Energy Resources
Geothermal Energy: A Free Lunch? Environmental Problems of Geothermal Energy It is Finite Heat Sources Can Be Exhausted (Geysers, California) Sulfur Emissions Disposal of Mineralized Brines Technical Problems of Geothermal Energy Corrosion Mineral Deposition in Pipes Non-Productive gases (Carbon dioxide, methane, etc.) Low Temperatures Low Thermodynamic Efficiency
Thermodynamic Efficiency
Eff. = (Ti - Tf)/Ti T = Degrees Kelvin = Degrees C Ti = initial temperature Tf = final temperature
Thermodynamic Efficiency Automobile Engine Ti = 1200 C = 1473 K Tf = 500 C = 773 K Eff = ( )/1473 = 48% Typical Steam Power Plant Ti = 700 C = 973 K Tf = 200 C = 473 K Eff = ( )/973 = 51%
Thermodynamic Efficiency Geothermal Power Plant Ti = 150 C = 423 K Tf = 80 C = 353 Eff = ( )/423 = 17% Actual achieved efficiencies Automobile on Highway: about 5% Geothermal Plant: 5% or So, Sometimes less than 1%
Nuke-u-lar Energy U-235 fissions to lighter nuclei Naturally 0.7% in uranium ore Must be enriched to 3-4% for reactors Mining is conventional metal mining Radium (decay product) is principal problem in mine wastes
Radiation Hazards Problem in the body is ionization and creation of free radicals Alpha particles (He nuclei) have +2 charge – Do not penetrate skin – Worst ionization problem if ingested Beta particles (Electrons) – Weak penetration ability – Moderate ionization problem Gamma Rays (High Energy photons) – Great Penetrating ability – Lowest ionization ability
Plutonium Produced in small amounts in civilian reactors Toxicity of Plutonium is a Myth – Chemically it is comparable to U, Th – Ra and Rn are worse radiation hazards – Chemical plus Radiation hazard high Main Problem: Long-lived waste product Security issue: Can be Chemically Separated from Uranium
Nuclear Waste Contain until radiation decays to negligible levels (Pu = 24,000 years) Possible Containment Schemes – Yucca Mountain – Crystalline Rock – Salt Domes – Subduction Zones? – Space? Breeder Reactors? – Security Concerns
Fossil Fuels
Coal Seams, Utah
Coal Delta, continental environments – Autochthonous: Grew in Place – Allochthonous: Transported Log Mats Carbonized Woody Material Often fossilized trees, leaves present
Plant Fragments Are Often Visible in Coal
Coal Forms From Wood
Petroleum A hydrocarbon molecule What organisms make these? Answer: None
Petroleum Lots of organisms make these, however Fatty Acids Probable source: Marine plankton
Hydrocarbons C n H 2n+2 NameFormulaMelts CBoils C MethaneCH EthaneC2H6C2H PropaneC3H8C3H ButaneC 4 H PentaneC 5 H HexaneC 6 H OctaneC 8 H DecaneC 10 H EicosaneC 20 H TriacontaneC 30 H
Hydrocarbons Methane = Natural Gas Propane-Butane = Bottled Gas Iso-octane (2,2,4 Trimethylpentane) = Gasoline Cetane (Hexadecane = C 16 H 34 ) = Diesel Fuel Kerosene = Carbons Mineral oil, petroleum jelly, paraffin wax = Carbons Bitumen (Asphalt) ~ 50 Carbons
Iso-Octane (Gasoline)
Abiogenic Petroleum? 18Mg 2 SiO 4 + 6Fe 2 SiO H 2 O + CO 2 → 12Mg 3 Si 2 O 5 (OH) 4 + 4Fe 3 O 4 + CH 4 Olivine + Water → Serpentine + Magnetite + Methane nCH 4 + nFe 3 O 4 + nH 2 O → C 2 H 6 + Fe 2 O 3 + HCO 3 + H + Methane + Magnetite → Ethane + Hematite Minority view in Russia Resurgence among U.S. Right Wing
Petroleum-Bearing Rocks, Utah
Petroleum Traps
Seismic Reflection Profile
Methane Hydrate
Gas Hydrates Hydrocarbons trapped in cage of water molecules Freeze above 0 C under moderate pressure Solid gas hydrates occur in marine sediments (“yellow ice”) Potentially huge energy resource Possible role in climate change?
