Energy & Resources Renewable & Nonrenewable. Chapter 16 Nonrenewable Energy.

Energy & Resources Renewable & Nonrenewable

Chapter 16Nonrenewable Energy

Global Energy Consumption

• Total energy consumption (x 1015 BTU’s) Total world consumption 472.3 x1015 BTU’s (British Thermal Units)

United States101.6 BTU

China 77.8 BTU

Russia 30.4 BTU

Japan 22.5 BTU

India 19.1 BTU

Germany14.2 BTU

Canada13.8 BTU

France 11.2 BTU

United Kingdom9.5 BTU

Brazil10.1 BTU

Source: EIA 2008 http://www.eia.doe.gov/iea/wecbtu.html

Future Energy Consumption• By 2050 the world population is expected to reach 9-10 billion people. Most of

this population growth will occur in developing countries.

• World energy consumption is expected to increase by at least 50%. Again, most of this increase will occur in developing countries.

• Beyond 2030, fossil fuels will not be able to keep up with world energy demands.

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From International Energy Agency figuresPredicted energy demand

World Energy Resources• All energy on Earth ultimately

comes from the Sun.• Energy from the Sun may be used

directly, such as:solar electricity panels, solar water heating

• Energy gain indirectly from the Sun includes:

Biomass, wind power (air movements caused by unequal heating of the Earth’s surface) oil, coal, natural gas, & nuclear energy (uranium)

The energy of the Sun can be turned directly into electricity.

The nuclear material used in nuclear reactors came from the material that formed the Sun.

TYPES OF ENERGY RESOURCES

• About 76% of the commercial energy we use comes from nonrenewable fossil fuels (oil, natural gas, and coal) with the remainder coming from renewable sources.

TYPES OF ENERGY RESOURCES

• Commercial energy use by source for the world (left) and the U.S. (right).

Energy From theEarth’s Crust

Oil and Natural Gas

Oil well

Floating oil drilling platform

Pump

Pipeline

Oil drilling platforms

Gas well

Impervious rock Natural gas

Oil

Coal seam

Geothermal

Pipeline

Drilling tower

Hot water storage

Water brought up as steam

Geothermal power plant

Water penetrating through rock is heated

and forms a geothermal reservoir

Coal

Underground coal mine

Contour strip mining

Area strip mining

Nuclear Fission

Cooling towers Fission

Reactor

Magma

Creating Electricity• Commercial electricity is made by the turning of

magnets or electromagnets inside casings of coiled copper wired.

• The magnets are connected to a turbine which is turned by the force of steam, water or wind flowing past it.

Heat source

Turbine

Wire coils

Magnets

Transformer

Non-Renewable Energy• Non renewable energy comes from sources

that cannot be replaced (in our lifetime) within relatively short spans of time including natural gas, oil and coal, as well as radioactive materials.

• Most of the coals and oil used in industry today formed during the Carboniferous period, 350 and 290 million years ago.

Because these fuels formed so long ago and are the remnants of living organisms, they are termed fossil fuels.

• Nuclear power gains its energy from atoms that formed billions of years ago and were trapped in the Earth when it formed.

Coal fired power station

Nuclear power station

Fossil Fuels• Energy conversion – chemical to electrical, heat or

mechanical• Only about 30% efficient • Benefits – easy to use, currently abundant• Costs – a nonrenewable resource, produces

pollutants that contribute to acid rain and the greenhouse effect

• Oil- Supplies the most commercial energy in the world today. People in the U.S. use 23 barrels of petroleum per person or 6 billion barrels total each year!!!

Using Non-Renewable Energy and Resources

• Advantages of using non-renewable energy and resources include:

Convenience of a naturally occurring energy sourceEasy to transport and storeAble to be used to many different applicationsLarge amounts of energy are produced from small amounts of resource

Non renewable fuels such as uranium for nuclear power plants produce huge amounts of energy. One gram of uranium can produce around 80 billion joules.

Oils and gases allow for convenient fuel storage and portability, combined with adaptability.

