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Need Energy? Why Not Shoot for the Moon?

The Moon as a Source for Nuclear Fusion and Tidal Generation

Kenneth O’Rourke MISEP II August 2008

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Table of contents 1) Overview --------------------------------------------------------------------------------------- 3 2) Content ---------------------------------------------------------------------------------------- 5

a) Introduction ------------------------------------------------------------------------------- 5 b) Mechanical energy ---------------------------------------------------------------------- 6 c) Nuclear energy --------------------------------------------------------------------------- 7

i) Fission ------------------------------------------------------------------------------- 8 ii) Fusion --------------------------------------------------------------------------------- 9

d) Moon ------------------------------------------------------------------------------------ 16 i) Geology ------------------------------------------------------------------------------ 16 ii) Tides --------------------------------------------------------------------------------- 17

(1) Tidal barrage ------------------------------------------------------------------- 19 (2) Tidal lagoons ------------------------------------------------------------------ 23 (3) Tidal energy is like wind energy --------------------------------------------- 24

e) References ------------------------------------------------------------------------------- 26 3) Pedagogy ------------------------------------------------------------------------------------- 30

a) Unit description ------------------------------------------------------------------------- 31 b) Misconceptions --------------------------------------------------------------------------- 31 c) Understanding by design ---------------------------------------------------------------- 33

i) Stage one: Identifying Desired Results ------------------------------------------- 33 (1) Enduring understandings, Essential questions, Learning outcomes ----- 34 (2) Standards ------------------------------------------------------------------------- 35 (3) Unit objectives ------------------------------------------------------------------ 37

ii) Stage two: Assessment Evidence -------------------------------------------------- 37 iii) Stage three: The Learning Plan --------------------------------------------------- 39

(1) Lesson five: Fully developed lesson ------------------------------------------ 42 iv) Resources ---------------------------------------------------------------------------- 47 v) Appendix ------------------------------------------------------------------------------ 48 vi) References ---------------------------------------------------------------------------- 57

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Overview

I have always been drawn to figure out why and how things worked. This naturally led

me into a love of science. How does the universe work is the ultimate question. In order

to begin to understand how and why everything works the way it does, energy is the most

important topic be investigated. Energy is the common thread that ties all of the physical

sciences together. I am still amazed at the beauty of Newton’s Laws and the Law of

Conservation of Energy. No matter how many times I teach or read about them, I am

stunned at their sublime beauty. My amazement only grew when I investigated

Einstein’s Theories of Special Relativity and General Relativity. This feeling of awe and

appreciation of science is one attribute I wish to pass on to my students. Even though the

content piece of this project is on energy, it was first germinated in the Earth and Space

rotation of this program. I remember sitting in class learning about the tides in Jane

Dmochowski’s class and thinking about the immense amounts of energy that it takes to

move oceans. I knew that the energy was there for the taking, if we could find an

economical way of harnessing it. As I researched a little deeper into tidal power and

other sources of alternative energy, I came across an article by Harrison Schmidt. He

was the second to last human, and the only geologist to walk on the Moon. The article

detailed that the Moon could be mined for helium-3 for nuclear fusion reactors. I began

thinking that meeting the energy needs of the future could be intimately tied to the Moon,

and my capstone topic was born.

The content section of this project details why and how the Moon could help meet the

energy needs of the world. It starts with a discussion of the basics of how power from

nuclear sources operates. It details why and how the Moon is a potential source for clean

and environmentally friendly nuclear fusion. (It is estimated that one shuttle full of

helium-3 would be enough to meet the United State’s energy needs for a full year. If that

sounds exciting, be sure to read on!) It then details how the energy from the tides can

and is being used to bring clean energy to the public.

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The pedagogy section of this project focuses on alternative energy with the students

being guided into considering the Moon as a source for alternate gravitational energy and

a source of fuel for nuclear fusion. By introducing my students to this fascinating topic

that has real implications to the world today, I believe that the awe and wonder I feel will

be transmitted to my students. Much of nuclear physics content is significantly above the

grade level of my students, but a basic understanding of the reactions and how the

reactors work is not. The pedagogy piece of this project is focused on higher order

thinking skills of analysis and synthesis of energy in general, and not on a detailed

understanding of nuclear physics. Students will need to evaluate the information to come

up with logical solutions for meeting our future energy needs.

