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DEPARTMENT OF GEOGRAPHY RYERSON UNIVERSITY CGEO 702 TECHNOLOGY & CONTEMPORARY ENVIRONMENTS FOSSIL FUELS, GLOBAL WARMING & RENEWABLE ENERGY Abednego Aryee aaryee@ryerson.ca Major world energy resources Mine exploration and development Significance of mining to Canada Socio-economic and biophysical costs of mining OUTLINE COAL MINING OPERATIONS Open-pit mining/strip mining Underground mining operation SOCIO-ECONOMIC IMPACTS OF MINING OPERATIONS Insecurity of employment Violent explosions Subsidence of underground mines Eg. Chile 33 miners have been trapped NATURAL GAS Biogenic gas Thermogenic gas It can be converted to liquid OIL EXTRACTION Oil now accounts for 37% Oil peaked in 1970 Gulf war 1991, Coalition war 2003 Greenhouse Effect & Global Warming Greenhouse Effect is used to describe the role of CO2 and H20 vapour and secondary gases in holding heat within the atmosphere. What are some of these secondary gases? Carbon dioxide, water vapour and other gases absorb thermal infrared radiation released from the Earth’s surface and lower atmosphere. Human sources of carbon dioxide fall into roughly two major classes: - Fossil fuel combustion - Open forest fires Video: An Inconvenient Truth By Al Gore Identify some of the evidences of global warming. Identify possible benefits of global warming. What are some of the likely issues; - environmental, - economic, and - social Al-Gore: 10 things you can do to stop global warming RENEWABLE ENERGY SOURCES Nuclear Biomass Hydroelectric power Wind energy Solar Nuclear fission involves controlled chain reaction of radioactive isotopes (e.g., U235) Fission: Isotopes are split and release energy used to heat water. Steam drives turbines of electric generators. Fusion: atoms of a form of hydrogen can be induced to fuse together at very high temperatures. Helium is produced as a result of fusion. NUCLEAR ENERGY Nuclear Power Plants in Canada The Pickering Nuclear Plants, Ontario Bruce Nuclear Complex on the shore of Lake Huron in Ontario Gentilly 2 at Bécancour, near Trois Rivières in Quebec St. Lepreau Site, New Brunswick Darlington Site, Ontario, Canada - Air pollution is minimal. When nuclear plants are operating as designed, they emit only minuscule amounts of radiation. - The emit no smoke. - Fissionable fuels may last indefinitely. DISADVANTAGES - Three mile Island in 1979 occurred in Pennsylvania the USA which forced the evacuation of thousands of residents. - The explosion of the Chernobyl in Ukraine in 1986 released huge amounts of radiation. - Cancer-causing radiation poses health problems Nuclear Energy … continued ADVANTAGES Wastes derived Biomass is a rather simple term for all organic material that stems from plants (including algae), trees and crops. Biomass sources are therefore diverse; - Organic waste streams –pig, cow, chicken manure - Crops grown to produce heat, fuels, and electricity (energy plantations) - Domestic and industrial wastes - Residual wood from forestry operations Biomass: Agricultural residues - Wood residues from forestry operations - temperate crop waste - animal wastes (pig slurry and chicken manure) -tropical crop wastes Energy crops - woody crops - ethanol from sugar case - maize, sorghum and miscanthus - vegetable oils (rape methyl ester What are the advantages of Biomass? - It is renewable (sustainable resource) - It is widely available (locally) - It is a cleaner fuel - Biomass wastes; crop residue, scrap wood etc. What are the disadvantages of Biomass? - Quantities of biomass for fuel are limited. - Removal of biomass may deplete soil. - Biomass yields low net energy ADVANTAGES & DISADVANTAGES OF BIOMASS Penstock (pipe) leads to a turbine and builds pressure on the way there The turbine's turning, connected to the generator, also turns multiple magnets located inside it. These magnets rotate past copper coils As a result, AC (alternating current) is Examples of dams are the three Gorges dam in China, James Bay in Canada, Aswan High dam in Egypt etc. HYDROELECTRIC POWER What are the advantages of Hydroelectric Power? - It produces electricity without air pollution - Efficient hydropower can be built at the scale hydropower is based on flow of water. It is renewable What are the disadvantages of Hydro? -Reservoirs can be filled with sediments-laden rivers, reducing the volume needed to generate power. -Large scale hydropower projects (eg. Three Gorges Dam are costly to build. ADVANTAGES & DISADVANTAGES OF Hydroelectric Power Advantages of wind energy - Wind is a perpetual energy source Wind turbines can be installed quickly Wind is a clean source of energy Disadvantages of wind power Intermittent power source Large wind farms are eye sore or pose visual intrusion May pose serous threats to birds Passive solar systems - Passive solar systems often involve architectural designs that enhance the absorption of solar energy Active solar systems - Pumps and other apparatuses are usually used to circulate water, air and other fluids from solar collectors to a heat sink. Photovoltaics This is the term used for the technology that converts sunlight directly into electricity using solid semi-conductor materials. SOLAR ENERGY There are three systems What are the advantages of Solar Power? - Solar is clean and sustainable. - It is a perpetual supply of energy from the sun. - Cost-efficient and portable to use. What are the disadvantages of Solar Power? - Depends on the time of the day, location and period of the year. - Solar panels also pose visual intrusion ADVANTAGES & DISADVANTAGES OF SOLAR ENERGY USING ENERGY MORE EFFICIENTLY RESIDENTIAL SECTOR - Energy-efficient buildings, heating, cooling etc. - More energy-efficient appliances INDUSTRIAL SECTOR - Adopting refinements in industrial processes or products as well. - Producing products from recycled materials - Developing new technologies that reduce energy use TRANSPORTATION SECTOR -Hydrogen-powered vehicles -Efforts should be geared towards the use of fuel-efficient vehicles. COMMERCIAL SECTOR Using centralized heating system will also result in a net dollar savings. - Movement from incandescent light bulb to compact fluorescent light bulb. -The third area of commercial energy is switching to electric motors. ENERGY EFFICIENCY CONT’D
