definition things human use that have a limited supply...

Nonrenewable Resources

Definition – things human use that

have a limited supply; they cannot be

regrown or replenished by man

Conservation

Definition – using less of a resource or

reusing a resource, ex. refilling plastic

laundry jugs, reusing plastic bags, etc.

Part of the solution

Problems – this requires a change in our

lifestyle and some people will resist.

Dealing with Nonrenewable Resources

Restoration Definition – recycling our resources

Examples – aluminum, glass, tin, steel, plastics,

etc.

Part of the solution

Problems – recycling a resource often costs more

than using the raw material; we don’t have the

technology to recycle everything

Sustainability

Definition – prediction of how long specific

resources will last; ex. we have a 200 year

supply of coal in the U.S.

Knowing this helps people make decisions in

resource use

Problems – these are only predictions; they may

not be accurate

ENVIRONMENTAL EFFECTS OF

USING MINERAL RESOURCES

The extraction, processing, and use of mineral

resources has a large environmental impact.

Figure 15-9

Fig. 15-10, p. 344

Natural Capital Degradation

Extracting, Processing, and Using Nonrenewable Mineral and Energy Resources

Steps Environmental effects

Mining Disturbed land; mining accidents; health hazards, mine waste dumping, oil spills and blowouts; noise; ugliness; heat

Exploration,

extraction

Processing

Solid wastes; radioactive material; air, water, and soil pollution; noise; safety and health hazards; ugliness; heat

Transportation,

purification,

manufacturing

Use

Noise; ugliness; thermal water pollution; pollution of air, water, and soil; solid and radioactive wastes; safety and health hazards; heat

Transportation or

transmission to

individual user,

eventual use, and

discarding

Costs Ownership costs – equipment, labor, safety

(insurance), environmental costs (reclamation,

pollution control, air monitors, water treatment, etc.),

taxes

External costs – processing the resource, transporting

the resource

Marginal costs – research: finding new sources of the

resource and new ways to harvest it

Harvesting Nonrenewable Resources

Benefits Direct – money received for resources;

provides many jobs

Indirect – land can be reclaimed

(brought back to original condition)

and sold for profit.

Minerals Defined Mineral Resource- concentration of

naturally occurring material from the

earth’s crust that can be extracted and

processed at an affordable cost

Fossil fuels, metallic minerals, nonmetallic

minerals

Ore- rock that contains large enough

concentration of mineral to make it

profitable for mining and processing

High-grade; low-grade

ENVIRONMENTAL EFFECTS OF

USING MINERAL RESOURCES

Minerals are removed through a variety of methods

that vary widely in their costs, safety factors, and

levels of environmental harm.

A variety of methods are used based on mineral

depth.

Surface mining: shallow deposits are removed.

Subsurface mining: deep deposits are removed.

Methods Surface Mining

Description – if resource is <200 ft. from the surface, the topsoil is removed (and saved), explosives are used to break up the rocks and to remove the resource, reclamation follows

Benefits – cheap, easy, efficient

Costs – tears up the land (temporarily), byproducts produce an acid that can accumulate in rivers and lakes

Extracts 90% of nonfuel mineral and rock resources

Extracts 60% of coal used in the USA

Open-pit Mining Machines dig

holes and

remove ores,

sand, gravel,

and stone.

Toxic

groundwater

can accumulate

at the bottom.

Figure 15-11

Area Strip Mining Earth movers strips

away overburden, and

giant shovels removes

mineral deposit.

Often leaves highly

erodible hills of

rubble called spoil

banks.

Used mostly in flat

areas

Figure 15-12

Contour Strip Mining

Used on hilly or

mountainous

terrain.

Unless the land

is restored, a

wall of dirt is left

in front of a

highly erodible

bank called a

highwall.

Figure 15-13

Mountaintop Removal Machinery removes

the tops of mountains

to expose coal.

The resulting waste

rock and dirt are

dumped into the

streams and valleys

below.