Acknowledgements:

I would like to thank Dr. Barbara Riebling and Dr. Jane Dmochowski of the University of

Pennsylvania and Kathleen Tait of the J. R. Masterman Laboratory and Demonstration

School for all of their contributions, dedication, and patience to this paper. I would also

like to thank my family for their unwavering support through the program. I have been

enthralled, excited, and motivated by all of the instructors in the MISEP program, and

they have inspired me to learn all I could. I humbly thank you all and I aspire to someday

reach your level of knowledge and wisdom.

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Content Section

Need Energy? Why not shoot for the Moon?: The Moon as a source for

nuclear fusion and tidal generation.

Introduction

Energy: What is it, and why don’t we have enough

Energy in its simplest definition is the ability to do work. What exactly is “work”? Work

is the application of force over a distance. The resulting unit for energy is the joule,

which is equal to kgm2/s2. The more energy you have, the larger the force you can apply

or a larger distance you can apply a smaller force. The Law of Conservation of Energy

states that energy cannot be created or destroyed, but energy is changed from one form

into another. The energy problem that the world faces is not that there is not enough

energy, but that it is difficult to harness into useful energy for human consumption.

Other than the chemical energy from food used to maintain homeostasis, the dominant

forms of energy that humans use are electrical energy and chemical energy, in the form of

fossil fuels in the combustion engine and combustion for heat. Electrical energy can also

be used to generate heat and propel machines. Even though electrical energy is widely

used, it is not a resource and must be converted from other sources of energy. The main

source for electricity generation is fossil fuels, a nonrenewable resource.

We need to develop energy supplies that will meet the needs of an ever-growing world

population. For the purposes of this paper the two forms of energy most relevant are

mechanical energy and nuclear energy. (One of the most effective ways to harness these

forms of energy into a usable form is through electricity generation.) The Moon may be

an abundant source for both forms. The enormous amount of energy stored in the

movement of the tides can be transformed into electrical energy with no greenhouse gas

emissions, and the surface of the Moon may be the most promising source for mining

helium-3, a nuclear fuel that may make nuclear fusion generators a reality.

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How many gallons of water can an average person lift? The more gallons lifted, the more

energy expended to lift them. Expand this idea to how much energy is involved in

moving the oceans and one realizes the enormous energy potential of our oceans. The

gravitational attraction between the Earth and the Moon is the engine that drives the tides,

making them an extremely predictable source of energy. The question is how to

transform the energy stored in the oceans into usable energy.

Since the 1950’s, scientists have hailed nuclear fusion reactors as the cure for our energy

needs: a source of energy with no adverse environmental side effects. Still it is not a

reality. To date no viable, sustainable nuclear fusion reactor has been developed. Some

of the latest research shows that nuclear fusion would be practical and sustainable if we

had enough of a certain isotope of helium, helium-3. Most of the research has focused on

hydrogen fusion, but a certain level of radiation and an abundance of neutrons are

produced. The neutrons are problematic in they are hard to contain and are destructive to

the walls of the reactors. The benefit of 3He is that neutron emissions are low and no

harmful radiation is produced. The problem is that helium-3 is not found in any

abundance on the Earth. The Moon on the other hand is an abundant source for this

nuclear fuel, just as it is the source for moving the tides. One of the paths to energy

independence might be through the Moon. By converting the energy of the moon stored

in the tides, and mining helium-3 on the Moon to fuel nuclear fusion reactors, the Earth’s

energy needs could be met without many of the current harmful effects.

Mechanical Energy

Mechanical energy can be separated into two forms: Potential energy and kinetic energy.

They are two sides of the same coin. Potential energy is stored energy or the energy of

position and kinetic energy is the energy of motion. With regard to mechanical energy,

when potential energy decreases, kinetic energy increases by an equal amount. One of

the best applications of potential to kinetic energy transformations comes from the

transformation of gravitational potential energy into kinetic energy. A rock at a height

has potential energy. As it falls, it loses potential energy and gains an equal amount of

kinetic energy. This gravitational potential energy is harnessed when the potential energy

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of falling water is converted into the kinetic energy of the running water force a wheel to

turn (a water wheel). That turning wheel when connected to large coils of wire in a

magnetic field produces electrical energy. The kinetic energy of the tides ebbing and

flowing can be transformed into electrical energy in a similar way.

