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Pablo Picasso’s Bull . Energy & Environment. Prof. R ajaratnam Shanthini Dept of Chemical & Process Engineering University of Peradeniya, Sri Lanka. Growing energy production / use. Degrading environment.
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Energy & Environment Prof. Rajaratnam Shanthini Dept of Chemical & Process Engineering University of Peradeniya, Sri Lanka
Growing energy production / use Degrading environment The challenge is to balance the growth of energy production / use with the stability of the environment.
Global energy consumption (in million tonne oil equivalent) ln(2) = 26.6 years tdouble= 0.0263 Actual consumption Predicted at 2.63% growth rate since 1965
Global energy consumption (in million tonne oil equivalent) ln(2) = 26.6 years tdouble= 0.0263
Global energy consumption Have we got enough resources to sustain such energy production / use? Does the environment have the capacity to assimilate all the wastes generated by such energy productions and uses?
Global energy consumption by resource (in million tonne oil equivalent) renewables nuclear hydro gas oil coal
World proved fossil fuel reserves Source: BP Statistical Review of World Energy June 2011
World proved fossil fuel reserves Source: BP Statistical Review of World Energy June 2011
World proved fossil fuel reserves Source: BP Statistical Review of World Energy June 2011
Coal production: Strip mining (Mountain top removal mining) Cross-section after mountaintop has been removed Valley filled with spoil Nine men – that is all it takes to bring this mountain low Source: www.wesjones.com/death.htm
Coal production: Strip mining (Mountain top removal mining)
World proved fossil fuel reserves Source: BP Statistical Review of World Energy June 2011
Oil production at very deep ocean Pressure is over 500 atm Depth drilled by British Petroleum is 5.5 km (3.4 mile) below sea level Ocean is black since no sunlight penetrates to these depths
Oil production at very deep ocean 4.9 million barrels of oil was spilled on the Gulf of Mexico. BP was after 50 millions barrel of oil = 63% of global oil use per day = 20% of global energy use per day
World proved fossil fuel reserves Source: BP Statistical Review of World Energy June 2011
Gas production by fracking • 40,000 gallons of chemicals is used per fracking • 8 million gallons of water is used per fracking • Each well can be fracked 18 times • 500,000 active gas wells in the United States
Fossil fuel use Carbon dioxide Global warming Climate change Kyoto protocol Should be watched under parental care etc.
Global energy consumption forecast Source: U.S. Energy Information Administration, 2011
Environmental Kuznets Curve (EKC) Less Greener richer
Environmental Kuznets Curve (EKC) USA sulfur dioxide emissions Source: Ausubel and Waggoner, 2009
Environmental Kuznets Curve (EKC) USA carbon dioxide emissions
Environmental Kuznets Curve (EKC) ??? Is the economic growth in the United States influenced by its fossil fuel-based carbon dioxide emissions? Rajaratnam Shanthini Journal of Sustainable Development Vol. 5, No. 3; March 2012
Causal relationships Rate of change in GDP Rate of change oil price Rate of change in CO2 emissions : short-run causality : long-run causality 1% growth in the GDP is coupled with 3.2% growth in CO2 emissions in the United States.