Seen mostly in the

Appalachian Mtns. Figure 15-14

Methods (Continued) Underground Mining

Description – digging a shaft down to the

resource, using machinery (and people) to tear

off and remove the resource

Benefits – can get to resources far underground

Costs – more expensive, more time-consuming,

more dangerous

Methods (Continued)

Reclamation

Description – returning the rock layer

(overburden) and the topsoil to a surface

mine, fertilizing and planting it

Benefits – restores land to good condition

Costs – expensive, time-consuming

How long will they last?

5 countries supply most of the non-renewable

mineral resources used by modern societies.

Factors effecting future supply

Economic depletion

Graph pg. 361

Mining subsidies (US General Mining Law 1872)

Mine lower-grade ores?

Sustainable Use

Substitutes

Recycle/Reuse

Fig. 15-18, p. 351

Solutions

Sustainable Use of Nonrenewable Minerals

• Do not waste mineral resources.

• Recycle and reuse 60–80% of mineral resources.

• Include the harmful environmental costs of

mining and processing minerals in the prices

of items (full-cost pricing).

• Reduce subsidies for mining mineral resources.

• Increase subsidies for recycling, reuse, and

finding less environmentally harmful substitutes.

• Redesign manufacturing processes to use less

mineral resources and to produce less pollution

and waste.

• Have the mineral-based wastes of one

manufacturing process become the raw

materials for other processes.

• Sell services instead of things.

• Slow population growth.

Specific Resources & Their Uses Limestone – abundant locally, formed from layers of

seashells and organisms under pressure as they were covered; used in sidewalks, fertilizers, plastics, carpets, and more

Lead – used in batteries and cars

Clay – used to make books, magazines, bricks, and linoleum

Gold – besides being used as money and for jewelry, gold is used in medicine (lasers, cauterizing agents) and in electronics (circuits in computers, etc.)

Texas

Central – limestone, tin, clay, lead, garnets,

freshwater pearls, amethysts, calcium carbonate

West – talc, mercury, silver, petroleum, sulfur

East – lignite coal, petroleum

South – lignite coal, petroleum, uranium, limestone

North – helium, uranium, petroleum, bituminous

coal

United States

Central – diamonds (Arkansas), bituminous

coal

West – bituminous and subbituminous coal,

gold, silver, copper

East – anthracite coal, bituminous coal

South – some gold (SC), bituminous coal

North – bituminous coal, some gold (SD, WI)

Core Case Study:

How Long Will the Oil Party Last? Supplies 1/3 of the world’s energy

Geologists predict we will have depleted 80% of the

reserves between 2050 and 2100

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).

Commercial Energy

% renewable vs. % non-renewable

3 largest users

Net Energy…understand ratios

Evaluation

Supply

Environmental impact

Useful energy produced

Primary Sources

Definition – the original sources that

are used to make electricity or heat

Energy Resources

Secondary Sources

Definition – the heat and

electricity that we use for energy

Cogeneration

Production of two useful forms of energy,

such as high-temperature heat or steam and

electricity, from the same fuel source.

Ex. An industry using natural gas for

manufacturing and using the waste heat to

produce electricity.

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.

OIL Crude Oil- thick liquid with

hydrocarbons that we extract

from underground deposits.

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

Fig. 16-5, p. 359

Gases

Gasoline

Aviation fuel

Heating oil

Diesel

oil

Naptha

Grease

and wax

Asphalt

Heated

crude oil

Furnace

OIL Eleven OPEC (Organization of Petroleum Exporting

Countries) have at least 60% of the world’s proven oil

reserves and most of the world’s unproven reserves.

Algeria, Angola, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria,

Quatar, Saudi Arabia, UAE, Venezuela.

Since most of the world’s oil is controlled by government

and OPEC’s secrecy, the amout of reserves are very hard

to confirm.

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.

U.S. Oil Supplies The U.S. – the world’s largest oil user – has only 2.4%

of the world’s proven oil reserves.

U.S oil production peaked in 1974 (halfway production

point).

Potential reserves are beneath federal lands or coastal

waters; could significantly boost reserves, price to bring

it to consumer would be huge

$7.50-$10/barrel on land, 4X higher in deep water --

compare to $2/barrel in Saudi Arabia

This is why we import approx. 60% of our oil

Increase recovery & engineered bacteria

U.S. Arctic National Wildlife

Refuge

Not available to drilling/exploration

Alaska’s representatives

Is the benefit worth the cost?