Nuclear Energy

Nuclear energy can also be separated into 2 separate forms: nuclear fission and nuclear

fusion. Nuclear fusion is the splitting of large atomic nuclei into smaller elements

releasing energy, and nuclear fusion is the joining of two small atomic nuclei into a larger

element and in the process releasing energy. The mass of a nucleus is always less than

the sum of the individual masses of the protons and neutrons which constitute it. The

difference is a measure of the nuclear binding energy which holds the nucleus together

(Figure 1). As figures 1 and 2 below show, the energy yield from nuclear fusion is much

greater than nuclear fission.

Figure 1

Nuclear binding energy = ∆mc2

For the alpha particle ∆m= 0.0304 u which gives a binding energy of 28.3 MeV.

(Figure from: http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/nucbin.html)

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Fission and fusion can yield energy

Figure 2

(Figure from: http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/nucbin.html)

Nuclear fission

When a neutron is fired at a uranium-235 nucleus, the nucleus captures the neutron. It

then splits into two lighter elements and throws off two or three new neutrons (the

number of ejected neutrons depends on how the U-235 atom happens to split). The two

new atoms then emit gamma radiation as they settle into their new states. (John R.

Huizenga, "Nuclear fission", in AccessScience@McGraw-Hill,

http://proxy.library.upenn.edu:3725) There are three things about this induced fission

process that make it especially interesting:

1) The probability of a U-235 atom capturing a neutron as it passes by is fairly

high. In a reactor working properly (known as the critical state), one neutron

ejected from each fission causes another fission to occur. (Huizenga)

2) The process of capturing the neutron and splitting happens very quickly, on the

order of picoseconds (1x10-12 seconds). (Huizenga)

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3) An incredible amount of energy is released, in the form of heat and gamma

radiation, when a single atom splits. The two atoms that result from the fission

later release beta radiation and gamma radiation of their own as well. The

energy released by a single fission comes from the fact that the fission

products and the neutrons, together, weigh less than the original U-235 atom.

The difference in weight is converted directly to energy at a rate governed by

the equation E = mc2. Something on the order of 200 MeV (million electron

volts) is released by the decay of one U-235 atom.1That may not seem like

much, but there are a lot of uranium atoms in a pound of uranium. A pound of

highly enriched uranium used to power a nuclear submarine is on the order of

a million gallons of gasoline. (Huizenga)

There are some drawbacks of nuclear fission reactors, namely:

1) Mining and purifying uranium has, historically, been a process that leaves very

toxic byproducts.

2) Improperly functioning nuclear power plants can create big problems. The

Chernobyl disaster is a good recent example that dramatically shows the worst-

case scenario. Chernobyl scattered tons of radioactive dust into the

atmosphere.

3) Spent fuel from nuclear power plants is toxic for centuries, and, as yet, there is

no safe, permanent storage facility for it. Yucca mountain in Nevada is the

future permenant depository when it becomes operational.

4) Transporting nuclear fuel to and from nuclear plants poses some risk, although

to date, the safety record in the United States has been good.

Nuclear Fusion

The sun releases energy through nuclear fusion reactions. The immense temperature and

pressure in the Sun forces hydrogen atoms fuse into deuterium, then the deuterium atom

fuses together with another hydrogen atom to form a tritium atom, and then the tritium

1 1 eV is equal to 1.602 x 10-12 ergs, 1 x 107 ergs is equal to 1 joule, 1 joule equals 1 watt-second, and 1 BTU equals 1,055 joules).

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atom fuses with another hydrogen atom to from a helium atom. The resulting helium

atom’s mass is less than four hydrogen atoms. The missing mass is transformed into

energy by Einstein’s E=mc2 equation (Figures 1 and 2). The reaction between the nuclei

of the two heavy forms (isotopes) of hydrogen - deuterium (D) and tritium releases 17.6

MeV (2.8 x 1012 joule).

There are currently two types of fusion reactions that are considered the most promising

for nuclear fusion reactors: the deuterium tritium reactor, and the helium-3 deuterium

reactor.

Deuterium tritium reaction

The fusion of deuterium and tritium reaction yields 17.6 MeV of energy but requires a

temperature of approximately 40 million Kelvin to overcome the coulomb barrier and

ignite it. (Post et al., 2005)

Even though a lot of energy is required to overcome the Coulomb barrier and initiate

hydrogen fusion, the energy yields are enough to encourage continued research.

