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Chapter 16

Energy Resources

Dr. Joao Santos

Chapter 16

Energy Resources

Dr. Joao Santos

Introduction

• Fundamental lifeblood for industrialization

• Disproportionate amount of energy resources demanded and consumed in developed countries

• Growing challenges: How to break energy dependency, yet sustain development and high standard of living

• Energy shocks: Constant worries from past to present and to the future over the price, dependency, power failure

Case History: Energy Transition 1800–

• The amount of fossil fuels in the Earth is finite

• Energy transformation in the United States from wood in

the mid-1800s to fossil fuels in the mid-1900s, the peak in

use of wood was approximately 1870

• It took something like 100 years for the full transition

• Shortages of wood in 1812 in Philadelphia led to

experiments of burning coal, and the first oil well was

completed in 1858

• Peak oil production (when about one-half of Earth’s

recoverable oil will have been produced and used) is

likely to occur sometime between 2020 and 2050

• Another transition is in the making, from oil to alternative

energy sources

Case History: Energy Transition 1800–

Energy Shocks Past and Present

• 2000 years ago, affluent Roman citizens had central heating that consumed vast amounts of wood— perhaps as much as 125 kg (275 lb) every hour

• To combat the shortages, the Romans had to import wood from distances as far away as 1600 km (995 mi)

• They turned to solar energy as an alternative

• During the summer of 2008, U.S. citizens were shocked by the rapid price increase of gasoline

• “California energy crisis” with its rolling blackouts, in 2001 occurred ahead of the gasoline price increase

• Energy crisis: Not new, occurred in historic times

Peak Oil

• Benefits of oil: Undeniable

• Problems associated with oil: Unquestionable

• Peak oil: The time when half of Earth’s oil extracted and used

• Oil: Nonrenewable and being consumed too fast

• Consequences: Growing demands, water pollution, air pollution, global warming; global, economic, and political instability

Peak Oil

Energy Supply and Demand

• Fossil fuels: 90 percent of U.S. energy consumption (10 percent from hydropower and nuclear power)

• Fossil fuels nonrenewable resources

• Fossil fuel peak discoveries in 1960s

• U.S. energy consumption increasing over time. The rate of increase variable: Peak increase during 1950–1974, since then it has slowed down

Energy Supply and Demand

Energy and Energy Units

• Types of energy: Light, electrical, chemical, thermal, mechanical, and nuclear

• Energy unit: Energy capacity to do work

– Joules (J): 1 Newton force applied over 1 m

– 1 gigajoule (GJ) = 109 J,

– 1 exajoule (EJ) = 1018 J ,

– 1 quad (1015 BTU) = 1.055 EJ

• Power: Rate of energy transferred or used

– Watt (W): 1 joule per second (1 J/sec)

– MW (megawatts): 1000 W

Fossil Fuels

• Transformed from the solar energy originally stored

in organic matter

• Organic matter buried and preserved as fossil fuels

• Geologically: Stored in subsurface rock materials

• Types: Coal, petroleum, natural gas

• Environmental impact: Significant impact from

exploration, production, processing, and distribution

Coal Resources

• America has more coal than any other fossil-fuel resource.

• 20 percent of the total U.S. energy consumption

• The United States has more coal reserves than any other single country in the world

• One-quarter of all the known coal in the world is in the United States

• Large coal deposits can be found in 38 of the 50 states

Geology of Coal

• Coal: Transformed plant matter in ancient swamps

– Estuaries, lagoons, low-lying coastal plains or delta environment

• Coal forming process

– Massive dead plants� buried in an anaerobic (O-deficient) environment� peat� prolonged bury and transformation to increase carbon content� coal

Geology of Coal

Classification of Coal

• Based on carbon content and calorific value on combustion

– Lignite, subbituminous, bituminous, anthracite

• With the increase in rank, generally higher carbon content, higher calorific values, less volatile gas, and less moisture content

• Based on sulfur content: low (< 1 percent), medium (1 to 3 percent), and high (> 3 percent)

Coal Distribution and Consumption

• World reserves about 1000 BMT (billion metric tons)

• Relatively evenly distributed throughout the world

• U.S. reserves: 25 percent of the world reserves

• Annual global consumption 5 BMT

• China, United States, and Russian account for 50 percent of total CO2 released

Distribution of Coal (2)

