17THMILLER/SPOOLMAN

LIVING IN THE ENVIRONMENT

Chapter 15Nonrenewable Energy

Case Study: A Brief History of Human Energy Use

• Everything runs on energy

• Industrial revolution began 275 years ago, relied on

wood, which led to deforestation

• Early energy crisis lead to use of Coal

• Then Petroleum products

• Eventually Nuclear Power and Natural gas

• All of these are nonrenewable energy resources

Energy Use: World and United States

Fig. 15-1, p. 370

Basic Science: Net Energy Is the Only Energy That Really Counts (1)

First law of thermodynamics:Energy cannot be created or destroyed.• It takes high-quality energy to get high-quality energy• Pumping oil from ground, refining it, transporting it

**You can’t get something for nothing….**

Figure 15.2: We can pump oil up from underground reservoirs on land (left) and under the sea bottom (right). Today, high-tech equipment can tap into an oil deposit on land and at sea to a depth of almost 11 kilometers (7 miles). But this requires a huge amount of high-quality energy and can cost billions of dollars per well. For example, the well that tapped into BP’s Thunder Horse oil field in the Gulf of Mexico at water depths of up to 1.8 kilometers (1.1 miles) took almost 20 years to complete and cost more than $5 billion. And as we saw in 2010 with the explosion of a BP deep-sea oil-drilling rig such as that shown here, there is a lot of room for improvement in deep-sea drilling technology.

Basic Science: Net Energy Is the Only Energy That Really Counts (2)

Second law of thermodynamicsEnergy can change form. When it does, some energy is

lost or becomes unavailable for future use.• Some high-quality energy is wasted at every step• The entropy of a closed system increases with time (or

no process of energy transformation can be 100% efficient). This implies that energy sources have different qualities in terms of usability.

**You can’t break even….**

Basic Science: Net Energy Is the Only Energy That Really Counts (3)

Net energy • Total amount of useful energy available from a

resource minus the energy needed to make the energy available to consumers(what is used/wasted)

• Business net profit: total money taken in minus all expenses

Net energy ratio: ratio of energy produced to energy used to produce it

Conventional oil: high net energy ratio

Net Energy Ratios

Fig. 15-3, p. 373

Fig. 15-3a, p. 373

Space HeatingPassive solar 5.8

Natural gas 4.9

Oil 4.5

Active solar 1.9

Coal gasification 1.5

Electric heating (coal-fired plant) 0.4

Electric heating (natural-gas-fired plant) 0.4

Electric heating (nuclear plant) 0.3

Fig. 15-3b, p. 373

High-Temperature Industrial Heat

Surface-mined coal 28.2

Underground- mined coal 25.8

Natural gas 4.9

Oil 4.7

Coal gasification 1.5

Direct solar (concentrated) 0.9

Fig. 15-3c, p. 373

Transportation

Natural gas 4.9

Gasoline (refined crude oil)

4.1

Biofuel (ethanol) 1.9

Coal liquefaction 1.4

Oil shale 1.2

Energy Resources With Low/Negative Net Energy Yields Need Marketplace Help

• Cannot compete in open markets with alternatives that have higher net energy yields

• Need subsidies from taxpayers (government)

• Nuclear power as an example – large amounts of Energy needed at each step

Reducing Energy Waste Improves Net Energy Yields and Can Save Money

• 84% of all commercial energy used in the U.S. is wasted• 43% after accounting for second law of

thermodynamics• We drive inefficient cars/gas guzzlers• We use inefficient coal-burning and

nuclear power plants to produce 2/3 of our electricity

• We know how to fix energy waste – and by doing this we save $, reduce emissions and decrease our dependence on imported oil

We Depend Heavily on Oil (1)

• Petroleum, or crude oil: conventional, or light oil (~30% of world’s supply)

• Unconventional oil (very heavy ~ %70 of supply)

• Fossil fuels: coal, oil, natural gas• Deposits of conventional crude

oil and natural gas often are trapped together under domes deep within the Earth’s crust under land or seafloor

We Depend Heavily on Oil (2)

• Peak production: time after which production from a well declines Disagreement whether we have reached global

peak production for all world oil or not

We Depend Heavily on Oil (3)

• Oil extraction and refining By boiling point temperature

• Petrochemicals: Products of oil distillation Raw materials for industrial organic chemicalsPesticidesPaintsPlastics

Science: Refining Crude Oil

Fig. 15-4, p. 375

Figure 15.4: Science. When crude oil is refined, many of its components are removed at various levels, depending on their boiling points, of a giant distillation column (left) that can be as tall as a nine-story building. The most volatile components with the lowest boiling points are removed at the top of the column. The photo above shows an oil refinery in the U.S. state of Texas.