Hydrogen fusion on the earth could make use of the reactions:

(Post et al., 2005)

These reactions are more promising than the proton-proton fusion of the stars for

potential energy sources. Of these the deuterium-tritium fusion appears to be the most

promising and has been the subject of most experiments. In a deuterium-deuterium

reactor, another reaction could also occur, creating a deuterium cycle:

(Post et al., 2005)

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This reaction also releases a neutron. This neutron is difficult to contain due to its non-

polar nature. As a result the walls of the reactor suffer significant damage over a short

time from a constant barrage of neutrons. Current research is continuing in an effort to

contain the neutrons without sustaining reactor damage. (Post et al., 2005)

Helium-3 deuterium reaction

The Major advantages of 3He- deuterium reactions are: 1. a significant reduction of

radiation damage in the form of neutrons to the reactor wall, 2. reduction of avoidance of

radioactivity, 3. higher energy conversion without waste heat (Kolinsky, 2001).

However, there are still some problems. The reactors need to operate at higher

temperatures than deuterium- tritium reactions, and there is a very limited source of

helium-3 on the surface of the Earth. Helium-3 is a natural part of the solar wind. Our

atmosphere does not allow helium-3 to reach the surface, but the Moon has no

atmosphere and is constantly bombarded by helium-3. (Kolinsky, 2001).

The deuterium and helium-3 atoms come together to give off a proton and helium-4. The

products weigh less than the initial components; the missing mass is converted to energy.

1 kg of helium-3 burned with 0.67 kg of deuterium gives us about 19 megawatt-years of

energy output. The fusion reaction time for the D-3He reaction becomes significant at a

temperature of about 10 KeV, and peaks about about 200 KeV. A 100 KeV reactor

appears to be optimum. (University of Wisconsin, Fusion Technology institute,

http://fti.neep.wisc.edu/presentations/lae_dhe3_icenes07.pdf) A reactor built to use the

D-3He reaction would be inherently safe. The worst-case failure scenario would not

result in any civilian fatalities or significant exposures to radiation. (Kolinsky, 2001).

Inertial Electrostatic Confinement (IEC) and toroidal magnetic field for confining a

plasma (Tokamak)

There are currently 2 methods in which helium-3 has been shown to fuse in a reactor.

One is a high pressure (gravity, and inertial confinement) and high temperature

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(electrostatic confinement and magnetic confinement) reactor. At the Fusion Technology

institute at the University of Wisconsin-Madison they have developed an Inertial

electrostatic containment device that is the first known fusion of helium-3 with deuterium

on a steady state basis. (Radel, Kulcinsky, Donavan, Detection of HEU Using a Pulsed

D-D Fusion Source, March 2007)

Photo of IEC in action (http://iec.neep.wisc.edu)

The gridded IEC approach possesses the advantage that ions can be continuously

accelerated to high fusion relevant energy with relative ease (tens of KeV). The steady

state burning of advanced fusion fuels such as deuterium- 3He and 3He-3He is a key

feature of IEC devices. The IEC device does not require any magnetic coils for plasma

confinement, allowing it to be lightweight and portable. Since the reaction does not

utilize deuterium- tritium the problem of neutron activation of the reactor is of far less

significance. The device is small. It is an approximately one meter in diameter

aluminum vacuum cylinder that is 65 cm high. (Radel, Kulcinsky, Donavan, Detection

of HEU Using a Pulsed D-D Fusion Source, March 2007)

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(photo from: http://fti.neep.wisc.edu/ncoe?rm=iec)

(photo from: http://iec.neep.wisc.edu/photopages/GeneralOpPics.htm)

The device produced a steady stream of protons, neutrons, helium-4, tritium, gamma and

x rays. (Radel, Kulcinsky, Donavan, Detection of HEU Using a Pulsed D-D Fusion

Source, March 2007)

Fusion fuel cycles, except He-3-He-3, are not completely aneutronic due to their side

reactions. Neutron wall loadings can be kept low (by orders of magnitude) compared to

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D-T fuelled plants with the same output power, eliminating the need for a breeding

blanket 2and the replacement of the first wall and shielding components during the entire

plant lifetime. The availability of He-3 and the attainment of the higher plasma

parameters required for burning are challenging problems for the D-He-3 fuel cycle.

