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Energy Options in a Carbon Constrained World. Martin Sevior, School of Physics, University of Melbourne. Energy underpins our Civilization. Imagine one week without Electricity. Imagine one week without Motorized transportation.
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Energy Options in a Carbon Constrained World. Martin Sevior, School of Physics, University of Melbourne http://nuclearinfo.net
Energy underpins our Civilization Imagine one week without Electricity Imagine one week without Motorized transportation We rely heavily on Fossil Fuels to provide the energy our civilization needs. However our finite Earth constrains our future use of these. http://nuclearinfo.net
Energy use without constraints Non-OECD Countries are growing very quickly and are consuming an ever-increasing amount of energy. http://nuclearinfo.net
Is Oil coming up against a wall? • Australia’s Oil production peaked in 2000 • Will/When will World Oil production peak? (http://sydneypeakoil.com/phpBB/viewtopic.php?t=1972) http://nuclearinfo.net
Energy Data from 2005 Burning Fossil Fuels produces CO2 http://nuclearinfo.net
CO2 increase in the Atmosphere http://nuclearinfo.net
Total World CO2 emissions • Total world demand for energy is expected to at least double by 2050 • Much is this growth is in the third world which needs energy to escape poverty “If we have to free our people from drudgery and ill-health, we need to address the issue of access to energy, particularly the need for rural masses” Manmohan Singh, Prime Minister of India on plans to expand electricity generation capacity from 110 GW to 980 GW by 2030. (Australia has 40 GW of electricity generation.) http://nuclearinfo.net
Greenhouse Emission targets • Kyoto protocol • Reduce Greenhouse emissions by 5.2% from 1990 levels by 2008-2012 • This is extremely hard. eg Canada has increased it’s emissions by 20% since 1990 • Future • Reduce greenhouse emissions by 60% from 1990 levels by 2050 to stabilize temperature rise to 2 C http://nuclearinfo.net
Scale of the challenge What is wanted Possible Needed Conventional Oil and Natural Gas cannot keep pace with demand nor should they. http://nuclearinfo.net
Default for Electricity is Coal Additional CO2 emissions due to new Coal Fired Power Stations to 2020 http://nuclearinfo.net
Australia’s Challenges Conventional Oil production is declining, we rely on imports Our CO2 emissions are the largest per Capita in the OECD http://nuclearinfo.net
Australian CO2 emissions Around 50% of Australia’s CO2 emissions are from electricity production. http://nuclearinfo.net
Options for Transport Convert Coal to Oil (Monash Energy Project, being developed) Convert Gas to Oil (under active Consideration) Use LPG (well underway) or Natural Gas (not persued) Rework our Cities, Public transport improvements BioFuels – Ethanol, BioDiesel (May meet 10% of current demand) More Efficient Vehicles http://nuclearinfo.net
Transport can be far more efficient Gasoline Engines are on-average 10% efficient Modern Diesel Engines are 20% efficient Fuel cells vehicles can reach 50% efficiencies Batteries/Electric engines are 80% efficient The electric route means same transport with 1/8th the energy. http://nuclearinfo.net
Next generation batteries 0 – 100 km/hr in 4 seconds, 400 km range, available 2007 Cost US $100K For the rest of us, Plugin Hybrids, (60 km range on electric) are likely to enable us to continue to use personal transportation post 2010 If sourced from electricity with low carbon emission technologies can substantially reduce world CO2 emissions http://nuclearinfo.net
Electricity Generation Our current coal-fired power stations provides us with cheap and reliable electricity. Electricity costs vary depending on the coal quality and distance from mines. Queensland Black Coal generates electricity at less than 3 cents per KW-Hr. Victoria generates electricity at 4 cents KW-Hr But if we’re to meet our target of 60% CO2 emissions, we must close many of them or at least not use them as much. What can we do for Electricity? http://nuclearinfo.net
Energy Efficiency Over the past 5 years, Australia’s electricity consumption has grown by 3.7% per year. To some extent this reflects our very cheap electricity. This are a variety of energy efficiency gains available throughout the economy. All require investment of time and money. Achieving additional efficiency gains in addition to those made via “natural” processes, almost certainly requires higher prices. http://nuclearinfo.net
Natural Gas Natural Gas produces half the CO2 for the same amount of electricity. Output can be altered quickly so it can be usefully paired with renewable energy sources such as wind and solar. However, Natural Gas is also a finite resource and it’s world-wide production rate is likely to peak within the the next 20 years. Gas produced electricity, at current international prices of $6 per GigaJoule, costs around 7 cents/KW-Hr http://nuclearinfo.net
Wind Power Wind is the leading renewable energy source. Cost is 7 – 9 cents/KW-Hr but is unlikely to decrease. Intermittency and variability of output mean diminishing returns after 10% – 20% of total capacity. http://nuclearinfo.net
