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Energy to Power the World: I What is Energy Photosynthesis Fossil Fuels Kinetic Energy Energy contained in moving objects Examples include your notebook falling down the stairs, your brother falling off the couch, water over a waterfall Potential Energy Stored energy
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Energy to Power the World: I What is Energy Photosynthesis Fossil Fuels
Kinetic Energy Energy contained in moving objects Examples include your notebook falling down the stairs, your brother falling off the couch, water over a waterfall Potential Energy Stored energy Two types: Physical and Chemical Physical: examples include your brother teetering on the edge of the couch, water about to go over waterfall Chemical: Energy stored in chemical bonds. In the foods you eat, gas you burn Energy is the ability to do work
What you need to know about the Universe • Energy and matter are conserved! • Implications: • matter is recycled on Earth (a carbon atom that was once in a Tyrannosaurus Rex could be in your little pinky) • Energy can change forms (potential to kinetic), but will not magnify or diminish itself • 1st Law of Thermodynamics • Energy is spread around as it is converted from one form to another – get less useful energy out than is put in • 2nd Law of Thermodynamics
What you need to know about Energy on the Earth • The Earth’s energy comes from • The sun • The Earth’s internal and gravitational energy • The Sun’s energy powers • the weather • the ocean waves and currents • most living things • your car!
Photosynthesis • Net chemical reaction: • 6H2O + 6 CO2 + solar energy (enabled by chlorophyll) C6H12O6 (sugar) +6O2 • Photosynthesis stores solar energy in chemical bonds • Energy can be used immediately for cellular respiration • C6H12O6 (sugar) +6O2 6H2O + 6 CO2 + released energy • Energy can be stored for millions of years in organic deposits (fossil fuels)
Fossil Fuels • Coal • Oil • Natural Gas
www.coaleducation.org Increasing depth of burial decreases moisture content and improves quality of coal
Coal forming regions The Earth 350 Million Years ago
Vegetation 300 million years ago Plant Fossils of West Virginia Web site:http://www.clearlight.com/~mhieb/WVFossils/Article1.html
US Coal Deposits Note: Few high quality (anthracite) deposits
CS Fig. 21.6 16
Today’s oil is yesterday’s plankton • Small marine and lake organisms live in surface waters • They die, fall to the bottom and get buried into an organic rich sedimentary layer • If geologic processes heat and squeeze these rocks sufficiently, they will create crude oil and natural gas from the fossils • Crude oil and natural gas will migrate toward the surface • Geologic traps must exist to create an oil field
Examples of geologic traps “pumping oil out is like sucking liquid out of a sponge”
CS Fig. 21.9 21
What it has taken the Earth millions of years to form, we will use up in <1,000 years
That pesky second law of thermodynamics! • 1/2 of all the energy in primary fuels is lost during conversion to useable forms • 2/3 of energy in coal is lost in power plant conversion to electricity • 3/4 of energy in crude oil is lost by the time you finish burning it as gas in your car
Energy to Power the World: II • How it’s used, who uses it • How long will it last?
CS Fig. 21.3 27
CS Fig. 21.5 29
CS Fig. 21.4 30
Demographics of Energy Use • The 20 richest countries consume • 80% of natural gas • 65% of oil • 50% of coal • US and Canada have 5% of world population, use 25% of available energy • Each person in US and Canada uses 60 barrels of oil per year – more than an Ethiopian would use in a year • Developed countries that import a large proportion of their fuel have better conservation methods
CS Fig. 21.4 32
Similar to CS Fig. 21.10 36
Similar to CS Fig. 21.13 37
The End of Cheap Oil Campbell and Laherrere Scientific American, 1998 38
Early steady growth in US oil production C & L, p. 78
What oil companies would have you believe • 1,020 billion barrels of oil in reserve that will be just as cheap as it is today • Production can continue at today’s levels for many decades to come
What Campbell and Laherrere would have you believe • Amount of oil in reserve has been distorted • Production will not remain constant for very long • The last bucket of oil is not as easy to remove as the first
Why distort reserves? • Looks good, nobody checks • When countries increase their reserves, they are allowed to export more oil
Hubbert Curve • Flow of oil starts to fall when ~1/2 of crude oil is gone • In 1956, M. King Hubbert of Shell Oil used this curve to successfully predict US peak in production in 1970 C & L, p. 80
Global discovery peaked in 1960 C & L, p. 82 Industry has found 90% of oil that exists
How long will it last? C & L, p. 81 Perhaps more importantly, when will it become expensive?
Major conclusions • US oil production peaked in 1970 • Norway peaking about now • World production will peak this decade! • By 2002, Mid-East will have control over major part of supply
Oil will get expensive! • 1,000 billion barrels left • At 20 billion barrels/year, will last ~50 years • Will start to decline in production within 10 years • Oil shales and tar sands may help ease pain, but will have environmental consequences
"The fundamental driver of the 20th Century's economic prosperity has been an abundant supply of cheap oil.... Middle East share ... is now about 30%. Unlike in the 1970s, this time it is set to continue to rise.... Share will likely reach 35% by 2002 and 50% by 2009. By then, the Middle East too will be close to its depletion midpoint, and unable to sustain production much longer irrespective of investment or desire." C. J. Campbell Oil and Gas Journal, March 20, 2000
The USGS estimates that economically recoverable oil is just 152 days of supply 50