High beta and/or high field innovative confinement concepts, such as the field-reversed

configuration and, to a lesser extent, the TOKAMAKks are suitable devices for advanced

fuel cycles. In the early 1990s, the ARIES-III D-He-3 TOKAMAK was developed within

the framework of the ARIES study. (The ARIES program is a national, multi-institutional

research activity. (Guebal et al, 2007).

(ARIES III TOKAMAK from: http://fti.neep.wisc.edu/ncoe?rm=dhe3)

Its mission is to perform advanced integrated design studies of the long-term fusion

energy embodiments to identify key research and development directions and to provide

visions for the fusion program. It is funded by the Office of Fusion Energy Sciences,

U.S. Department of Energy.) The UW D-He-3 Apollo series, along with ARIES-III,

demonstrated attractive safety characteristics, including low activity and decay heat

levels, low-level waste, and low releasable radioactive inventory from credible accidents.

Another advantage for the D-He-3 system is the possibility of obtaining electrical power

by direct energy conversion of the protons and radiation produced by fusion reactions.

2 Protect the magnets and the vacuum vessel from neutron and gamma radiation, produce the tritium necessary for continued fusion reactions,

convert neutron energy into heat and evacuate it to generate a cycle capable of supplying electricity.

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The nuclear fusion reaction can only be self-sustaining if the rate of loss of energy from

the reacting fuel is not greater than the rate of energy generation by fusion reactions. The

simplest consequence of this fact is that there will exist critical or ideal ignition

temperatures below which a reaction could not sustain itself, even under idealized

conditions. In a fusion reactor, ideal or minimum critical temperatures are determined by

the unavoidable escape of radiation from the plasma. A minimum value for the radiation

emitted from any plasma is that emitted by a pure hydrogenic plasma in the form of x-

rays or bremsstrahlung. (Charged particles moving through matter will lose energy by

emitting a photon, or interacting with the matter causing it to lose energy.) Thus plasmas

composed only of isotopes of hydrogen and their one-for-one accompanying electrons

might be expected to possess the lowest ideal ignition temperatures. In fact, it can be

shown by comparison of the nuclear energy release rates with the radiation losses that the

critical temperature for the D-T reaction is about 4 × 107 K. For the D-D reaction it is

about 10 times higher. Since both radiation rate and nuclear power vary with the square

of the particle density, these critical temperatures are independent of density over the

density ranges of interest. The concept of the critical temperature is a highly idealized

one, since in any real cases additional losses must be expected to occur which will

modify the situation, increasing the required temperature. (Richard F. Post, Allen H.

Boozer, Eric Storm, Bogdan Maglich, James S. Cohen, "Nuclear fusion", in

AccessScience@McGraw-Hill, http://proxy.library.upenn.edu:3725, DOI 10.1036/1097-

8542.458800)

The absence of neutrons and radioactivity removes the need for shielding. This is

particularly significant for aero-space applications, since the weight of shielding in a

(Post et al., 2005)

An aneutronic reactor 3 also offers the advantages of non-radioactive fuel and non-

radioactive waste. Since all nuclear energy released in aneutronic reactions is carried by

3 Aneutronic fusion is any form of fusion power where no more than 1% of the total energy released is carried by neutrons.

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charged particles, if these particles could be directed into a beam a flow of electric charge

would result, and nuclear energy could be converted directly into electrical energy, with

no waste heat. (B. Maglich and J. Norwood (eds.), Proceedings of the 1st International

Symposium on Feasibility of Aneutronic Power, Nucl. Instrum. Meth., A271:1–240,

1988)

An aneutronic reactor could be small, producing 1–100 MW of electric power, and mass

production might be possible. Aneutronic reactors cannot breed plutonium for nuclear

weapons. (B. Maglich and J. Norwood (eds.), Proceedings of the 1st International

Symposium on Feasibility of Aneutronic Power, Nucl. Instrum. Meth., A271:1–240,

1988)

The only practical source for helium-3 and a viable commercial aneutronic reactor is the

Moon.

Moon

To understand how the Moon factors into the energy sources discussed in the previous

section, one must first understand the Moon’s geology.

Geology

The lunar landings gave scientists the opprotunity to directly test rocks from the Moon.