Impact of Coal Mining

• Land disturbances from open-pit and strip mining

• Mining area acid drainage

• Subsidence over subsurface mines

• Surface water and groundwater pollution

• Air pollution from thermoelectric power plant

• Area ecosystem degradation due to mining practice and afterward inadequate land reclamation

Future Use and Environmental

Impacts of Coal

• More and more land will be strip mined

• Disposal of coal ash (5–20 percent of original coal)

• Mining, processing, disposal of mining waste, shipping, burning, and disposing of ash: All potentially adverse to environment

• Fly ash, from burning finely ground coal in a power plant, hazardous

• The use of coal releasing huge amounts of carbon dioxide (CO2) into the atmosphere

• China, the United States, and Russia: The major carbon dioxide contributors

Hydrocarbon: Oil and Gas

• Oil and gas (O&G): Hydrocarbons due to chemical composition of C, H, and O

• Natural gas: Mostly methane (CH4)

• O&G: Formed from transformation of organic matters

• Heavily mined through production wells

• Other forms: Oil shale and tar sands

Geology of Oil and Gas (1)

• Formation of O&G

– Rapid bury�

– Anaerobic environment�

– Biogenic or thermogenic transformation�

– Oil window (approximately 3 to 6 km depth)

– Formation of oil and gas�

– O&G trapped over geologic time in certain structures

Geology of Oil and Gas (2)

Geology of Oil & Gas (3)

Geologic conditions for O&G fields

• Source rock: Fine-grained organic-rich sedimentary rocks, then O&G migrating upward to the reservoir rocks

• Reservoir rock: Porous and permeable rocks

• Cap rock:Impermeable rock as a barrier to trap O&G in place, forming oil fields

Oil & Gas Production

Production: Commonly through wells

• Types of production

– Primary recovery: Pump no more than 25 percent of the petroleum in the field under natural reservoir pressure

– Enhanced recovery: Manipulate reservoir pressure by injecting gases and liquids, 50 to 60 percent of the petroleum

Distribution of Oil and Gas (1)

• Almost exclusively from sedimentary rocks younger than 500 million years

• ~ 85 percent of the total production in less than 5 percent of production fields

• ~ 65 percent of the total production from about 1 percent of the giant fields

• Most giant O&G fields near recently active plate boundaries in the last 70 million years

Distribution of Oil and Gas (2)

Natural Gas

• Larger global reserve, lasting 100 years at current rate of consumption

• The most reserves in Russia and Middle East

• Cleaner fuel than oil and coal

• Methane hydrate: May be future alternative energy source

Coal-Bed Methane

• Coal containing a large amount of methane

• The methane reserves in WY sufficient for the U.S.

natural gas use for 5 years

• Most coal-bed methane shallow and more

economical to drill

• Concerns over extraction processing and

transportation

• Environmental problems associated with production,

such as disposal of salty water, a flammable

process, erosion

Methane Hydrate

• Potential good source of natural gas

• Exist at depths of 1,000 m (3,300 ft) beneath the sea and under permafrost land areas

• White, ice-like compound of methane gas capsulated by frozen water

• Complicated processes for exploration and production due to highly pressurized conditions

• More studies need to be done for exploiting it

Impact of Exploration & Production

• Land disturbance: Access, drilling

• Environmental impact: Production, transportation, and emissions from refinery

• By-products: Salty brine water, evaporation, and waste disposal problems

• Oil field development in sensitive areas

• Blow-outs or fire at oil and gas wells

• Acid rain

Oil Shales and Tar Sands

• Best-known oil shale in the United States found in

Green River Formation

• Approximate 44,000 km2 in CO, UT, and WY

• ~ 2 trillion (MMBOL) in United States, two-thirds of

the world’s oil shale

• Tar sands contain tar oil and asphalt and other

semi-solid or solid petroleum products

• Tar sands not necessarily sandstone, can be shale,

limestone, or unconsolidated sediments

• Largest tar sands: the Athabasca Tar Sands in

Alberta, Canada, ~ 78,000 km2 (2 trillion BOL)