Using Non-Renewable Energy• Disadvantages of using non-

renewable energy and resources include:

Production of large scale pollutionLocal environment is often heavily damagedResources become difficult to extract as resources are depletedResources may be strategically vulnerable (controlled by external parties or countries)

Acid drainage can cause major pollution in waterways and aquifers.

Coal produces NOx, SO2 in the air as well as toxic particulate matter like mercury, arsenic and lead.

Oil spills can have short and long term negative effects on the environment and organisms.

Electrical Power Consumption

United States2,884 kWh

Germany364 kWh

Japan633.7 kWh

South Korea234 kWh

Australia217.9 kWh

South Africa216 kWh

United Kingdom280 kWh

Russia619 kWh

China2,225 kWh

Electricity use per country (billion kWh)

India565.8 kWh

• Fossil fuels supply about 60% of world electricity needs, as well as other energy uses such as heating and transport.

Source: EIA http://www.eia.doe.gov/iea/elec.html 2008

Core Case Study: How Long Will the Oil Party Last?

• Saudi Arabia could supply the world with oil for about 10 years.

• The Alaska’s North Slope could meet the world oil demand for 6 months (U.S.: 3 years).

• Alaska’s Arctic National Wildlife Refuge would meet the world demand for 1-5 months (U.S.: 7-25 months).

Oil and Gas Reserves

Major oil and gas reserves

‣ World fossil fuel estimates vary but are in the order of 175,000 billion m3 of natural gas & 197.6 billion m3 of oil.

‣ The Middle East accounts for over 50% of proven reserves

‣ Current oil use will allow about 50 more years of energy

Saudi Arabia #1 20% Proven

Reserves

Canada #2 12% Proven

Reserves Iran #3, Iraq #4, Kuwait #5 27% Proven Reserves

N. American Oil & Gas Reserves

Major North American oil and gas deposits

Alberta

Gulf Coast

Scotia shelf

Appalachian

Cordilleran Overthrust belt

OIL• Crude oil (petroleum) is a thick liquid containing

hydrocarbons that we extract from underground deposits and separate into products such as gasoline, heating oil and asphalt.– Only 35-50% can be economically recovered from a

deposit.– As prices rise, about 10-25% more can be recovered

from expensive secondary extraction techniques.• This lowers the net energy yield.

Oil and Natural Gas• Oil and natural gas are both mixtures of

hydrocarbons, molecules comprised of only hydrogen and carbon atoms.

• Natural gas consists of hydrocarbons containing 4 or less carbon atoms.

• Oil contains hydrocarbons with5 or more carbon atoms and many substances like nylon, DDT, polystyrene, and asphalt are derived from petroleum.

Natural gas

Oil

OIL

• Refining crude oil:– Based on boiling

points, components are removed at various layers in a giant distillation column.

– The most volatile components with the lowest boiling points are removed at the top.

Figure 16-5

OIL

• Eleven OPEC (Organization of Petroleum Exporting Countries) have 78% of the world’s proven oil reserves and most of the world’s unproven reserves.

• After global production peaks and begins a slow decline, oil prices will rise and could threaten the economies of countries that have not shifted to new energy alternatives.

Case Study: U.S. Oil Supplies

• The U.S. – the world’s largest oil user – has only 2.9% of the world’s proven oil reserves.

• U.S oil production peaked in 1974 (halfway production point).

• About 60% of U.S oil imports goes through refineries in hurricane-prone regions of the Gulf Coast.

Heavy Oils from Oil Sand and Oil Shale: Will Sticky Black Gold Save Us?

• Heavy and tarlike oils from oil sand and oil shale could supplement conventional oil, but there are environmental problems.– High sulfur content.– Extracting and processing produces:

• Toxic sludge• Uses and contaminates larges volumes of water• Requires large inputs of natural gas which reduces net

energy yield.

Non-conventional Oil• Oil may be locked in materials that

make extraction through drilling impossible. Non-conventional oils include:

oil-sands or tar-sands

oil shale

extra heavy oil (high specific gravity)• Because of the high viscosity of these

kinds of oil reserves, extracting them relies on two techniques:

strip mining - the oil sands and shales are dug from the ground and removed for refiningin situ extraction - steam or a solvent is injected into the sands to allow the oil to flow for pumping

Pyrolysis (chemical decomposition by heating) makes heavy oil or bitumen into useful oil products.