Engineers at the University of Wisconsin predicted that Lunar samples should contain

helium-3 as a result of interaction from the solar wind. Lunar samples were tested and

were found to contain helium-3 (Schmidt 2004). There is a particularly strong

correlation between helium-3 content and titanium oxide content of the lunar rock

(Wittenberg, Camerson, et al, 2001). Samples collected in 1969 by Neil Armstrong

during the first lunar landing showed that helium-3 concentrations in lunar soil are at

least 13 parts per billion (ppb) by weight. Levels may range from 20 to 30 ppb in

undisturbed soils. The Moon contains vast stores of helium-3, locked up most efficiently

in deposits of titanium. The titanium containing rocks found on the Moon's surface, acts

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like a sponge, soaking up the particles of helium-3 driven through space by the solar

wind. The solar wind cannot deposit helium-3 on the Earth, since the Earth’s atmosphere

protects the surface from solar wind. During the 4 billion years since the Moon was

formed, the titanium reserves have absorbed around a million tonns of helium-3. Almost

all of it is in the top 3 metres of soil in low-lying areas on the near side of the Moon.

(Sviatoslavsky, I. N., Processes and Energy Costs for Mining lunar Helium-3, Wisconsin

Univ., Madison, In NASA, Lewis Research Center, Lunar Helium-3 and Fusion Power p

129-146 (SEE N89-14842 06-75) Because the concentration of helium-3 in the rocks is

relatively low compared to the mass of the rock, if lunar rock were to be used as a source

of energy for nuclear reactors on Earth, it would be necessary to process large amounts of

rock and soil to isolate the material. Digging a patch of lunar surface roughly three-

quarters of a square mile to a depth of about 9 ft. should yield about 220 pounds of

helium-3 (Schmidt 2004). In 1986, John Santarius, a physicist at the University of

Wisconsin- Madison, proposed mining the titanium-rich soil with a robotic digger and

removing the helium-3 by heating it to 700 degrees C with the Sun's rays focused by an

orbiting mirror. At this temperature, more than 85 per cent of the helium-3 would boil

off along with other gases such as oxygen, hydrogen, nitrogen and carbon dioxide. These

could be separated by cooling the mixture until only helium remained a gas, a process

that would be relatively easy during the lunar night when temperatures plummet to -100

degrees C. While the other gases might prove useful for human colonists, the helium

could be transported to Earth. It is estimated that eventually the cost of lunar fusion fuel

would fall as low as $100,000 per kilogram - the US currently charges $700,000 for the

same amount of its helium-3 (Sviatoslavsky)

The prospects for Helium-3 are very promising, but will do little to help in the next few

years. But the Moon can be a major contributor to our energy crisis solutions in the near

term as well.

Earth’s Gravitational Attraction to the Moon and the Resulting Tides

The revolution and rotation of the Moon are well understood and there is little debate as

to their mechanisms in the present day. However, it is generally unknown to the public

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that the Moon is responsible for the current length of our day. Research in the early part

of the 20th century found that the Moon was much closer in the past and is getting farther

everyday (Street, 1917). More current investigations found the Moon to have a drag

effect on the Earth, causing our days to go from 18 hours long to the current 24 hours.

While the Moon orbits the Earth, it will continue to lengthen our days (Brosche, 1984).

There is also evidence that if it were not for the Moon, the Earth’s tilt would be much

more variable (one model suggests it would change from eleven to forty degrees)

(Peterson, 1993). This would have had a tremendous impact for life on Earth. With the

Earth’s tilt varying, the Earth’s climate would be much more erratic, making it difficult

for more complex life forms to develop.

The biggest influence that the Moon has on the Earth on a daily basis is the tides. This

interaction has been understood on a gross scale according to Newton’s laws for a very

long time (Schneider, 1880). The Sun also plays a role in the Earth’s tides. Although the

Sun is much larger than the Moon, it is also much further away. The importance of

distance becomes obvious when you examine Newton’s law of universal gravitation. The

strength of gravity decreases with the square of the distance proportional to the product of

the two masses. A more sophisticated description of how the Moon influences the tides

involves a gravitational gradient. (Trujillo, Thurman, Essentials of Oceanography,

Pearson Prentice Hall, 2005) Because the Moon is much closer the gravitational gradient

between the far and near side of the moon is more significant than the gradient between

the near and far side of the sun. This results in the lunar force being inversely

proportional to the cube of the distance, thereby causing the Moon to have a greater

influence on the tides on Earth. The Sun’s influence is felt as constructive or destructive

to the Moon’s influence based on the geometrical relationship between the forces of the