Increase reserves

Degraded land

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.

Bitumen is the combustible organic material

Canada has ¾ of the world’s oil sands, oil sands are considered reserves of conventional oil so Canada has 15% of world’s oil reserves

High sulfur content.

Produces 3x more CO2/barrel than conventional oil

Extracting and processing produces: Toxic sludge

Uses and contaminates larges volumes of water

Requires large inputs of natural gas which reduces net energy yield.

Oil Shales

Oil shales contain a solid

combustible mixture of

hydrocarbons called

kerogen.

72% of estimated reserves

are in the western U.S.

Estimates say reserve could

meet current U.S. oil

demand for 110 years

Low net energy bc most is

locked up in low grade ore,

high environmental impact,

requires a lot of water Figure 16-9

NATURAL GAS Natural gas, consisting mostly of methane, is often

found above reservoirs of crude oil.

Often viewed as an unwanted by-product and burned off

When a natural gas-field is tapped, gasses are liquefied

and removed as liquefied petroleum gas (LPG).

To be transferred across oceans natural gas is converted

to liquefied natural gas (LNG) at low temp and high

pressure

Low net energy yield

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.

Unconventional Natural Gas

Methane hydrate

Found in coal beds near earth’s surface in the U.S. and Canada

Methane trapped in icy structures of water molecules

Buried under tundra/arctic permafrost

Expensive and release of methane is too high

Coal beds methane

Scars the land

Pollution of air and water public backlash in western U.S.

COAL

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.

Largest coal burning countries are China, United States, & India

Produces 49% of the energy in the U.S.

Most abundant fossil fuel, the U.S. is the Saudi Arabia of coal

Dirty fuel; tax each unit of carbon dioxide produced.

Figure 16-12

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 Turbine Cooling tower

transfers waste

heat to

atmosphere

Generator

Cooling loop

Stack

Pulverizing

mill Condenser Filter

Boiler

Toxic ash disposal

COAL

Cheap, plentiful, large distibution

Severe impact on air quality, water, and

land

Can be converted to synthetic natural gas

(SNG)

Coal gasification or liquefication

Requires a lot of coal to creat

TYPES OF ENERGY

RESOURCES

About 99% of the energy we use for heat

comes from the sun and the other 1% comes

mostly from burning fossil fuels.

Solar energy indirectly supports wind power,

hydropower, and biomass.

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

Nonrenewable energy resources and geothermal

energy in the earth’s crust. Figure 16-2

Fig. 16-2, p. 357

Oil and natural gas Floating oil drilling

platform Oil storage Coal

Contour

strip mining Oil drilling

platform on

legs

Geothermal

energy

Hot water storage Oil well

Pipeline Geothermal

power plant

Gas

well Valves Mined coal

Pump Area strip

mining Drilling

tower

Pipeline

Coal seam Water

penetrates

down through

the rock

TYPES OF ENERGY RESOURCES

Commercial energy use by source for the

world (left) and the U.S. (right).

Figure 16-3

REDUCING ENERGY WASTE

AND IMPROVING ENERGY

EFFICIENCY Four widely used devices waste large

amounts of energy:

Incandescent light bulb: 95% is lost as heat.

Internal combustion engine: 94% of the

energy in its fuel is wasted.

Nuclear power plant: 92% of energy is wasted

through nuclear fuel and energy needed for

waste management.

Coal-burning power plant: 66% of the energy

released by burning coal is lost.

USING RENEWABLE SOLAR

ENERGY TO PROVIDE HEAT

AND ELECTRICITY A variety of renewable-energy resources are

available but their use has been hindered by

a lack of government support compared to

nonrenewable fossil fuels and nuclear

power.

Direct solar

Moving water

Wind

Geothermal



AND ELECTRICITY

The European Union had set a goal to get 22% of its electricity from renewable energy by 2010.

Costa Rica gets 92% of its energy from renewable resources.

China aims to get 10% of its total energy from renewable resources by 2020.