The problem with variability In order to make a difference in CO2 outputs, you have to actually turn off (or down) coal-fired generators. Victoria’s goal of 10% Renewable by 2015 if met by wind requires about 2 GW of peak output Output from wind can vary by 90% over 1 hour Baseload generators require 6 hours to ramp through 80% of their output. At higher percentages the problem gets worse, 30% wind in Victoria requires 6 GW of peak output. http://nuclearinfo.net
Solar Energy Fundamentally factor of 20 higher flux than wind. Commercial PV systems currently provide electricity at 25-50 cents per KiloWatt-Hour Solar works at small scale, so can compete at the retail level of 10 –14 cents/KW-Hr Huge potential for improvements (factor 4 – 10 decrease in price). eg Sliver Cells (developed at ANU), Nanosolar (California) rolls of thin film CIGS (400 MW factory), SolarSystems (Vic.) concentrators The Nanosolar factory is costed at $100 million and expects to produce product worth $2 billion / year. Variability and intermittency issues remain after costs are reduced – needs storage. http://nuclearinfo.net
Carbon Capture and Storage Coal is gasified into CO and H2 streams. If combusted in pure O2, a pure CO2 stream emerges. This can be reinjected into underground reservoirs. Intensely challenging – cubic kilometers of CO2 per year! The coal gasification process depends on the properties of the coal (moisture content, sulphur and other impurities). The CO2 storage procedure depends on the properties of the local site. All need detailed modeling Appears feasible in Victoria’s Latrobe Valley but more study is needed. Late 2010’s – 2020. Electricity cost is expected to increase by 1 – 4 cents/Kw-Hr http://nuclearinfo.net
Nuclear Power A “drop in” replacement for coal-fired base-load generation. When used at world-best practice, emits about 1% of the greenhouse gases of fossil-fuel plants. Fuel is abundant and will last for centuries. New plants expected to produce electricity in the range 4-7 cents KW-Hr Need considerable operating and regulatory expertise which does not yet exist in Australia Needs additional infrastructure for Waste Disposal Fierce Opposition from some in the community. http://nuclearinfo.net
Others Hydro – almost fully exploited already in Australia GeoThermal – Immature and of limited availability BioMass: Useful for small scale local developments to utilize waste. (eg Saw Dust and Bagasse) Large scale usage faces significant environmental challenges and transport issues. http://nuclearinfo.net
Leading technologies http://nuclearinfo.net
Concluding remarks Without storage, intermittency and variability of wind and solar likely to limit penetration to 30%. Solar energy is worth direct Government support. Achieving 60% reduction in CO2 emissions while growing electricity consumption requires replacing our existing Coal fired power stations with Nuclear or Carbon Capture. Nuclear Power has proven track record of delivering large amounts of reliable electricity. All options are more expensive than current coal. http://nuclearinfo.net
Backup Slides http://nuclearinfo.net
Myths about Nuclear Power 1. We’ll soon run out of Uranium We’ve mined less than one ten millionth of the Uranium in the Earth’s crust. If we need to use lower grade ore’s there is hundreds to thousands of times more we can extract. 2. It takes seven years to recover the energy consumed constructing the plant. Nuclear Power plants use approximately one quarter the concrete and steel of a an equivalent amount of wind turbines. Modern studies show Nuclear Power repays it’s energy cost in a few months http://nuclearinfo.net
3. Mining Uranium uses a huge amount of energy and produces larges amounts of Greenhouse gases The lowest grade large mine currently operating, Rossing in Namibia, requires just 1 PJ of energy to produce Uranium that generates over 400 PJ of electricity. 4. Nuclear Power Plants are dangerous and will blow up like Chernobyl The Western Nuclear Power Industry has an extremely good safety record an order of magnitude better than the Fossil Fuel industry Chernobyl had a number of obvious design flaws and was operated in a environment of no safety culture http://nuclearinfo.net
5. Terrorists will blow up Nuclear Power Plants The concrete and steel containment shell that surrounds a nuclear power plants is extremely strong. Simulations predict a it will survive the impact of a fully laden passenger jet. Spent fuel assemblies can be stored underground Nuclear Power is a “Hard” target. 6. Takes too long In the time it takes Victoria to build up to 10% renewable energy, twice the amount of Nuclear Power could be built for the same capital cost. Unlike Wind or Solar, Nuclear could scale to replace all our coal plants. http://nuclearinfo.net
http://nuclearinfo.net • Alaster Meehan • Gareth Jones • Damien George • Adrian Flitney • Greg Filewood Technical Support • Ivona Okuniewicz • Lyle Winton Reviewed by: • Dr. Andrew Martin Web Design • University of Melbourne Writing Center http://nuclearinfo.net