Global energy consumption forecast Source: U.S. Energy Information Administration, 2011
66 – 69% of heat released by nuclear fuel Energy wasted Nuclear power plant Useful work output Thermal efficiency = Heat input from nuclear fuel = 31 – 34% = for 500 to 1100 MW plant
According to the 2nd Law of Thermodynamics when heat is converted into work, part of the heat energy must be wasted
Highway driving in a typical car Engine losses in fuel energy conversion, in engine cooling and with exhaust gases 69 MJ Driveline losses 5 MJ Fuel Energy 25 MJ Aerodynamic drags 11 MJ 100 MJ 20 MJ (= 3 L of petrol) Rolling resistance 7 MJ 4 MJ Standby Idle 2 MJ Braking Energy for accessories 2 MJ Source: http://www.fueleconomy.gov/feg/atv.shtml
Bioethanol production from sugar sugar cane residue sugar cane sugar cane crushed and soluble sugar washed out yeast / bacteria Fermentation of sugar CO2 5 – 12% ethanol distilled to concentrate to 80 – 95% ethanol dehydrate to 100% ethanol can’t be used as petrol additive but as petrol replacement can be used as petrol additive Dehydration in an expensive process
Bioethanol production from starch Liquification (at 90 – 95oC; pH = 4 - 4.5; 400 rpm) starch + water + enzyme Saccharification with another enzyme (at 55 – 65oC, pH = 4 - 4.5) Cooling (32oC) Fermentation (40 – 50 hrs) Distillation Dehydration 80-95% ethanol 100% ethanol
biodiesel fuels J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Global warming potential of biodiesel fuels J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Global warming potential of biodiesel fuels kg CO2 equivalent / GJ of energy supply J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Global warming potential of biodiesel fuels kg CO2 equivalent / GJ of energy supply J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Non-renewable energy demand of biodiesel fuels GJ equivalent / GJ of energy supply J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Biodiesel production J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Water requirement of biofuels Process Litre/MWh corn ethanol irrigation 2,270,000 - 8,670,000 soybean biodiesel irrigation 13,900,000 - 27,900,000 nuclear power plant, open loop cooling 94,600 - 227,100 petroleum extraction + oil refining 90 - 190 Source: Energy Demands on Water Resources; Report to Congress on the Interdependency of Energy and Water; U.S. Department of Energy: Washington, DC, 2006; p 80.
Global electricity generation forecast Source: U.S. Energy Information Administration, 2011
Solar Photovoltaic (PV) Inorganic Solar Cells 2nd Generation Thin-film Bulk 3rd Generation Materials Silicon Germanium Silicon CIS Amorphous Silicon CIGS Mono-crystalline CdTe Poly-crystalline Nonocrystalline Silicon GaAs Ribbon Light absorbing dyes
Solar Photovoltaic (PV) Inorganic Solar Cells Silicon is produced from silica (SiO2) by reacting carbon (charcoal) and silica at very high temperatures. 1.5 tonnes of CO2 is emitted per tonne of silicon (about 98% pure) produced. 2nd Generation Thin-film Bulk 3rd Generation Materials Silicon Germanium Silicon CIS Amorphous Silicon CIGS Mono-crystalline CdTe Poly-crystalline Nonocrystalline Silicon GaAs Ribbon Light absorbing dyes
Solar Photovoltaic (PV) Inorganic Solar Cells 2nd Generation Thin-film Bulk 3rd Generation Materials Silicon Germanium Silicon CIS Amorphous Silicon China’s 2000 MW PV plant will use CdTe (cadmium telluride) . Cd is however toxic. CIGS Mono-crystalline CdTe Poly-crystalline Nonocrystalline Silicon GaAs Ribbon Light absorbing dyes
Solar Photovoltaic (PV) Inorganic Solar Cells 2nd Generation Thin-film Bulk Germanium is an “un-substitutable” industrial mineral. 75% of germanium is used in optical fibre systems, infrared optics, solar electrical applications, and other speciality glass uses. 3rd Generation Materials Silicon Germanium Silicon CIS Amorphous Silicon CIGS Mono-crystalline CdTe Poly-crystalline Nonocrystalline Silicon GaAs Ribbon Light absorbing dyes
Wind turbines 300 kg of Neodymium per 2 GW wind power
Rare earth elements (REEs) Light rare earths (LREEs): Neodymium (wind turbines; smart phones hard disks; headphones; electric & hybrid vehicles; speakers) Lanthanum (lithium-ion batteries) Cerium; Praseodymium; Promethium; Samarium; Europium; Gadolinium
Rare earth elements (REEs) Heavy rare earths (HREEs): Dysprosium(hybrid/electric cars) Terbium (CFL) Holmium Erbium Thulium Ytterbium Lutetium UNOBTAINIUM
Rare earth elements (REEs) Global production of rare earth oxides (in kt) 1950 - 2000
Rare earth elements (REEs) REEs are found as a group and they must be recovered as group and sequentially separated. The lake of toxic waste at Baotou, China, which as been dumped by the rare earth processing plants in the background
The supreme Greek God Zeus told Prometheus: “You may give men such gifts as are suitable, but you must not give them fire for that belongs to the Immortals.” – Roger Lancelyn Green Tales of the Greek Heroes Puffin Classics