In 2004, California got about 12% of its electricity from wind and plans to increase this to 50% by 2030.



AND ELECTRICITY

Denmark now gets 20% of its electricity

from wind and plans to increase this to 50%

by 2030.

Brazil gets 20% of its gasoline from

sugarcane residue.

In 2004, the world’s renewable-energy

industries provided 1.7 million jobs.

Solar

Types – photovoltaic cells (convert sunlight directly to electricity with a 10% efficiency) and solar thermal systems (sun’s heat is used to heat bodies of water enough to produce steam that can be used to make electricity)

Energy conversion – radiant/heat to electrical, heat or mechanical

Benefits – pollution-free, unlimited source

Costs – not useful in cloudy areas or at night, we do not have the technology needed to use very efficiently

Producing Electricity with Solar Cells

Photovoltaic (PV) cells can provide

electricity for a house of building using

solar-cell roof shingles. Figure 17-17

Fig. 17-17, p. 398

Single solar cell Solar-cell roof

–

Boron

enriched

silicon

+

Junction

Phosphorus

enriched silicon

Roof options

Panels of

solar cells

Solar

shingles

Producing Electricity with Solar Cells

Solar cells can be

used in rural

villages with

ample sunlight

who are not

connected to an

electrical grid.

Figure 17-18

Core Case Study: The Coming Energy-

Efficiency and Renewable-Energy

Revolution

It is possible to get electricity from solar

cells that convert sunlight into electricity.

Can be attached like shingles on a roof.

Can be applied to window glass as a coating.

Can be mounted on racks almost anywhere.

Core Case Study: The Coming Energy-

Efficiency and Renewable-Energy

Revolution

The heating bill for this energy-efficient passive solar radiation office in Colorado is $50 a year.

Figure 17-1

Passive Solar

Heating

Passive solar heating

system absorbs and

stores heat from the

sun directly within a

structure without the

need for pumps to

distribute the heat.

Figure 17-13

Fig. 17-13, p. 396

Direct Gain

Summer

sun Hot air

Warm

air

Super-

insulated

windows

Winter

sun

Cool air

Earth tubes

Ceiling and north wall

heavily insulated

Fig. 17-13, p. 396

Greenhouse, Sunspace, or

Attached Solarium

Summer cooling vent

Warm air

Insulated

windows

Cool air

Fig. 17-13, p. 396

Earth Sheltered

Reinforced concrete,

carefully waterproofed

walls and roof

Triple-paned or

superwindows Earth

Flagstone floor for heat

storage

Fig. 17-14, p. 396

Trade-Offs

Passive or Active Solar Heating

Advantages Disadvantages

Energy is free Need access to sun

60% of time Net energy is

moderate

(active) to high

(passive)

Sun blocked by

other structures

Need heat storage

system

Quick installation

No CO2 emissions

Very low air and

water pollution High cost (active)

Very low land

disturbance

(built into roof

or window)

Active system

needs maintenance

and repair

Moderate cost

(passive)

Active collectors

unattractive

Cooling Houses Naturally

We can cool houses by:

Superinsulating them.

Taking advantages of breezes.

Shading them.

Having light colored or green roofs.

Using geothermal cooling.

Wind

Energy conversion – kinetic to electrical

Benefits – pollution-free, source is free (used in West Texas, Hawaii, California, and more)

Costs – can only be used in places with lots of wind

PRODUCING ELECTRICITY

FROM WIND

Wind power is the world’s most promising energy

resource because it is abundant, inexhaustible,

widely distributed, cheap, clean, and emits no

greenhouse gases.

Much of the world’s potential for wind power

remains untapped.

Capturing only 20% of the wind energy at the

world’s best energy sites could meet all the

world’s energy demands.


FROM WIND

Wind turbines can be used individually to produce electricity. They are also used interconnected in arrays on wind farms.

Figure 17-21


FROM WIND

The United States once led the wind power

industry, but Europe now leads this rapidly

growing business.

The U.S. government lacked subsidies, tax breaks and

other financial incentives.

European companies manufacture 80% of the

wind turbines sold in the global market

The success has been aided by strong government

subsidies.

