore needed • - more energy needed • - more and better roads • - distant vacations • - suburbs • - labor saving devices were in demand • - agriculture became more mechanized • Economy grew and so did energy requirements.
Chapter 9 Energy Usage: Energy demand will double by 2020. • Industrialized nations use energy: • è 1/3 for residential and commercial • è 1/3 for industrial • è 1/3 for transportation • “Less” developed nations: • è almost all for residential • Developing nations: è most for industrial
Chapter 9 Residential/Commercial • North America: 30% of total (75% for A.C., refrigeration, heating). • India: 90% of total (most for cooking, since most can’t afford energy for other uses).
Chapter 9 Industrial • Quite variable around the globe, depending on resources available. • U.S.: 30% of total. • Many countries use inefficient processes could improve but requires capital investment • Result is energy poor countries still use wasteful industrial methods because can’t afford to change
Chapter 9 Transportation • Quite variable around the globe, depending on level of development. • Mix of public versus private transportation determines energy expenditures. • Automobiles require 4 times more energy per passenger mile than bus or rail.
Chapter 9 Electrical Energy Almost all created through burning of fossil fuels • U.S. per capita demand is 25 times higher than average demand in less-developed countries. (270 times higher than in Nepal - 2 times higher than Europe). • Less-developed nations put more electricity in industrial uses. (25% in developed nations, 55% in Mexico, 70% in South Korea). • Only zero emission vehicle engine is electric—is it a good option?
Chapter 9 Trends in Energy Consumption Oil is our major source of energy • - 39% oil • - 24% coal • - 27% natural gas • - balance is nuclear, hydropower • In US from 1880 to present we have gone from wood to coal to oil to gas • What’s next?
Chapter 9 • 50% of demand from countries in OECD [Organization for Economic Co-operation and Development] • growth is for natural gas • only decline in demand occurs during political turmoil. See chart. • OPEC began 1960, 12 members • Control 75% of world’s estimated reserves