Energy and Entropy • 2nd Law of Thermodynamics • Entropy tends to increase • Sharing of energy amongst all possible states • Life is in a very low state of entropy • To exist it must create large amounts of entropy elsewhere. (S = Q/T) • Life requires large amounts of Energy. http://nuclearinfo.net
Life and energy • Life takes energy from the sun Life represents a ~0.02% decrease in entropy from the sun heating earth http://nuclearinfo.net
Energy and civilization • Our Civilization is based on cheap energy and machines • Previous civilizations utilized humans and animals. (Still the case for large parts of the world.) • Given sufficient quantities of energy our civilization can generate all the products it needs. (Food, Health, Metals, Plastics, Water) http://nuclearinfo.net
Energy in Australia • Australia’s Electricity needs are currently supplied by 40 GigaWatts of power stations. • Our electricity demand is forecast to grow by over 2% per year to 2020 • On average 1.0 GigaWatts increase each year • Equivalent to Loy-Yang B Power Station http://nuclearinfo.net
World Energy Growth. Energy Growth by “region” Energy Growth by source Projections are “business as usual” Source: U.S. Energy Information Administration. http://nuclearinfo.net
Growth in a finite system Q =P/T P = Amount Produced T= Total available http://nuclearinfo.net
Growth in a finite system C(t) = T Q P(t) = TdQ\dt http://nuclearinfo.net
Global Temperature Measurements http://nuclearinfo.net
Myths about Climate Change • Myth- Water vapour is the main source of Greenhouse heating so CO2 makes no difference. • Residency time of water is 10 days, CO2 is ~100 years. CO2 is the driver, water vapour provides feedback/amplification. • Myth - CO2 absorption lines are saturated. • Only true at ground level. The upper atmosphere is sensitive to CO2 concentration • Net effect of doubling CO2 is an additional 4 watts/m2 extra heat. • No climate model shows a decrease in temperature with an increase in CO2 http://nuclearinfo.net
The transition. • Having access to large amounts of cheap energy is vital for our civilization. • Over the next human generation we will need to manage a transition from our Fossil-Fuel based energy sources • The combination of resource depletion and Climate Change mitigation forces this. • Getting this right is vital for the world we leave our children. • I believe that this is one of the great issues facing this generation. http://nuclearinfo.net
Nuclear Energy • About 6 Billion years ago a supernova exploded in this region of space. • About 1 solar mass of hydrogen was converted to Helium in about 1 second • All the elements heavier than Lithium were created making life possible in the solar system • A tiny fraction of the energy was used to create heavy elements like Uranium and Thorium. http://nuclearinfo.net
Nuclear Energy • Chemical reactions release a few electron-volts of energy per reaction. Nuclear Fission releases 200 Million electron volts per reaction A neutron is captured by 233U,235U or 239Pu. The nucleus breaks apart and releases 2-3 more neutrons. These in turn can induce further fissions. http://nuclearinfo.net
Nuclear energy • The energy release from a single fission reaction is about one-tenth that of an anti-matter annihilation. • There is as much energy in one gram of Uranium as 3 tonnes of coal. • The reaction produces no CO2 • So how much Uranium is present on Earth? http://nuclearinfo.net
Uranium Abundance. • The Earth’s crust is estimated to contain 40 trillion tonnes of Uranium and 3 times as much Thorium. • We have mined less than a ten millionth of this. (We have extracted about half of all conventional Oil) • If burnt in a “4th Generation” reactor provides 6 Billion years of energy. • If burned in a current reactor enough for 24 Million years. • But most is inaccessible. How much is really available? • Look at Energy cost of mining compared to energy Generated in Reactors http://nuclearinfo.net
Uranium Abundance Proven reserves as of June 2006 amount to 4.7 Million tonnes, sufficient for 85 years at present consumption rates Rossing mine in Namibia has a Uranium abundance of 350 ppm and provides an energy gain of 500 Extrapolating to 10 ppm provides an energy gain of 14 4th Generation reactor (50 times more efficient Uranium usage) provides an energy gain of 100 at 2 ppm At least 8,000 times more Uranium can be usefully mined using current reactors. 32,000 times more with 4th Generation. (96 million years worth.) http://nuclearinfo.net
Uranium in Sea Water • Very low concentration 3 mg/m^3, but a huge resource ~ 4.5x109 tonnes • Japanese experiment recovered > 1 Kg in 240 day exposure http://nuclearinfo.net
Nuclear Power • Nuclear Power has been demonstrated to work at large scale. • France (80% Nuke, 20% Hydro) and Sweden (50% Nuke, 50% Hydro) have the lowest per capita greenhouse emissions of large countries in the OECD • Australia, with it’s reliance on Coal-powered electricity, has the highest http://nuclearinfo.net
Nuclear Greenhouse Gas emissions The Nuclear Fuel cycle is complex. How much Greenhouse Gases are produced? http://nuclearinfo.net