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Energy in the 21st Century. Presentation for University of Chicago Physics Colloquium April 3, 2008 Burton Richter Freeman Spogli Institute of International Studies Senior Fellow Paul Pigott Professor in the Physical Sciences Emeritus Stanford University and Former Director
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Energy in the 21st Century Presentation for University of Chicago Physics Colloquium April 3, 2008 Burton Richter Freeman Spogli Institute of International Studies Senior Fellow Paul Pigott Professor in the Physical Sciences Emeritus Stanford University and Former Director Stanford Linear Accelerator Center
10.000 5,000 0 Years before 2,005
Average Temperature of the Earth • Turn off Greenhouse Effect • All energy radiated from surface escapes. • Average T = -4°F (-20°C). • Turn on Greenhouse Effect • Part of energy radiated is blocked. • Surface T goes up so what gets through balances incoming. • Average T = 64°F (15°C).
°C Green bars show 95% confidence intervals 2005 was the hottest year on record; the 13 hottest all occurred since 1990, 23 out of the 24 hottest since 1980. J. Hansen et al., PNAS 103: 14288-293 (26 Sept 2006)
IIASA Projection of Future Energy Demand Scenario A1 (High Growth)
Projected Global Average Surface Warming at the End of the 21st Century Source IPCC 4AR WG1
Reference Scenario: World Primary Energy Demand 18 000 Other renewables Nuclear 16 000 Biomass 14 000 Gas 12 000 10 000 Mtoe Coal 8 000 6 000 4 000 Oil 2 000 0 1970 1980 1990 2000 2010 2020 2030 From International Energy Agency “World Energy Outlook 2006” Global demand grows by more than half over the next quarter of a century, with coal use rising most in absolute terms
Total Primary Energy Supply by Fuel (Source: IEA “Key World Energy Statistics 2007”)
CO2 emissions paths: BAU versus stabilizing CO2 concentration to limit ∆Tavg BAU ( 6°C+) (~3°C) (~2°C) Path for 50% chance of avoiding ∆Tavg >2°C (gold) is much more demanding than path for 50% chance of avoiding >3°C (green).
Primary Power Requirements for 2050 for Scenarios Stabilizing CO2at 450 ppm and 550 ppm M. Hoffert, et al., Nature, 395, p881, (Oct 20, 1998)
CARBON-FREE ENERGY Ready for Large-Scale Deployment Now Conservation and Efficiency. Nuclear for Baseload Application. Ready for Limited Deployment Now Solar for Daytime Use. Wind with Back up from Others.
Power (TW) Required in 2050 Versus Rate of Decline in Energy Intensity
(Fossil Fuel Combustion Only) 25.00 United States 20.00 Netherlands Australia Canada 15.00 Belgium Tons of CO2 per person California Denmark Germany 10.00 Austria Japan New S. Korea Zealand Italy Switzerland France 5.00 Mexico 0.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 intensity (tons of CO2 per 2000 US Dollar) Carbon Dioxide Intensity andPer Capita CO2 Emissions -- 2001
Peak Load vs. Base Load Peak Load Base Load
Solar comes in 3 Varieties • Solar Hot Water – simple, cheap, old fashioned, effective • Solar Photovoltaic – spreading, expensive, particularly good for small & distributed • Solar Thermal Electric – large scale, beginning to be deployed more widely
Solar Photovoltaic • Expensive but costs are coming down. • Also has a storage problem (day-night, clouds, etc.). • Some places solar can be important. • In U.S. solar is negligible (less than 10% of wind, mostly in CA).
Solar Thermal Electric • Barstow Solar 2 Power Tower (photo courtesy of NREL)
Wind • Commercially viable now (with 1.9¢/kw-hr subsidy). • Nationally about 11,000 Megawatts of installed capacity (2500 in CA). • But, the wind does not blow all the time and average energy delivered is about 20% of capacity. • Wind cannot be “baseload” power until an energy storage mechanism is found.
100-Mile Circle Altamont Pass Wind Farm
EON-NETZ (GERMANY) WIND POWER VARIABILITY AVERAGE IS 20% OF INSTALLED WIND CAPACITY
Other Renewables • Big Hydroelectric: About 50% developed world wide. • Geothermal: California, Philippines, and New Zealand are the largest (CA ≈ 1.5 Gigawatts). • Bio Fuel: A very complicated story, and verdict not yet in.
Coal Largest Fossil Fuel Resource. US & China each have about 25% of world resources. IF CO2 emitted can be captured and safely stored underground, problem of reducing Greenhouse Gas emissions is much easier.
CO2 Sequestration • Most study has been on CO2 injection into underground reservoirs. • Capacity not well known.
FutureGen $1 Billion Industry-Government Partnership to Generate Electricity & Sequester the CO2.
The Nuclear Critics • It can’t compete in the market place. • It is too dangerous. • We don’t know what to do with spent fuel. • Proliferation risk is too big to accept.
Nuclear Accidents Chernobyl (1986) – World’s Worst Reactor type not used outside of old Soviet bloc(can become unstable) Operators moved into unstable region and disabled all safety systems. Three Mile Island (1979) – A Partial Core Meltdown LWRs are not vulnerable to instabilities All LWRs have containment building Radiation in region near TMI about 10 mr. New LWRs have even more safety systems.
Internationalize the Fuel Cycle Supplier States: Enrich Uranium Take back spent fuel Reprocess to separate Actinides Burn Actinides in “Fast Spectrum” reactors User States: Pay for reactors Pay for enriched fuel Pay for treatment of spent fuel (?)
Conclusion • Global Warming is real and human activity is the driver. • Not clear how bad it will be with no action, but I have told my kids to move to Canada. • We can do something to limit the effects. • The sooner we start the easier it will be.
Conclusion • Best incentives for action are those that allow industry to make more money by doing the right thing. • Carrots and sticks in combination are required. • The economy as a whole will benefit, but some powerful interests will not. • It is not hard to know what to do, but very hard to get it done.
The Most Difficult World Problem • What should be the criteria for action? • Total emissions? • Per capita emissions? • Greenhouse gas per unit GDP? • The poorest countries contribute negligibly – Leave them out. • The rapidly developing countries have to be brought in somehow. • The rich countries have to lead the action agenda.
Comparison of Life-Cycle Emissions Source: "Life-Cycle Assessment of Electricity Generation Systems and Applications for Climate Change Policy Analysis," Paul J. Meier, University of Wisconsin-Madison, August, 2002.
Some Comparative Electricity Generating Cost Projections for Year 2010 on US 2003 cents/kWh, Discount rate 5%, 40 year lifetime, 85% load factor.Source: OECD/IEA NEA 2005.
Public Health Impacts per TWh* *Krewitt et al., “Risk Analysis” Vol. 18, No. 4 (1998).