Biomass

Description – any type of organic matter (forest products, crop wastes, animal wastes, people wastes, etc.) that can be used to produce energy; currently used for about 5% of U.S. energy

Energy conversion – chemical to electrical or heat

Benefits – cheap, less toxic pollutants, using wastes effectively, currently used in Rio Grande Valley with the burning of sugar cane residue, also produces food, feed, and fiber

Costs – we don’t have all the technology needed to use this well right now, not useful in every location, some pollution is produced

PRODUCING

ENERGY FROM

BIOMASS

Plant materials and

animal wastes can be

burned to provide heat

or electricity or

converted into

gaseous or liquid

biofuels. Figure 17-23

PRODUCING ENERGY FROM

BIOMASS

The scarcity of

fuelwood causes

people to make

fuel briquettes

from cow dung in

India. This

deprives soil of

plant nutrients. Figure 17-24

Fig. 17-25, p. 405

Trade-Offs

Solid Biomass


Large potential supply in some

areas

Nonrenewable if harvested

unsustainably

Moderate costs Moderate to high environmental

impact

No net CO2 increase if harvested

and burned sustainably

CO2 emissions if harvested

and burned unsustainably

Low photosynthetic efficiency Plantation can be located on

semiarid land not needed for

crops Soil erosion, water pollution,

and loss of wildlife habitat

Plantation can help restore

degraded lands

Plantations could compete

with cropland

Often burned in inefficient

and polluting open fires and

stoves

Can make use of agricultural,

timber, and urban wastes

Water Energy conversion – kinetic to electrical or heat

Benefits – already have the technology to do this, pollution free, dams are also useful as water sources and flood controls; world’s largest source of electrical power

Costs – there are environmental costs to building new dams, there are not rivers located everywhere

Read James Bay Watershed Transfer Project Miller Page 304


FROM THE WATER CYCLE

Water flowing in rivers and streams can be

trapped in reservoirs behind dams and

released as needed to spin turbines and

produce electricity.

There is little room for expansion in the

U.S. – Dams and reservoirs have been

created on 98% of suitable rivers.

Fig. 17-20, p. 400

Trade-Offs

Large-Scale Hydropower


Moderate to high net energy High construction costs

Large untapped potential

High environmental impact

from flooding land to form a

reservoir

High efficiency (80%)

High CO2 emissions from

biomass decay in shallow

tropical reservoirs

Low-cost electricity

Long life span

No CO2 emissions during

operation in temperate areas

Floods natural areas behind dam

May provide flood control below

dam

Converts land habitat to lake

habitat

Danger of collapse

Provides water for year-round

irrigation of cropland

Uproots people

Decreases fish harvest below dam

Reservoir is useful for fishing

and recreation

Decreases flow of natural fertilizer

(silt) to land below dam

Geothermal

Description – heat from deep within the earth is used to produce electricity

This is the only energy source that doesn’t come from the sun!

Energy conversion – thermal to electrical and heat

Benefits – pollution-free, used near Waco and in Iceland

Costs – not available everywhere, we don’t have all the technology needed to use it

GEOTHERMAL ENERGY Geothermal energy consists of heat stored

in soil, underground rocks, and fluids in the

earth’s mantle.

We can use geothermal energy stored in the

earth’s mantle to heat and cool buildings

and to produce electricity.

A geothermal heat pump (GHP) can heat and

cool a house by exploiting the difference

between the earth’s surface and underground

temperatures.

Geothermal Heat Pump

The house is

heated in the

winter by

transferring heat

from the ground

into the house.

The process is

reversed in the

summer to cool

the house. Figure 17-31

Tidal Power

Energy conversion – kinetic to

electrical

Benefits – pollution-free, cheap,

renewable

Costs – only two places in the U.S.

have tides needed to do this

Wave Power

Energy conversion – kinetic to electrical

Benefits – pollution-free, cheap, renewable

Costs - only suitable in areas facing the

open ocean (especially on the West Coasts

of continents); tend to be destroyed in

storms


FROM THE WATER CYCLE

Ocean tides and waves and temperature

differences between surface and bottom

waters in tropical waters are not expected to

provide much of the world’s electrical

needs.