How Long Might Supplies of Conventional Crude Oil Last? (1)

• World consumption has been growing rapidly since 1950

• Largest consumers in 2009• United States, 23%• China, 8%• Japan, 6%

How Long Might Supplies of Conventional Crude Oil Last? (2)

• Proven oil reservesIdentified deposits that can be extracted profitably

with current technology

• Unproven reservesProbable reserves: 50% chance of recoveryPossible reserves: 10-40% chance of recovery

• Proven and unproven reserves will be 80% depleted sometime between 2050 and 2100

World Oil Consumption, 1950-2009

Figure 1, Supplement 2

History of the Age of Conventional Oil

Figure 9, Supplement 9

OPEC Controls Most of the World’s Oil Supplies (1)

• 13 countries (OPEC – Organization of Petroleum Exporting Countries: Algeria, Angola, Ecuador, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, UAE, Venezuela) have at least 60% of the world’s crude oil reserves Saudi Arabia: 20% (largest portion)United States and China (largest users of oil) : 1.5%

• Global oil production leveled off in 2005

• Oil production peaks and flow rates to consumers

OPEC Controls Most of the World’s Oil Supplies (2)

• Three caveats when evaluating future oil supplies1. Potential reserves are not proven reserves2. Must use net energy yield to evaluate

potential of any oil deposit3. Must take into account high global use of

oil

Crude Oil in the Arctic National Wildlife Refuge (ANWR)

Fig. 15-5, p. 376

Figure 15.5: The amount of crude oil that might be found in the Arctic National Wildlife Refuge (right), if developed and extracted over 50 years, is only a tiny fraction of projected U.S. oil consumption. In 2008, the DOE projected that developing this oil supply would take 10–20 years and would lower gasoline prices at the pump by 6 cents per gallon at most. (Data from U.S. Department of Energy, U.S. Geological Survey, and Natural Resources Defense Council)

OPEC Controls Most of the World’s Oil Supplies (3)

Bottom Line: To keep using conventional oil at the projected increasing rate of consumption we must discover proven reserves of conventional oil equivalent to the current Saudi Arabian supply every 5 years. Most oil geologists say this is highly unlikely.

The United States Uses Much More Oil Than It Produces

• Gets 85% of its commercial E from fossil fuels (40% from crude oil)

• Produces 9% of the world’s oil and uses 23%.

• Has only 1.5% of world’s proven oil reserves

• Imports 52% of its oil

• Should we look for more oil reserves?Extremely difficultExpensive and financially risky

U.S. Energy Consumption by Fuel

Figure 6, Supplement 9

Proven and Unproven Reserves of Fossil Fuels in North America

Figure 18, Supplement 8

Conventional Oil Has Advantages and Disadvantages

• Extraction, processing, and burning of nonrenewable oil and other fossil fuelsAdvantagesDisadvantages

Bird Covered with Oil from an Oil Spill in Brazilian Waters

Fig. 15-7, p. 377

Figure 15.7: This bird was covered with oil from an oil spill in Brazilian waters. If volunteers had not removed the oil, it would have destroyed this bird’s natural buoyancy and heat insulation, causing it to drown or die from exposure because of a loss of body heat.

Case Study: Heavy Oil from Tar Sand

• Tar sand (Oil sand) - mixture of clay, sand, water and bitumen (thick, tarlike heavy oil)

• Canada and Venezuela: oil sands have more oil than in Saudi Arabia

• ExtractionSerious environmental impact before strip-miningAir pollutionLow net energy yield: Is it cost effective?

Strip Mining for Tar Sands in Alberta

Fig. 15-8, p. 378

Figure 15.8: Producing heavy oil from Canada’s Alberta tar sands project involves strip-mining areas large enough to be seen from outer space, draining wetlands, and diverting rivers. It also produces huge amounts of air and water pollution and has been called the world’s most environmentally destructive project. For oil from the sands to be profitable, oil must sell for $70–90 a barrel.

Will Heavy Oil from Oil Shales Be a Useful Resource?

• Oil shales contain kerogen (solid mixture of hydrocarbons)• After distillation: shale oil

• 72% of the world’s reserve is in arid areas of western United States (Co, Ut, Wy)• Locked up in rock• Lack of water needed for

extraction and processing• More air pollution• Low net energy yield

Figure 15.9: Shale oil (right) can be extracted from oil shale rock (left). However, producing shale oil requires large amounts of water and has a low net energy yield and a very high environmental impact.

Trade-Offs: Heavy Oils from Oil Shale and Oil Sand

Fig. 15-10, p. 379

15-3 What Are the Advantages and Disadvantages of Using Natural Gas? • Concept 15-3 Conventional natural gas is more

plentiful than oil, has a high net energy yield and a fairly low cost, and has the lowest environmental impact of all fossil fuels.

