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L’énergie et la soutenabilité Dr. Julia K. Steinberger

L’énergie et la soutenabilité Dr. Julia K. Steinberger. Cours: Les enjeux scientifiques et institutionnels de la soutenabilité Jacques Grinevald, Rolf Steppacher, Marlyne Sahakian Semestre de printemps 2009 IHEID. Programme.

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L’énergie et la soutenabilité Dr. Julia K. Steinberger

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  1. L’énergie et la soutenabilitéDr. Julia K. Steinberger Cours: Les enjeux scientifiques et institutionnels de la soutenabilité Jacques Grinevald, Rolf Steppacher, Marlyne Sahakian Semestre de printemps 2009 IHEID

  2. Programme • Qu’est-ce que l’énergie? Comment l’utilisons-nous? Quels enjeux pour la soutenabilité? • Concepts de base, sources et vecteurs énergétiques, échanges internationaux, réchauffement climatique -------------------PAUSE--------------- • Enjeux importants de l’énergie • Energie et économie • Energie et croissance, effet rebond, études de consommation • Economie de la performance/fonctionalité • Energie et développement humain • Conclusions, questions, discussion Julia K. Steinberger | IHEID | 17.04.2008 | 2 / 92

  3. Basic concepts How do you define energy? Julia K. Steinberger | IHEID | 17.04.2008 | 3 / 92

  4. Energy: definition related to physical forces • Definition of energy: in physics, energy is the work that a force can or could do. • Forces are: • gravitational (due to interaction between mass and energy concentrations) • electric (attraction and repulsion of charged particles) • magnetic (attraction and repulsion of magnetic objects) • chemical (driving chemical reactions: electro-magnetic) • nuclear (binding nuclei together or breaking unstable apart) • mechanic (impact of one moving object on another) Julia K. Steinberger | IHEID | 17.04.2008 | 4 / 92

  5. Forms of energy • Energy can take many forms • kinetic (movement of a mass) • electric, magnetic (movement of charges or electromagnetic fields radiating) • Electricity • Radiation (light) • chemical (molecules with internal energy) • heat (thermal) (statistical expression of kinetic energy of many objects in a gas, liquid or solid - or even radiation) • potential (water above a dam, a charge in an electric potential or a battery) Other examples? Julia K. Steinberger | IHEID | 17.04.2008 | 5 / 92

  6. SI units for energy • The SI unit of energy is a Joule: 1 kg*m2/s2 = 1 Newton*m (Newton is the unit of Force) • mass * velocity 2 • mass * g * height (on earth, g = 9.81 m/s2 ) • for an ideal gas = cvkBT (cv =3/2 for a monatomic gas) • Power is energy per time: 1 Watt = 1 Joule/s = 1 kg*m2/s3 • most commonly used in electricity, but also for vehicles in horsepower (acceleration time) Julia K. Steinberger | IHEID | 17.04.2008 | 6 / 92

  7. Other common energy units http://www.onlineconversion.com/energy.htm Julia K. Steinberger | IHEID | 17.04.2008 | 7 / 92

  8. What is energy for? Examples of: • Kinetic • Electro-magnetic • Electricity • Radiation (light) • Chemical • Potential • Heat (thermal) ? How do you use energy? Julia K. Steinberger | IHEID | 17.04.2008 | 8 / 92

  9. Practical energy: what is it for? Energy in daily life: we use it to ... • stay alive (food, oxygen: chemical) • move faster (transportation fuel: chemical) • keep warm (heating fuel: chemical) • almost everything else (keep cold, preserve food, light and ventilate spaces, cook, run machines, communicate, measure, store data, compute,...): electricity In industrial processes: we use it to … • Extract (mechanical), refine (chemical), synthesize (chemical), shape (heat, mechanical), assemble (mechanical): produce Julia K. Steinberger | IHEID | 17.04.2008 | 9 / 92

  10. Energy conversion • Energy conversion: from one type to another • Examples: • Chemical to kinetic • Chemical to electric • Potential to electric • Thermal to electric • Chemical to thermal • Radiation to chemical • Radiation to electric • Radiation to thermal • Electric to thermal • Electric to chemical Julia K. Steinberger | IHEID | 17.04.2008 | 10 / 92

  11. Why is this important? Efficiency • What is efficiency? • Output / Input • Energy out / energy in for an energy conversion process? • Energy out = energy in , so not very useful • Useful energy out / energy in • Physical work / Heat content of fuel • Electricity / physical work • Food / Inputs to agriculture Julia K. Steinberger | IHEID | 17.04.2008 | 11 / 92