The viscous oil in oil shale becomes fluid when heated.

Oil Shales

• Oil shales contain a solid combustible mixture of hydrocarbons called kerogen.

Figure 16-9

Core Case Study: How Long Will the Oil Party Last?

• We have three options:– Look for more oil.– Use or waste less oil.– Use something else.

Figure 16-1

NATURAL GAS

• Natural gas, consisting mostly of methane, is often found above reservoirs of crude oil.– When a natural gas-field is tapped, gasses are

liquefied and removed as liquefied petroleum gas (LPG).

• Coal beds and bubbles of methane trapped in ice crystals deep under the arctic permafrost and beneath deep-ocean sediments are unconventional sources of natural gas.

NATURAL GAS

• Russia and Iran have almost half of the world’s reserves of conventional gas, and global reserves should last 62-125 years.

• Natural gas is versatile and clean-burning fuel, but it releases the greenhouse gases carbon dioxide (when burned) and methane (from leaks) into the troposphere.

Natural Gas Extraction• Natural gas often occurs in the same

areas as oil. The equipment used to drill for and extract the gas is similar to that used for oil.

• Storage and transport from the drilling rig is a major problem with natural gas.

On land, the gas can sometimes be piped to areas of use. Offshore rigs require specialized shipping that can store the gas at its condensing point of -162oC.

Because natural gas is difficult to store and ship, a large proportion of it is burnt at the well as waste product or re-injected into the well to maintain pressures.

Natural gas burns cleaner and thus produces less pollutants than oil and coal.

Waste gas is burnt at the well. This produces unnecessary pollution and wastes a valuable

energy source.

A L.N.G. (Liquid Natural Gas) carrier unloading.

Hydraulic Fracturing• The process of initiating, and

subsequently propagating a fracture in a rock layer, employing the pressure of a fluid as the source of energy.

• Extended by internal fluid pressure, “fracking”, opens up a fracture and causes it to extend through the rock.

• The fracture width is typically maintained after the injection by introducing a proppant into the injected fluid. Proppant is a material, such as water, grains of sand, ceramic, or other particulates, that prevent the fractures from closing when the injection is stopped.

Underground view of hydraulic fracturing to aid in the removal of natural gas.

Coal• Coal – formed from ancient peat bogs (swamps) that

were under pressure as they were covered.• Used for electricity, heat, steel, exports, and industry,

may contribute to the “Greenhouse Effect”• Four types of coal exist: lignite (soft, used for

electricity), bituminous and subbituminous (harder, also used for electricity) and anthracite (hardest, used for heating)

• 50% of all the coal is in the United States, the former Soviet Union and China

Specific Nonrenewable Resources

Coal Fired Power• World coal consumption was approximately 6,743,786,000 short tons

in 2006 and is expected to increase to 9.98 billion short tons.• China produces 2.38 billion tons which accounted for 68.7% of

electricity production and the US produced 595 million tons which accounted for 44.8% of electricity production.

• Besides the CO2, CO and other greenhouse gas emissions, the majority of atmospheric mercury is produced by coal-burning power plants. Also, sulfur oxides are produced mostly by coal burning power plants which can lead to acid deposition.

Generalized Coal Fired Power Plant 30-

40% EfficientChina and the US accounted for over 50% of the global consumption of coal and used that coal primarily for electricity.

Coal Reserves

Major coal reserves

‣World fossil fuel estimates vary but are in the order of 900,000 billion tonnes of coal.

‣Current coal use will allow about 150 years of energy use

USA #1 Reserves 27% of

total

Russia #2 Reserves 17% of

total

China #3 Reserves 13% of

total

North American Coal ReservesNorthern Great Plains region

San Juan basin

Bighorn basin

Black Mesa field

Green River basin

Western Interior basin

Appalachian basin

Gulf Coast lignite

Major North American coal deposits

Coal is a solid fossil fuel that is formed in several stages as the buried remains of land plants that lived 300-400 million years ago.

