What is Energy Chapter 22 Energy is work a force acting Energy Resources through a distance Energy is heat the amount of heat required to raise 1g of water 1 C E mc2 in nuclear reactions mass can be converted to energy Units of Energy Renewable Joule 1 kg m2 s2 mv2 KWH 3 6 x 106 joule Calorie the amount of heat required to raise 1g of water 1 C 4 18 j Food Calorie 1000 cal BTU the amount of heat required to raise 1 pound of water 1 F Quad 1015 BTU Solar Direct Photo voltaic Mirror focussing Wind Biomass Hydroelectric Geothermal Non Renewable Nuclear U fission Nuclear Fusion Fossil Fuels Oil Natural Gas Coal Oil Shale Tar Sand 1 Direct Solar Solar Thermal Mirrors focus sunlight to boil water Photo Voltaic Cells Direct conversion to electricity Indirect Geothermal Energy from Earth s Internal Heat Engine Geysers CA Supplies San Francisco New Zealand Iceland Hot Dry Rock Wind Hydro electric Biomass Wood grain sugar trash Fossil Fuels Energy derived from ancient solar Coal Oil Natural Gas Oil Shale and Tar Sand Origin of Fossil Fuels Plants store energy from the sun by photosynthesis CO2 2H2O CH4 2O2 If biomass is buried before re oxidation the reduced carbon is preserved as fossil fuels Burial and compaction separates solid coal liquid oil and gaseous gas fractions Reserves and Resources Reserves are the known amount of a mineral in the ground that is exploitable with current technology and under current economic conditions Resource includes the reserves plus estimated undiscovered deposits Oil and Gas Liquid and solid fractions are mobile and can be trapped by impermeable layers Only in sedimentary rock Most deposits of Paleozoic and Mesozoic origin 60 350 my Search is to look for natural traps 2 Oil and Gas The Future World oil production expected to peak about 2015 Gas production will peak 15 years later Price will increase sharply as production peaks Price will affect size of resource Iraq has 200 billion barrels proven reserves No exploration since 1975 Resource likely to exceed 500 bbl Can produce at 1 50 barrel Oil Shale and Tar Sand Reserves nearly equal total of oil and gas Colorado and Utah have large deposits of oil shale in Tertiary rocks Alberta Canada has large deposits of tar sands 3 Coal Lignite Peat Sub bituminous coal Bituminous coal Anthracite Metamorphic Coal Reserves are very large 10 times that of oil and gas Exploitation may depend on technology to scrub CO2 Scrub CO2 Methane Hydrates Liquefy CO2 and put on ocean Methane CH4 forms an ice like bottom compound with water at oceanbottom P T It is an energy resource larger than known natural gas reserves Will require new technology for extraction Mg2SiO4 2CO2 2MgCO3 SiO2 olivine carbon dioxide magnesite quartz Scrubbing would double price Carbon Dioxide Greenhouse Gases CO2 CH4 Pass Visible light Opaque to Infra red Earth captures energy from sun but cannot re emit Causes warming Colorless odorless tasteless poisonous gas Animal life cannot exist in 1 CO2 Plants love it Current level is about 370ppm Increases at about 1 per year Greenhouse gas 4 Nuclear 235U fission 235U is less than 1 of natural Uranium Can be enriched to 3 3 US light water reactors use water as moderator and coolant Produces about 16 of US electricity and about 7 of total energy consumed No new reactors Size of energy resource is larger than coal 235U Fission 235U US light water Canadian Deuterium moderated High Temperature Gas Cooled reactor Water is moderator Moderator slows Graphite moderated Highly enriched fuel Chernobyl Fort St Vrain neutrons for capture Fuel is UO2 enriched to 3 3 235U Nuclear Other or MOX Fuel produces 3 million times as much energy per gram as fossil fuel Radioactive Waste About half of 235U is consumed Spent fuel rods contain 90Sr and 137Cs plus trans uranics Np Pu Am Cm etc Cs and Sr have 30 year half lives TUs have up to 24 000 year half lives Spent fuel still produces 900 W Ton of power after 10 years Geologic Host Rocks Salt Germany France WIPP High Thermal conductivity Self sealing flows plastically Granite Sweden Good thermal conductivity Stable craton environment Tuff Yucca Mountain Nevada It s in Nevada It s already contaminated 5 Future Technologies Breeder Convert 238U to Pu 238U is 99 of natural U Early attempts were unstable Fusion Nuclear fusion of light elements H He Li Near break even point Size of resource is inexhaustibly large 6
View Full Document
Unlocking...