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Supplying and Using Energy (VCE Unit 4) Doug MacFarlane School of Chemistry Monash University. www.electromaterials.edu.au. 31 Jan 2002. 5 Mar 2002. 4 Jan 2003. 10 Feb 2003. http://nsidc.org/data/iceshelves_images/. Science (2007). But how Really Serious is all this……. Larsen B.
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Supplying and Using Energy (VCE Unit 4) Doug MacFarlane School of Chemistry Monash University www.electromaterials.edu.au
Science (2007) But how Really Serious is all this…….. Larsen B
Overview Energy and Energy Sources - bio fuels - fuel cells - hydrogen - solar cells - batteries Practical/Project Possibilities Discussion
Program 1 Electromaterials Synthesis and Properties Program 2 Energy Conversion Program 3 Energy Storage Program 4 Bionics
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Bio-carbon fuels
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Bio-carbon fuels Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Bio-carbon fuels Land use, Food supply, Water, Biodiversity Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Geological Carbon fuels (coal, gas, oil) Bio-carbon fuels Land use, Food supply, Water, Biodiversity Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Electricity Generation Automotive Geological Carbon fuels (coal, gas, oil) Bio-carbon fuels Land use, Food supply, Water, Biodiversity Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Electricity Generation Automotive Geological Carbon fuels (coal, gas, oil) Bio-carbon fuels CO2 release to atmosphere Land use, Food supply, Water, Biodiversity Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Hydro, Wind, Tide Electricity Generation Automotive Geological Carbon fuels (coal, gas, oil) Bio-carbon fuels CO2 release to atmosphere Land use, Food supply, Water, Biodiversity Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Hydro, Wind, Tide Electricity Generation Automotive Geological Carbon fuels (coal, gas, oil) Bio-carbon fuels CO2 release to atmosphere Land use, Food supply, Water, Biodiversity Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Hydro, Wind, Tide Land use Electricity Generation Automotive Geological Carbon fuels (coal, gas, oil) Bio-carbon fuels CO2 release to atmosphere Land use, Food supply, Water, Biodiversity Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Hydro, Wind, Tide Land use Electricity Generation Automotive Geological Carbon fuels (coal, gas, oil) Nuclear Bio-carbon fuels CO2 release to atmosphere Land use, Food supply, Water, Biodiversity Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Hydro, Wind, Tide Land use Electricity Generation Automotive Geological Carbon fuels (coal, gas, oil) Nuclear Bio-carbon fuels CO2 release to atmosphere Land use, Food supply, Water, Biodiversity Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Hydro, Wind, Tide Land use Electricity Generation Automotive Geological Carbon fuels (coal, gas, oil) Nuclear Bio-carbon fuels CO2 release to atmosphere Long lived waste Uranium supplies Land use, Food supply, Water, Biodiversity Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Hydro, Wind, Tide Land use Electricity Generation Automotive Geological Carbon fuels (gas, oil) Nuclear Bio-carbon fuels CO2 release to atmosphere Long lived waste Uranium supplies Land use, Food supply, Water, Biodiversity Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Hydro, Wind, Tide Land use Electricity Generation Automotive Geological Carbon fuels (gas, oil) Nuclear Bio-carbon fuels Solar CO2 release to atmosphere Long lived waste Uranium supplies Land use, Food supply, Water, Biodiversity Heating
Energy Sources - Sustainability Unit 4 Area of Study 2 point 1 Source Use Issues Hydro, Wind, Tide Land use Electricity Generation Automotive Geological Carbon fuels (gas, oil) Nuclear Bio-carbon fuels Solar CO2 release to atmosphere Long lived waste Uranium supplies Land use, Food supply, Water, Biodiversity Heating
Brown Coal - The Joy and the Sorrow! • • Victoria has enormous resources • of Brown Coal • • Brown coal has a high water content • => significant quantity of energy used • in evaporating the water • very high CO2 emission • 1kg CO2 per kWh of electricity Coal mining in the La Trobe Valley