Fig. 16-12, p. 368

Increasing heat and carbon content

Increasing moisture content

Peat (not a coal)

Lignite (brown coal)

Bituminous

(soft coal)

Anthracite

(hard coal)Heat Heat Heat

Pressure Pressure Pressure

Partially decayed plant matter in swamps and bogs; low heat content

Low heat content; low sulfur content; limited supplies in most areas

Extensively used as a fuel because of its high heat content and large supplies; normally has a high sulfur content

Highly desirable fuel because of its high heat content and low sulfur content; supplies are limited in most areas

Fig. 16-13, p. 369

Waste heat

Coal bunker TurbineCooling tower

transfers waste heat to

atmosphere

Generator

Cooling loop

Stack

Pulverizing mill

Condenser Filter

Boiler

Toxic ash disposal

COAL

• Coal reserves in the United States, Russia, and China could last hundreds to over a thousand years.– The U.S. has 27% of the world’s proven coal

reserves, followed by Russia (17%), and China (13%).

– In 2005, China and the U.S. accounted for 53% of the global coal consumption.

Surface Mining• Coal, usually bituminous, that is near the surface

can be economically extracted using open cuts in the earth.

•

• The alteration of the land and production of acid mine drainage can lead to acid pollution of soil, waterways and aquifers, reduced plant growth and reduced animal distribution.

Area (strip) mining removes overburden in long cuts

Mountain top removal exposes coal

Contour mining follows the land’s natural shapeCoal seams

exposed

Highly erodible highwall remains

Land provides economic and

technical difficulties

Coal Mining• Surface mining includes area or strip mining

mountaintop removal and contour mining.Surface mining involves the removal of overburden, the rock and material lying on top of the proposed site.

The initial overburden may be removed to another site while subsequent overburden is used as backfill once the coal has been removed.

Surface mining often requires the use of extremely large machines for removal of the overburden and the coal.

The returning of the rock material and topsoil to a site is called reclamation.

Removal of overburden requires large and expensive

machinery.

The exposed coal seam can be easily removed for processing.

• Underground mining uses two main methods:

room / pillar mining. They both remove blocks of the coal seam while leaving others to act as pillars to keep the roof stable.

long wall mining uses machines that move along the length of the coal face. The removed coal falls onto a conveyor that takes it to the surface. As the machine moves forward the tunnel behind it is allowed to collapse.

• Hazards include danger to miners and black lung, a disease caused by prolonged exposure to coal dust

Photo: Eickhoff Maschinenfabrik and Eisengießereihttp://www.eickhoff-bochum.de/de/

Coal Mining

Reclamation• Under the Surface Mining Control and

Reclamation Act of 1977, environmental standards that must be followed during reclamation.

• Land reclamation is the process to make new land. Steps include:

Recontouring / regrading land to its original topography.

Replacing or adding topsoil or nutrients as needed to improve soil.

Replanting with native vegetation/fast growing species/early successional species.

Monitoring for either 5 or 10 years.

2009

1984

1984

2009

Advantages of Fossil Fuels

• Cogeneration: Using fossil fuels for manufacturing and using the waste heat to produce electricity.

• Advantages of fossil fuels include:easy to store and transporthigh net energy productionwell established distribution systemslow air pollution (in natural gas and clean liquid fuels)huge possible reserveswell developed extraction technologies

The ease at which fossil fuels can be refined makes them ideal for the transport industry.

High net energy released by fossil fuels allows large amounts of electricity to be produced

cheaply.

Disadvantages of Fossil Fuels

• Disadvantages of using fossil fuels include:

fixed supply and therefore must eventually run outhigh air pollution when used inefficientlyhigh CO2 emissions even when burned cleanlycan cause severe land and wildlife damage when mishandledrelatively high economic and environmental cost of extraction

Exhaust from vehicles produces around 10% of the world’s air pollution.

Accidental oil spills cause huge damage to marine wildlife.

Fossil Fuel Emissions• The world’s power demands are expected

to rise. Since coal power generates most of the electricity the number of coal power plants is expected to rise.

• Oil is mostly used in transportation and the number of cars is expected to rise as well. The environmental problems associated with coal and oil power are most attributed to the emission of gases including:

Carbon dioxide (CO2) leads to global climate change leading to heath and

environmental effects.