Only two large tidal energy dams are

currently operating: one in La Rance,

France and Nova Scotia’s bay of Fundy

where the tidal amplitude can be as high as

16 meters (63 feet).

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.

Fig. 16-16, p. 372

Small amounts of radioactive gases

Uranium fuel

input (reactor

core)

Control rods

Containment shell

Heat exchanger

Steam Turbine Generator

Waste heat

Electric

power

Useful energy

25%–30% Hot

water

output

Coolant

Moderator

Cool

water

input

Waste heat

Shielding Pressure

vessel

Coolant

passage

Water Condenser Periodic removal and

storage of radioactive

wastes and spent fuel

assemblies

Periodic removal

and storage of

radioactive liquid

wastes

Water source (river,

lake, ocean)

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.

By 2005, 56 people had died from radiation

released.

4,000 more are expected from thyroid cancer

and leukemia.

NUCLEAR

ENERGY

A 1,000

megawatt

nuclear plant is

refueled once a

year, whereas a

coal plant

requires 80 rail

cars a day.

Figure 16-20

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 pollution Low 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

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!

WAYS TO IMPROVE ENERGY

EFFICIENCY

We can save energy in building by getting heat

from the sun, superinsulating them, and using

plant covered green roofs.

We can save energy in existing buildings by

insulating them, plugging leaks, and using

energy-efficient heating and cooling systems,

appliances, and lighting.

Strawbale House

Strawbale is a superinsulator that is made from

bales of low-cost straw covered with plaster or

adobe. Depending on the thickness of the bales, its

strength exceeds standard construction.

Figure 17-9

Living Roofs Roofs covered with

plants have been

used for decades in

Europe and Iceland.

These roofs are

built from a blend

of light-weight

compost, mulch and

sponge-like

materials that hold

water. Figure 17-10

Saving Energy in Existing

Buildings

About one-third of the heated air in typical

U.S. homes and buildings escapes through

closed windows and holes and cracks.

Figure 17-11

Definition

Any fuel that meets certain emissions

standards; i.e. they give off a certain

amount of pollution (or less)

Alternative Fuels

Laws Involved

Clean Air Act amendments of 1990

Energy Policy Act (EPACT) in Texas

of 1992

Such laws have led to more research

and development of these fuels

Examples of Alternative Fuels Biodiesel – made of vegetable oils and

alcohols; expensive

Diesel – cleaner than “normal” gasoline, being more refined

Biogas – by-product of decaying vegetation; need technology

Hydrogen – expensive and we need more technology

Ethanol/Methanol – alcohols; not as efficient (Miles per gallon) and we don’t have all the technology ; also, if our grain supplies are used to make fuel, will we have enough to feed the world?

Natural Gas – expensive and we need more technology

Reformulated Gasoline (RFG) – regular gas that has been further refined to remove some of the more toxic pollutants

Propane – most usable form of alternative fuel; not as efficient (mpg)

Syngas – manmade gas made of hydrogen and carbon monoxide; need more technology to use it

HYDROGEN

Some energy experts view hydrogen gas as

the best fuel to replace oil during the last

half of the century, but there are several

hurdles to overcome:

Hydrogen is chemically locked up in water an

organic compounds.

It takes energy and money to produce it (net

energy is low).

Fuel cells are expensive.

Hydrogen may be produced by using fossil

fuels.

Energy Laws

Public Utility Holding Company Act (PUHCA) – 1935; regulated the interstate flow of energy; 1st law of its kind; a law designed to protect consumers from corporate abuse of electricity markets

(so electric companies can’t price gouge.) This was happening during the great depression.

Corporate Average Fuel Economy Act (CAFÉ) –1975; focused attention on efficiency of cars; mpg stickers required

Public Utility Regulatory Policies Act (PURPA)–1978; higher utility rates for increased electricity use

Converting Plants and Plant Wastes

to Liquid Biofuels: An Overview

Motor vehicles can run on ethanol,

biodiesel, and methanol produced from

plants and plant wastes.

