Energy

Energy

Non-Renewable and Renewable Resources

Geologic Processes

Huge volumes of heated and molten rack moving around the earth’s interior form massive solid plates that move extremely slowly across the earth’s surface. Tectonic plates: huge rigid plates that are moved

with convection cells or currents by floating on magma or molten rock.

Geologic Processes

The earth is made up of a core, mantle, and crust and is constantly changing as a result of processes taking place on and below its surface.

The earth’s interior consists of: Core: innermost zone with solid inner core and molten

outer core that is extremely hot. Mantle: solid rock with a rigid outer part (asthenosphere)

that is melted pliable rock. Crust: Outermost zone which underlies the continents.

The Earth’s Major Tectonic Plates

The extremely slow movements of these plates cause them to grind into one another at convergent plate boundaries, move apart at divergent plate boundaries and slide past at transform plate boundaries.

Figure 15-4Figure 15-4

Pacific Plate The Pacific plate is off the coast of

California. Lots of volcanoes and earthquakes occur here.

“California will fall into the ocean” idea. It is the largest plate and the location of the

ring of fire.

Pacific Plate Transform –

plates slide next or past each other in opposite directions along a fracture.

California will not fall into the ocean!

Importance Plate movement

adds new land at boundaries, produces mountains, trenches, earthquakes and volcanoes.

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

This requires a change in our lifestyle and some people resist.

Restoration

Definition – recycling our resources EX: aluminum, glass, tin, steel, plastics

Problems – 1. recycling a resource often costs more than

using the raw material2. 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.


Fig. 15-10, p. 344

Natural Capital Degradation

Extracting, Processing, and Using Nonrenewable Mineral and Energy Resources

StepsSteps Environmental effectsEnvironmental 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

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

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

Specific Resources & Their Uses 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

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.


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.

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.)

Open-pit Mining Machines dig

holes and remove ores, sand, gravel, and stone.

Toxic groundwater can accumulate at the bottom.


Area Strip Mining Earth movers strips away overburden, and giant shovels removes mineral deposit.

Often leaves highly erodible hills of rubble called spoil banks.


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.


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.


Solutions: Sustainable Use of Nonrenewable Resources• Do not waste mineral resources. • Recycle and reuse 60–80% of mineral

resources. • Reduce subsidies for mining mineral

resources.• Increase subsidies for recycling, reuse, and

finding less environmentally harmful substitutes.

• Slow population growth.

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

Why Primary to Secondary

We use the fuel to heat the water to make the steam to turn the turbine to power the generator that produces the electricity we use!

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!!!

Examples of Primary Sources

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

only 2.9% of the world’s proven oil reserves.

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

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 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.

How Long Will the Oil Party Last?

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


NATURAL GAS Natural gas, consisting mostly of methane,

is often found above reservoirs of crude oil.

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.

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.

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.

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

Renewable Resources and Electricity

The European Union aims 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.

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)

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 but this is changing!

Producing Electricity with Solar Cells

Solar cells can be used in rural villages with ample sunlight who are not connected to an electrical grid.


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.

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.


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.

PRODUCING ELECTRICITY FROM WIND

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


PRODUCING ELECTRICITY 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; includes producing biofuels; 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

The scarcity of fuelwood causes people to make fuel briquettes from cow dung in India. This deprives soil of plant nutrients.


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.

Producing Ethanol Crops such as

sugarcane, corn, and switchgrass as well as agricultural, forestry and municipal wastes can be converted to ethanol.

Switchgrass can remove CO2 from the troposphere and store it in the soil.


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.

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.

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

PRODUCING ELECTRICITY 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.

Geothermal

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

This is the only energy source that doesn’t originate 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.

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

PRODUCING ELECTRICITY 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 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. It also produces a ton of thermal pollution!

NUCLEAR ENERGY When isotopes of uranium and plutonium

undergo controlled nuclear fission, the resulting heat produces steam that spins turbines to generate electricity.

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.


NUCLEAR ENERGY

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


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.

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.


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.

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.

WAYS TO IMPROVE ENERGY EFFICIENCY We can save energy in new buildings by using

solar power, super-insulating buildings, 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.


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.


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.


Definition Any fuel that meets certain

emissions standards; they give off low amounts of pollution

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 technologyReformulated 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 compound. It takes energy and money to produce it (net

energy is low). Fuel cells are expensive.

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

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