Future of Oil

• Approaching the peak oil time

• About 3 trillion barrels of oil be recovered

• World current consumption rate: 30 billion barrels/yr

• Estimated peak production 2020 to 2050

• Significant oil production in the United States not extend beyond 2090

• Planning, education, research and development on alternative energy sources: Gasification and liquefaction of coal, other renewable sources

Fossil Fuel and Acid Rain

• Acid rain: A regional to global environmental problem

• Both wet and dry acid deposition:

• Sulfur dioxide (SO2) and nitrogen oxides (NOx)

• In the United Sates, about 17 million tons of NOx and 13 million tons of SO2 into the atmosphere

• Geology, climate patterns, type of vegetation, and composition of soil affected

Fossil Fuel and Acid Rain

Nuclear Energy

• 440 nuclear reactors provide 16 percent global electricity needs

• Mostly from fission of U-235, 0.7 percent concentration naturally, enriched to 3 percent before used in a reactor

• Fission of 1 kg of U equivalent to the burning of 16 metric tons of coal

Geology and Distribution of U

• Average natural concentration 2 ppm

• Must have a concentration factor of 400 to 2500 times to be mined at a profit

• Three types of common deposits: Sandstone impregnated with U, veins of U-bearing materials, and old placer deposits

Reactor

• Most of the reactors: Burner reactors

• Four main components of burner reactors: Core, control rods, coolant, and reactor vessel

• Trend of smaller reactors with less complex in design and gravity-influenced cooling system (passively safe)

• Gas-cooled reactor, “pebble-bed reactor,” to be available in the next few years, preventing the risk of core meltdown and providing optimal energy production

Risks with Fission Reactors

• Various amounts of radiation to environment, from mining, processing, transportation, and before transportation

• Potential nuclear reactor accidents, TMI and Chernobyl

• Nuclear weapons, terrorist activity, and possibly war

• Disposal of nuclear wastes

Nuclear Energy from Fusion

• Combining lighter elements to produce heavier ones, releasing energy

• The Sun and other stars: Huge nuclear fusion reactors

• Nuclear fusion: Research objective, not a commercial reality yet

• Environment: Little radioactive waste, unlimited supply

• Technology: Under the development

Geothermal Energy

• Extracting energy associated with heat and pressure from natural hot water and steam

• Generating electricity at many sites of world or heating energy for buildings, etc.

• Vast amount of geothermal energy resources (500 times of oil and gas resources), only 1 percent could be captured from upper 10 km

Risks with Geothermal Energy

• Overall, environmentally friendly with a great potential for the future energy

• Expensive production process

• Thermal pollution from hot waste waters

• Land subsidence

• At present, relatively local and regional operations

Renewable Energy Sources

• Solar energy: Rapid growing

• Hydropower: Hydroelectric, tidal power

• Biofuels: Wood, charcoal, burning of municipal waste, currently only 1 percent U.S. municipal wastes recovered for energy and 10 percent can be extracted, 30 to 50 percent of wastes for energy in western Europe

• Wind power: Less than 1 percent global electricity demand, but 10 percent potential in a few decades

Conservation, Efficiency, and

Cogeneration

• Highly variable future supply of and demand for energy

• Need to minimize energy demand and adjust energy uses

• Increase energy efficiency through improved or new technologies

• Cogeneration: Capture and use some of the waste heat, rather than direct release to the atmosphere

Energy Policy for the Future

• Hard path: Continuing “business as usual”

– Environmental problems due to use of local resources, and industrialization and technology bringing solutions to the problems

– Dominate energy planning in the United States

• Soft path: Emphasis on energy alternatives

– Renewable, flexible, decentralized, and environmentally more benign than those of the hard path

Sustainable Energy Policy

• Energy planning for the future is complicated

• Necessary to find useful long-term sources of energy without causing atmospheric pollution

• Transition from the hard to soft path involving continued use of fossil fuel

• Energy path: Satisfying modern society needs without endangering the planet

Critical Thinking Topics

• Sustainable energy development means an energy

policy and energy sources without harming the

environment. Do you think this is possible?

• Is it possible that new technology will be able to

make fossil-fuel burning a clean process? Explain

• Speculate the possibility of power plants in space

• List specific actions that an individual citizen can

take to conserve energy and reduce environmental

impact

End of Chapter 16