Energy Use, California, 1972
Energy Use, California, 1979
Energy Use, California, 1993
Energy Use, California, 1994
Energy Use, California, 2003
All You Need to Know
Economics 2000 WINNEBAGO CHIEFTAIN SERIES M-36LP-DSL Average Retail Price: $51,600 Suggested List: $140,851 Source: NADAGuides.com (23 April 2010) Ten-Year Cost: = 297 days = 30 days/year
Planning for the future has long- term benefits Procrastination pays off Now
An Oil Drilling Bit
“World’s Richest Acre”
Offshore Oil Rig
Deep-Water Oil Rig (Houston for Scale)
Anchor Link for Deep Water Rig
Ocean Star, Galveston, Texas
Cutaway of Drill Bit
Soft Rock Bits
Derrick
Pipe Grappler
Drilling Floor
“Christmas Tree”
Well Completion
Rocker
Oil Recovery Primary: Natural Pressure Forces Oil to Surface – Recovery Rate 5 – 15% Secondary: Pumping and Pressurized Fluids – Total After Secondary Recovery: 35-45% Tertiary: Solvents, Steam, Carbon Dioxide – Total After Tertiary Recovery: 50-60% No Underground Resource Recovery Gets All of the Resource
Where Does The Oil Go?
Oil Refinery
Where the Oil Is
The Geography of Oil
Why So Much Oil?
Hubbert Curves In 1956, Oil geologist M. King Hubbert noted that rates of oil production follow a bell-shaped curve. Cumulative production follows a slanting S- curve Production lags discovery by about ten years.
Hubbert’s 1956 Prediction
Where We Stand Today
What if We Find More Oil? Even a huge increase in total oil has very little effect on the peak and decline of production. Why? We waste most of it on inefficient uses.
One Solution: Limit Production
Is There a Lot More Undiscovered Oil? 80 per cent of oil being produced today is from fields discovered before In the 1990's oil discoveries averaged about seven billion barrels of oil a year, only one third of usage. The discovery rate of multi-billion barrel fields has been declining since the 1940's, that of giant (500- million barrel) fields since the 1960's. In 1938, fields with more than 10 million barrels made up 19% of all new discoveries, but by 1948 the proportion had dropped to only 3%.
Oil Discovery Rates
U.S. Petroleum Use ,121,644,500 barrels ,257,125,000 barrels ,384,780,000 barrels ,470,457,000 barrels ,410,770,000 barrels ,175,244,000 barrels ,945,585,000 barrels = 19,498,000 barrels a day = 1 billion barrels in < two months
Global Petroleum Usage 2008 projection: 87 million barrels/day = 31.8 billion barrels per year = 1 billion barrels in 11.5 days = 1000 barrels/second U.S. = 25% of total
Oil Fantasies “America is sitting on top of a super massive 200 billion barrel Oil Field that could potentially make America Energy Independent and until now has largely gone unnoticed. Thanks to new technology the Bakken Formation in North Dakota could boost America’s Oil reserves by an incredible 10 times, giving western economies the trump card against OPEC’s short squeeze on oil supply and making Iranian and Venezuelan threats of disrupted supply irrelevant” (Next Energy News, 13 February 2008)
Realty Check 200 billion 20 million barrels a day = 10,000 days = 27 years Then what? Reality: maybe 10% of the oil is recoverable with known technology The Bakken is a “tight” formation Horizontal drilling can increase yields
Canadian Oil Sands 170 billion recoverable barrels 10 x larger total amount Current production: 1.2 million barrels/day Projected production in 2015 = 3 million barrels per day 3 million barrels = 4 hours of U.S. petroleum consumption
Some Relevant Quotes The internal-combustion engine used for automobiles is a fragile device compared with other prime movers -- even compared with the internal combustion engines used for diesel- electric locomotives that have been known to go over a million miles without mechanical overhauling.
Some Relevant Quotes... the energy-system efficiency of the motor car with petroleum motor fuel is, thus, 5 percent... no one is proud of this accomplishment -- least of all the automotive-design engineers... The trouble is, every time the design engineer manages to save a few BTU it is more than spent answering the clamor for softer tires, for radio, for better heaters, more lights, cigarette lighters and possibly even air conditioning.
Some Relevant Quotes Histories written a few centuries hence may describe the United States as a nation of such extraordinary technologic virility that we succeeded in finding ways of dissipating our natural wealth far more rapidly than any other nation. At any rate, we are having a wonderful time doing it. From the discussions in the earlier chapters of this book it is clear that the problem of energy for the United States is not one of the dim future. It is upon us now.
Some Relevant Quotes Our imports of petroleum are small but each year they become larger. By 1960 they are likely to be quite substantial. By 1970 they will almost certainly be huge -- if foreign oil is still available then in sufficient quantity... This tiny period of earth's life, when we are consuming its stored riches, is nearly over... Fortunately for us there is still time for fundamental research [on alternative energy sources]. But not too much time.
Some Relevant Quotes: Source Eugene Ayres and Charles A Scarlott, 1952; Energy Sources -- The Wealth of the World, McGraw-Hill, 344p.
Petroleum is a Syllogism There is a finite amount of it in the world We are using it and not replacing it Therefore we will eventually run out of it Any of this not clear?
The End of Cheap Oil Known petroleum can last at least a couple of centuries more, but… It only flows through the rocks so fast. No amount of drilling will make it flow faster, and careless drilling can shorten the lifetime of an oil field. Sometime in the 21 st century, global demand will outpace production capacity and… Oil will go to the highest bidder.