The major advantages of biofuels are:

Crops used for production can be grown almost

anywhere.

There is no net increase in CO2 emissions.

Widely available and easy to store and

transport.

Case Study: Producing Ethanol

Crops such as

sugarcane, corn, and

switchgrass and

agricultural, forestry

and municipal wastes

can be converted to

ethanol. Switchgrass can remove

CO2 from the

troposphere and store it

in the soil. Figure 17-26

Case Study: Producing Ethanol

10-23% pure ethanol makes gasohol which can be

run in conventional motors.

85% ethanol (E85) must be burned in flex-fuel

cars.

Processing all corn grown in the U.S. into ethanol

would cover only about 55 days of current

driving.

Biodiesel is made by combining alcohol with

vegetable oil made from a variety of different

plants..

Case Study: Biodiesel and

Methanol

Growing crops for biodiesel could

potentially promote deforestation.

Methanol is made mostly from natural gas

but can also be produced at a higher cost

from CO2 from the atmosphere which could

help slow global warming.

Can also be converted to other hydrocarbons to

produce chemicals that are now made from

petroleum and natural gas.


EFFICIENCY Average fuel

economy of new vehicles sold in the U.S. between 1975-2006.

The government Corporate Average Fuel Economy (CAFE) has not increased after 1985.

Figure 17-5

Fig. 17-5, p. 388

Cars

Both

Ave

rag

e f

ue

l e

co

no

my

(mil

es

pe

r g

all

on

, o

r m

pg

)

Model year

Pickups, vans, and

sport utility vehicles


EFFICIENCY

General features of a

car powered by a

hybrid-electric

engine.

“Gas sipping” cars

account for less than

1% of all new car

sales in the U.S.

Figure 17-7

Fig. 17-7, p. 389

Regulator: Controls flow of power between electric motor and battery bank.

Fuel tank: Liquid fuel such as gasoline, diesel, or ethanol runs small combustion engine. Transmission:

Efficient 5-speed automatic transmission.

Battery: High-density battery powers electric motor for increased power.

Combustion engine: Small, efficient internal combustion engine powers vehicle with low emmissions; shuts off at low speeds and stops.

Electric motor: Traction drive provides additional power for passing and acceleration; excess energy recovered during braking is used to help power motor.

Fuel Electricity

Hybrid Vehicles, Sustainable Wind

Power, and Oil imports

Hybrid gasoline-electric engines with an

extra plug-in battery could be powered

mostly by electricity produced by wind and

get twice the mileage of current hybrid cars.

Currently plug-in batteries would by generated

by coal and nuclear power plants.

According to U.S. Department of Energy, a

network of wind farms in just four states could

meet all U.S. electricity means.

Fuel-Cell Vehicles

Fuel-efficient vehicles powered by a fuel

cell that runs on hydrogen gas are being

developed.

Combines hydrogen gas (H2) and oxygen

gas (O2) fuel to produce electricity and

water vapor (2H2+O2 2H2O).

Emits no air pollution or CO2 if the

hydrogen is produced from renewable-

energy sources.

Fig. 17-8, p. 390

Body attachments

Mechanical locks that secure the

body to the chassis

Air system

management

Universal docking connection

Connects the chassis with the

drive-by-wire system in the body Fuel-cell stack

Converts hydrogen

fuel into electricity Rear crush zone

Absorbs crash energy

Drive-by-wire

system controls

Cabin heating unit

Side-mounted radiators

Release heat generated by the fuel cell,

vehicle electronics, and wheel motors Hydrogen

fuel tanks

Front crush zone

Absorbs crash energy

Electric wheel motors

Provide four-wheel drive;

have built-in brakes

National Appliance Energy Act – 1987; energy efficiency stickers on all appliances

Renewable Energy and Technology Competitiveness Act – 1989; effort to develop renewable energy nationally

Clean Air Act Amendments – 1990; set standards for cities and emissions

Energy Policy Act – 1992; comprehensive effort to find renewable energy resources

Hydrogen Future Act – 1996; develop hydrogen as an energy source

PROBLEM – FEW of these actually provide the money needed to research renewable resources

definition things human use that have a limited supply...

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