Natural Gas Is a Useful and Clean-Burning Fossil Fuel (1)

Natural gas: mixture of gases• 50-90% is methane -- CH4

• smaller amounts of propane, butane and hydrogen sulfide

Natural Gas Is a Useful and Clean-Burning Fossil Fuel (2)

Conventional natural gas• Lies above most reservoirs of crude oil• Where found without pipelines – usually burned off

Figure 15.11: Natural gas found above a deep sea oil well deposit or in a remote land area is usually burned off (flared) because no pipeline is available to collect and transmit the gas to users. This practice wastes this energy resource and adds climate-changing CO2, soot, and other air pollutants to the atmosphere.

Natural Gas Is a Useful and Clean-Burning Fossil Fuel (3)

• Liquified under high pressure • Liquefied petroleum gas (LPG) – tanks used

in rural areas• Liquefied natural gas (LNG) – distributed in

gas pipelines• Low net energy yield• Makes U.S. dependent upon unstable

countries like Russia (25% of the reserves) and Iran• U.S. only has 3.4% but uses ~24% of the world’s annual production

Trade-Offs: Conventional Natural Gas

Fig. 15-12, p. 381

Is Unconventional Natural Gas the Answer?

Coal bed methane gas• In coal beds near the earth’s surface• In shale beds• High environmental impacts or extraction

Hydraulic Fracturing Gasland - TrailerMethane hydrate

• Trapped in icy water • In permafrost environments• On ocean floor• Costs of extraction currently too high

Methane in permafrost

Methane Hydrate

Fig. 15-13, p. 381

Figure 15.13: Gas hydrates are crystalline solids that can be burned as shown here. They form naturally from the reaction of various gases (commonly methane) with water at low temperatures and under high pressures. Natural gas hydrates form extensively in permafrost and in sediments just under the sea floors around all of the world’s continents. Methane hydrates, shown here, are a potentially good fuel.

Coal Is a Plentiful but Dirty Fuel (1)

Coal: solid fossil fuel formed from fossilized plant matter by heat and pressure

Stages in Coal Formation over millions of years

Figure 15.14: Over millions of years, several different types of coal have formed. Peat is a soil material made of moist, partially decomposed organic matter and is not classified as a coal, although it too is used as a fuel. The different major types of coal vary in the amounts of heat, carbon dioxide, and sulfur dioxide released per unit of mass when they are burned.

Peat Formationand harvestBog People

Fig. 15-14, p. 382

Coal Is a Plentiful but Dirty Fuel (2)

Burned in power plants; generates 42% of the world’s electricity• Inefficient

NJ has 7 Coal burning power plants – PA has 40.NJ and Coal - check out other states

Science: Coal-Burning Power Plant

Fig. 15-15, p. 382

Figure 15.15: Science. This power plant burns pulverized coal to boil water and produce steam that spins a turbine to produce electricity. The steam is cooled, condensed, and returned to the boiler for reuse. Waste heat can be transferred to the atmosphere or to a nearby source of water. The largest coal-burning power plant in the United States, located in Indiana, burns three 100-car trainloads of coal per day. There are about 600 coal-burning power plants in the United States. The photo shows a coal-burning power plant in Soto de Ribera, Spain.

Coal Is a Plentiful but Dirty Fuel (3)

Three largest coal-burning countries • China• United States• Canada

Coal Consumption in China and the United States, 1980-2008

Coal Is a Plentiful but Dirty Fuel (4)

World’s most abundant fossil fuel• U.S. has 28% of proven reserves

Coal Is a Plentiful but Dirty Fuel (5)

Environmental costs of burning coal• Severe air pollution • Sulfur released as SO2

• Large amount of soot• CO2

• Trace amounts of Hg and radioactive materials

It’s cheap b/c the environmental costs are not included

Figure 15.16: This coal-burning industrial plant in India produces large amounts of air pollution because it has inadequate air pollution controls.

CO2 Emissions Per Unit of Electrical Energy Produced for Energy Sources

Fig. 15-17, p. 383

Figure 15.17: CO2 emissions, expressed as percentages of emissions released by burning coal directly, vary with different energy resources.

World Coal and Natural Gas Consumption, 1950-2009

Figure 7, Supplement 9

Case Study: The Problem of Coal Ash

• Highly toxic• Arsenic, cadmium, chromium, lead, mercury• Ash left from burning and from emissions

• Some used as fertilizer by farmers

• Most is buried or put in ponds• Contaminates groundwater

• Should be classified as hazardous waste

The Clean Coal and Anti-Coal Campaigns

Coal companies and energy companies fought• Classifying carbon dioxide as a pollutant• Classifying coal ash as hazardous waste• Air pollution standards for emissions

2008 clean coal campaign• But no such thing as clean coal

“Coal is the single greatest threat to civilization and all life on the planet.” – James Hansen (climate scientist of the NASA Goddard Center)

We Can Convert Coal into Gaseous and Liquid Fuels

Conversion of solid coal to• Synthetic natural gas

(SNG) by coal gasification

• Methanol or synthetic gasoline by coal liquefaction

• Synfuels

Are there benefits to using these synthetic fuels?

(water usage increased)