Practical: Fermentation and distillation of alcohol BIOCHEMICAL FUELS…..Fuel from plants VCE Unit 3, Area of Study 2 point 6: biochemical fuels including fermentation of sugars to produce ethanol Four main approaches: - fire-wood! - ethanol fermented from sugar/corn syrup - food oils processed into biodiesel - wood pulp processed into petrol
Green Chemistry • Chemicals and chemical processes • ………which are benign by design • Consider all inputs and outputs in a process • Account for whole of life of a chemical • (eg Estrogen pollution) • Develop new approaches • • chemistry in the microwave • • new solvents www.chem.monash.edu.au/green-chem/ www.naturodoc.com/library/hormones/estrogen_pollution.htm
Fermentation and Distillation of Alcohol C6H12O6(aq) 2CH3CH2OH(aq) + 2CO2(g) Yeast Note loss of 2 carbons out 6 Distill CH3CH2OH(l) http://www.csrethanol.com.au/Default.asp Ethanol typically blended with petrol at 10% level
Bio-diesel CH3OH CH3O Ester (biodiesel) • - Bio-diesel typically blended with hydrocarbon diesel as 5 or 10% mix • But: • rain forest clearing in Indonesia for oil crops contributing to Indonesia becoming 3rd largest producer of CO2 • - Nov 2007: UN recommending a moratorium on further development • of biodiesel activity because of impact on food supply • -
Fuel Cells Unit 4 Area of Study 2 point 6 e- Cathode Anode (1/2)O2 + 2e- +2H+ ---> H2O H2 ---> 2H+ + 2e- E0(H+/H2) = 0 V E0(O2/H2O)=1.2V => Ecell ~ 1.2 V H+
The Polymer Electrolyte Fuel Cell NAFION membrane: -(-CF2-CF-)x-(-CF2CF2-)- CF2CF2SO3H http://education.lanl.gov/resources/h2/education.html
The Polymer Electrolyte Fuel Cell Where do we get the hydrogen from? NAFION membrane: -(-CF2-CF-)x-(-CF2CF2-)- CF2CF2SO3H http://education.lanl.gov/resources/h2/education.html
Practical: Electrolysis of water Hydrogen - The Perfect Fuel! 2H2 + O2 = 2H2O • Burns smoothly • No carbon dioxide produced • But: • where do we get it from? • some available from oil wells • …..not enough • possible to make from methane • …. What’s the point!? • Electrolysis of water is best option • …. if we have a source of electricity! • ….or solar electrolysis?
I Solar Water Electrolysis High Potential Energy Electron E(vs SCE) pH = 0 -0.25 +0.95 λ(solar) = 400 - 800nm E(photon) = 3.0 - 1.5 eV e- H+/H2 Band Gap Excitation H2O/O2 h+
Hydrogenation Solar Fuel Solar hydrogen (Water splitting or Thermochemical) Energy content of H2 in a Hydrogen Storage Material = 19 MJ/kg Hydrocarbons Biomass ---> “sugars” Eg glucose eg. gasoline, kerosene Energy content 15 MJ/kg Energy Content = 48 MJ/kg Solar Hydrogen represents > 2/3rds of energy content of the fuel
Chaudhuri et al Nature Biotech 21 (2003) 1229-1233 An Alternative; Microbial Fuel Cells
R. Ferrireducens is a Fe(III) reducing microorganism that exists in anoxic marine sediments Consumes glucose in process C6H12O6 +6H2O + 24Fe(III)----> 6CO2 +24H+ + 24Fe(II) • In the fuel cell it can carry out this reduction with respect to (ie on) the electrode R. Ferrireducens
The Glucose Bio Fuel Cell (1/2)O2 + 2e- +2H+ ---> H2O O2(aq) Carbon electrodes Load Nafion C6H12O6 +6H2O ----> 6CO2 +24H+ + 24e- R. Ferrireducens Glucose(aq) electrons
• Effect of time and replacement of medium • Effect of various electrodes and sugars
Solar Electricity Source NASA: Maximum solar insolation
Photo electrochemical solar cells Efficiency ≈ 10% Load Polymer Electrolyte I3- I - Glass Glass Electrolyte + I- / I3- TiO2 + Ru(bpy)2 Indium/Tin Oxide
Efficiency ≈ 10% Load Polymer Electrolyte I3- I - Glass Electrolyte + I- / I3- TiO2 + Ru dye Tin Oxide
Efficiency ≈ 10% Load Polymer Electrolyte I3- I - Glass Electrolyte + I- / I3- TiO2 + Ru(bpy) Indium/Tin Oxide
Efficiency ≈ 10% Load Polymer Electrolyte I3- I - Glass Electrolyte + I- / I3- TiO2 + Ru(bpy) Indium/Tin Oxide
Efficiency ≈ 10% Load Polymer Electrolyte I3- I - Glass Electrolyte + I- / I3- TiO2 + Ru(bpy) Indium/Tin Oxide
Efficiency ≈ 10% Load Polymer Electrolyte I3- I - Glass Electrolyte + I- / I3- TiO2 + Ru(bpy) Indium/Tin Oxide
Efficiency ≈ 10% Load Polymer Electrolyte I3- I - Glass Electrolyte + I- / I3- TiO2 + Ru(bpy) Indium/Tin Oxide
Efficiency ≈ 10% Load Polymer Electrolyte I3- I - Glass Electrolyte + I- / I3- TiO2 + Ru(bpy) Indium/Tin Oxide
Efficiency ≈ 10% Load Polymer Electrolyte I3- I - Glass Electrolyte + I- / I3- TiO2 + Ru(bpy) Indium/Tin Oxide