  12. Julia K. Steinberger | IHEID | 17.04.2008 | 12 / 92

  13. Efficiencies (2) Source: Smil 1999

  14. t r t c e e r Chain of conversion efficiencies:Light bulb Source: Tester et al 2005 Etotal = E1 x E2 x E3 = 35% x 90% x 5% = 1.6% Julia K. Steinberger | IHEID | 17.04.2008 | 14 / 92

  15. Example 5: walking-running-biking kcal/mile

  16. Conservation, but … • Energy is ALWAYS conserved • However, energy is not always useful: dissipated heat is usually not recoverable. • Useful energy is an anthropocentric concept in physics: from study of thermodynamics • Thermodynamics investigates statistical phenomena (many particles, Avogadro’s number = 6×1023): energy conversion involving heat. Julia K. Steinberger | IHEID | 17.04.2008 | 16 / 92

  17. 3+1 laws of thermodynamics • If systems A and B are in thermal equilibrium with system C, A and B are in thermal equilibrium with each other (definition of temperature). • Energy is always conserved. • The entropy of an isolated system not at equilibrium will tend to increase over time. • As temperature approaches absolute zero, the entropy of a system approaches a constant. Julia K. Steinberger | IHEID | 17.04.2008 | 17 / 92

  18. Paraphrases of 2 laws of thermodynamics • You can’t get something from nothing. • You can’t get something from something. • You can't get anything without working for it. The most you can accomplish is to break even. • You even can't break even. • (economics) There is no such thing as a free lunch. Julia K. Steinberger | IHEID | 17.04.2008 | 18 / 92

  19. History of thermodynamics (2nd law) Nicolas Léonard Sadi Carnot (1796-1832) • Theory of heat engines, “reversible”Carnot cycle: 2nd law of thermodynamics Ludwig Boltzmann (1844-1906) • Kinetic theory of gases (atomic) • Mathematical expression of entropyas a function of probability

  20. Comparison of heat engines h = 1 - TC/ TH

  21. Types of power (electricity) generation • Heat engines: Based on heat (fossil combustibles or nuclear) • Others • Hydraulic power: gravitational energy of water • Wind power: kinetic energy of air • Solar power: radiation from sun • Tidal power: kinetic energy of tides or waves Julia K. Steinberger | IHEID | 17.04.2008 | 21 / 92

  22. Implications of entropy for economics • Geogescu-Roegen (1906-1994), Romanian economist, wrote The Entropy Law and the Economic Process in 1971. • Points out that economic processes are not circular, but take low entropy (high quality resources) as inputs and produce high entropy emissions (degraded wastes). • Worries about CO2 emissions from fossil fuel burning • Concludes that current entropy production is too high, advocates solar input scale for global economy. Julia K. Steinberger | IHEID | 17.04.2008 | 22 / 92

  23. Environment Society Economy Georgescu-Roegen (2) « Le processus économique n’est qu’une extension de l’évolution biologique et, par conséquent, les problèmes les plus importants de l’économie doivent être envisagés sous cet angle » Vision G-R, reprise par H. Daly et l'économie écologique Vision Brundtland 1987 du développement durable Environment Economy Society

  24. Georgescu-Roegen (3) " Chaque fois que nous produisons une voiture, nous détruisons irrévocablement une quantité de basse entropie qui autrement, pourrait être utilisée pour fabriquer une charrue ou une bêche. Autrement dit, chaque fois que nous produisons une voiture, nous le faisons au prix d'une baisse du nombre de vies à venir." concepts clefs: le patrimoine limité de l'humanité en ressources naturelles et donc la responsabilité envers les générations suivantes The entropy law and the economic process Julia K. Steinberger | IHEID | 17.04.2008 | 24 / 92

  25. Basic concepts (cont.) Origin of energy How do we get energy? Where does it all come from? (not so simple...) Energy system (primary, final, useful, energy services) Julia K. Steinberger | IHEID | 17.04.2008 | 25 / 92

  26. Origin of energy on earth • Food? Solar (via photosynthesis) • Oxygen? Solar (via photosynthesis) • Wood for burning? Solar (via photosynthesis) • Fossil fuels? Solar (via photosynthesis and geological processes: geothermal heating, pressure) • Hydraulic or wind? Combination of solar and earth's rotation (Coriolis effect) • Tidal power? Gravitational energy of moon and earth’s rotation • Geothermal? Combination of nuclear fission and gravitation. • Nuclear fission? Astrophysical supernova explosion energy. How do we compare such different sources? Julia K. Steinberger | IHEID | 17.04.2008 | 26 / 92

  27. Energy chain

  28. Lifestyle Energy system: services Julia K. Steinberger | IHEID | 17.04.2008 | 28 / 92

  29. Energy carriers

  30. Why does energy matter? • Not everyone has enough energy (ACCESS) • Some energy supplies are uncertain (SECURITY) • Some energy sources are in finite global supply (SCARCITY) • Energy sources are not equally geographically distributed (DISTRIBUTION) • Some energy sources are intermittent (STORAGE) • Local nvironmental impacts from energy use (POLLUTION) • Environmental impacts from energy use are changing the earth's climate (GLOBAL CATASTROPHE) Julia K. Steinberger | IHEID | 17.04.2008 | 30 / 92