Particulate matter leads to health issues including respiratory disease.

Sulfur oxides (SOx) from coal which leads to acid deposition can effect

the pH of an ecosystem and can also lead to respiratory issues.

Fallout of heavy metals such as mercury, lead, and arsenic.

Environmental degradation can also be associated with transportation of resources, building of processing facilities, and power plants.

Nuclear Power Generation

‣ 79% of nuclear power stations are found in just ten countries.

‣ Accounts for 15% of World Power

1. United States101,119 MW

2. France63,470 MW

3. Japan46,236 MW

Russia21,740 MW

Germany20,339 MW

South Korea17,716 MW

Ukraine13,170 MW

Canada12,600 MW

United Kingdom11,035 MW

Sweden9,016 MW

Source: http://en.wikipedia.org/wiki/Nuclear_power_by_country 2008

Nuclear Power Plants• Approximately 70 countries have at least 1 nuclear power station

contributing to a total production of 14% of the world’s electrical energy needs from 439 nuclear power stations.

Uranium 235

Barium 141 Krypton 92ENERGY

CountryNumber of Reactors

United States 104

France 59

Japan 55

Russia 31

South Korea 20

United Kingdom 19

Canada 18

Germany 17

Ukraine 15

Sweden 10

Total 348

NUCLEAR ENERGY

• When isotopes of uranium and plutonium undergo controlled nuclear fission, the resulting heat produces steam that spins turbines to generate electricity.– The uranium oxide consists of about 97%

nonfissionable uranium-238 and 3% fissionable uranium-235.

– The concentration of uranium-235 is increased through an enrichment process.

Nuclear Power Generation• Nuclear power plants use the spontaneous fission (splitting) of

atoms of uranium-235 or plutonium-239 to produce heat.• The heat is used to turn water into steam which then drives a

turbine connected to a generator.

Cooling tower

Reactor building Powerhouse

The Powerhouse• The steam produced from the heat exchanger in the reactor drives

the steam turbines in the powerhouse but also creates large amounts of thermal pollution.

Water pumpWater pump

Steam turbine Generator Cooling tower

Cold water

Condenser

Steam

Fig. 16-16, p. 372

Small amounts of radioactive gases

Uranium fuel input (reactor core)

Control rodsContainment shell

Heat exchanger

Steam Turbine Generator

Waste heat

Electric power

Hot coolant

Useful energy 25%–30%Hot

water outputPumpPump

Coolant Pump Pump

Moderator

Cool water input

Waste heat

Shielding Pressure vessel

Coolant passage

Water CondenserPeriodic removal and storage of radioactive wastes and spent fuel assemblies

Periodic removal and storage of radioactive liquid wastes

Water source (river, lake, ocean)

• Wastes include waste water that has been through the power plant and has a higher temperature. Radioactive materials can also enter waterways from several sources, including mining and processing of radioactive minerals such as uranium, plutonium and thorium.

Thermal pollution is a common consequence of nuclear power. Water is withdrawn from cooling towers and condensers and released back into the waterway creating a thermal plume. Thermal pollution reduces dissolved oxygen levels and may compromise sensitive species. Ionizing radiation or radioactive substances are used by nuclear power plant and the nuclear weapons industries, but also by medical and scientific research facilities.

Nuclear Pollution

Power plant releases heated water into San

Francisco Bay

Power plants built near water

NUCLEAR ENERGY

• After three or four years in a reactor, spent fuel rods are removed and stored in a deep pool of water contained in a steel-lined concrete container.

Figure 16-17

NUCLEAR ENERGY

• After spent fuel rods are cooled considerably, they are sometimes moved to dry-storage containers made of steel or concrete.

Figure 16-17

What Happened to Nuclear Power?• After more than 50 years of development and

enormous government subsidies, nuclear power has not lived up to its promise because:– Multi billion-dollar construction costs.– Higher operation costs and more malfunctions

than expected.– Poor management.– Public concerns about safety and stricter

government safety regulations.