  31. Energy carriers in our daily lives • Biomass (food, fuel, fertilizer) • Fossil fuels: oil (liquid), coal (solid), natural gas • Heat (solar, geothermal) • Electricity: through electric grid • Electricity: through battery or fuel cell (chemical energy) Julia K. Steinberger | IHEID | 17.04.2008 | 31 / 92

  32. Uses for specific carriers • What can you use for heat? Solar radiation, geothermal, burn biomass or any fossil fuel, dissipate electricity in a resistance => EVERYTHING What can you use for transportation? Yourself (biomass), animals (biomass), oil (cars,buses, trains, planes), compressed or liquid natural gas (cars, buses, trains), coal (trains), electricity (grid transportation: bus, tram, train), electric unit (battery or fuel cell) => almost everything. Then why is oil the best transportation fuel ever? What can you use for light? Electricity, oil, gas, biomass What can you use for appliances? ELECTRICITY Julia K. Steinberger | IHEID | 17.04.2008 | 32 / 92

  33. Global energy used for transport (Exajoules) Data: IEA Julia K. Steinberger | IHEID | 17.04.2008 | 33 / 92

  34. Important properties of energy carriers • Abundance • Availability • Cost (economic) • Rate of supply (renewable vs. fossil) • Energy density (MJ/kg) • Time-dependence of supply • Storage • Distribution • Production: centralized or distributed • Environmental impacts (risk, pollution) Julia K. Steinberger | IHEID | 17.04.2008 | 34 / 92

  35. Energy densities • What do you estimate the density of different energy carriers to be? • For food: need ~ 2500 kcal/day • 1000 kcal ~ 4 MJ • so ~ 10 MJ per day. • How many kg of rice or pasta (carbohydrates) or cookies (carbohydrates + fat) do you need to eat per day? • 0.75 kg or rice or pasta: 15 MJ/kg or 360 kcal/100g • 0.5 kg of cookies: 20 MJ/kg or 500 kcal/100g Julia K. Steinberger | IHEID | 17.04.2008 | 35 / 92

  36. Energy densities of selected carriers • Food: fat = 39.2 MJ/kg protein = carbohydrates = 17.2 MJ/kg (reason why food labels are in weight, not calories) • Biomass: 10 MJ/kg (green wood) => 20 MJ/kg (sugar cane bagasse, cotton hulls, oven-dried wood) • Coal: 17 MJ/kg (lignite) => 31.4 MJ/kg (anthracite) • Oil: 42 MJ/kg (crude) => 46 MJ/kg (kerosene) • Methane: 55.5 MJ/kg • Hydrogen: 142 MJ/kg • Uranium in light water reactor: 443'000 - 3'456'000 (enriched 3.5%) MJ/kg Julia K. Steinberger | IHEID | 17.04.2008 | 36 / 92

  37. food biomass

  38. food biomass

  39. 2000 Watt society Sources: USA Energy Information Agency Annual Energy Review 2005 , USA Census Measuring America (2002)

  40. Comparison of per capita DEC in the UK and Austria 1830-2000 Source: Krausmann 2007 Includes food biomass

  41. OIL Julia K. Steinberger | IHEID | 17.04.2008 | 41 / 92

  42. Abundance, access, distribution: OIL Source: BP Statistical Review of World Energy 2006

  43. World-wide oil trade Source: BP Statistical Review of World Energy 2004

  44. Zittel, Schindler et al 2004: (non-OPEC countries) Peak Oil? Prediction of Marion King Hubbert, 1956 Hubbert's peak Julia K. Steinberger | IHEID | 17.04.2008 | 44 / 92

  45. Or no peak oil? Note: better extraction/prospection, inflation of reported reserves to avoideconomic loss of confidence? Source: BP Statistical Review of World Energy 2006

  46. Any reasons for fluctuations? Source http://www.wtrg.com/prices.htm

  47. This week More recent prices: light crude futures Source: 2008 http://futures.tradingcharts.com/ Julia K. Steinberger | IHEID | 17.04.2008 | 47 / 92

  48. Metrics for transportation • Personal transportation: passenger*kilometre • Freight transportation: tonne*kilometre Source OECD 1996

  49. Denver LA Toronto NYC Bangkok Geneva Barcelona Prague Cape Town London CO2 emissions from transportation in 10 cities Julia K. Steinberger | IHEID | 17.04.2008 | 50 / 92 Kennedy, Steinberger et al 2009

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