Case Study: The Chernobyl Nuclear Power Plant Accident

• The world’s worst nuclear power plant accident occurred in 1986 in Ukraine.

• The disaster was caused by poor reactor design and human error.

• In 2006, estimated death toll 90,000• 350,000 people had to abandon their homes• Radioactive fallout 400 times greater than

atomic bomb dropped on Hiroshima, Japan

Fig. 16-20, p. 376

Coal vs. Nuclear

Trade-Offs

Coal Nuclear

Ample supply Ample supply of uranium

High net energy yield Low net energy yield

Very high air pollutionLow air pollution (mostly from fuel reprocessing)

High CO2 emissions Low CO2 emissions (mostly from fuel reprocessing)

High land disruption from surface mining Much lower land disruption

from surface mining

Low cost (with huge subsidies) High cost (even with huge subsidies)

High land use Moderate land use

• Advantages of nuclear power include:

large fuel supply little amounts of fuel needed to produce large amounts of energyfew direct environmental impactslow air pollution (low CO2 emissions)low risk due to multiple safety systems

Advantages of Nuclear Power

Generation

Disadvantages of Nuclear Power• Disadvantages of nuclear

power include:high start up costschance of catastrophic environmental damage if accidents occurremoval and storage of waste presents large technological problemsdecommissioning old plants presents waste problemsthe technology can be adapted to produce nuclear weapons

The Chernobyl accident occurred because of poor safety systems and practices. The explosion contaminated a large area and forced thousands permanently from their homes.

Fukushima Daiichi nuclear power plant during a recovery phase after a tsunami.

NUCLEAR ENERGY

• Terrorists could attack nuclear power plants, especially poorly protected pools and casks that store spent nuclear fuel rods.

• Terrorists could wrap explosives around small amounts of radioactive materials that are fairly easy to get, detonate such bombs, and contaminate large areas for decades.

NUCLEAR ENERGY• When a nuclear reactor reaches the end of its

useful life, its highly radioactive materials must be kept from reaching the environment for thousands of years.

• At least 228 large commercial reactors worldwide (20 in the U.S.) are scheduled for retirement by 2012.– Many reactors are applying to extent their 40-year

license to 60 years.– Aging reactors are subject to embrittlement and

corrosion.

NUCLEAR ENERGY

• Building more nuclear power plants will not lessen dependence on imported oil and will not reduce CO2 emissions as much as other alternatives.– The nuclear fuel cycle contributes to CO2

emissions.– Wind turbines, solar cells, geothermal energy, and

hydrogen contributes much less to CO2 emissions.

NUCLEAR ENERGY

• Scientists disagree about the best methods for long-term storage of high-level radioactive waste:– Bury it deep underground.– Shoot it into space.– Bury it in the Antarctic ice sheet.– Bury it in the deep-ocean floor that is geologically

stable.– Change it into harmless or less harmful isotopes.

Nuclear

• Description – using fission to split large uranium atoms into smaller products and releasing tremendous amounts of heat energy which is used to make steam that turns turbines to create electricity

• Energy conversion – nuclear to electrical and heat• Benefits – pollution-free, very, very efficient• Costs – risk of accidents (spread of radioactivity);

transportation and disposal of radioactive wastes (Nimby!) It also produces a ton of thermal pollution!

Summary of Non-Renewable

CoalCapital cost per kW: LowElectricity cost per kWh: LowR high net energy productionS greenhouse emissions

Natural gasCapital cost per kW: LowElectricity cost per kWh: HighR high net energy productionS greenhouse emissions

NuclearCapital cost per kW: HighElectricity cost per kWh: LowR no greenhouse emissionsS radioactive waste

Information source: Scientific American 2009

Oil (petroleum)Capital cost per kW: LowElectricity cost per kWh: HighR high net energy production S greenhouse emissions

Thermal pollution created and questions raised about safety & storage of waste.

Peat, lignite, bituminous, and anthracite burning causes sulfur and heavy metals

Less greenhouse emission than coal or oil but difficult to transport.

Widely used because of easy transfer and separated by boiling points.

The burning of fossil fuels contributes to the net increase in atmospheric carbon (and the greenhouse effect) by releasing sequestered underground carbon.