Earth, Moon, Sun system. When the geometrical relationship is parallel, as in the Full

Moon and New Moon, the forces are additative and the Earth has the highest tides. When

the geographical relationship is at right angles between the Sun and the Moon, The Sun’s

influence mitigates the Moon’s influence and the tides are at their lowest. (Trujillo,

Thurman, Essentials of Oceanography, Pearson Prentice Hall, 2005)

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The Moon pulls on Earth’s ocean nearest the Moon and causes a bulge. On the opposite

side of the Earth, the bulge is caused by the moon pulling on the Earth’s center of mass

more than it pulls the ocean on the opposite side of the Earth, essentially resulting in the

Earth being pulled out from under the water and creating a second high tide each day.

Some of the other factors that influence the tides are the shapes of the coastline, depth of

the water, and the deformation of the ocean basin (Farrel, 1973). These effects are

demonstrated by the unusually large tidal range in the Bay of Fundy. The effects of the

Moon on the tides is not only on seas and oceans, but on groundwater as well; studies on

groundwater over the course of months show that the average groundwater levels also

fluctuate with the tides (Schureman, 1926).

How is tidal energy harnessed?

There are two different approaches to the exploitation of tidal energy. The first is to

harness the cyclic rise and fall of the sea level through entrainment and the second is to

harness local tidal currents in a manner somewhat analogous to wind power.

Tidal Barrage Methods

There are many places in the world in which local geography results in particularly large

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tidal ranges. Sites of particular interest include the Bay of Fundy in Canada, which has a

mean tidal range of 10 m, the Severn Estuary between England and Wales, with a mean

tidal range of 8 m and Northern France with a mean range of 7 m. A tidal-barrage power

plant has been operating at La Rance in Brittany since 1966 (Banal and Bichon, 1981).

This plant, which is capable of generating 240 MW, incorporates a road crossing of the

estuary. It has recently undergone a major ten-year refurbishment program

.

Photos and diagrams from: http://www.reuk.co.uk/Severn-Barrage-Tidal-Power.htm

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Other operational barrage sites are at Annapolis Royal in Nova Scotia (18 MW), the Bay

of Kislaya, near Murmansk (400 kW) and at Jangxia Creek in the East China Sea (500

kW) (Boyle, 1996). Schemes have been proposed for the Bay of Fundy and for the

Severn Estuary but have never been built.

Principles of Operation.

On a fundamental level, the principles of operation are always the same. An estuary or

bay with a large natural tidal range is identified and then artificially enclosed with a

barrier. This would typically also provide a road or rail crossing of the gap in order to

maximise the economic benefit. The electrical energy is produced by allowing water to

flow from one side of the barrage, through low-head turbines, to generate electricity.

There are a variety of suggested modes of operation. These can be broken down initially

into single-basin schemes and multiple-basin schemes. The simplest of these are the

single-basin schemes.

Single-Basin Tidal Barrage Schemes

These schemes require a single barrage across the estuary. There are three different

methods of generating electricity with a single basin. All of the options involve a

combination of sluices which, when open, can allow water to flow relatively freely

through the barrage, and gated turbines, the gates of which can be opened to allow water

to flow through the turbines to generate electricity. (Survey of Energy Resources, World

Energy Council, Harnessing the Energy in Tides, 2007)

Ebb Generation Mode

During the flood tide, incoming water is allowed to flow freely through sluices in the

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barrage. At high tide, the sluices are closed and water retained behind the barrage. When

the water outside the barrage has fallen sufficiently to establish a substantial head

between the basin and the open water, the basin water is allowed to flow out though low-

head turbines and to generate electricity.

The system can be considered as a series of phases. Typically the water will only be

allowed to flow through the turbines once the head is approximately half the tidal range.

This method will generate electricity for, at most, 40% of the tidal range. (Survey of

Energy Resources, World Energy Council, Harnessing the Energy in Tides, 2007)

Flood Generation Mode

The sluices and turbine gates are kept closed during the flood tide to allow the water level

to build up outside the barrage. As with ebb generation, once a sufficient head has been

established the turbine gates are opened and water can flow into the basin, generating

electricity. This approach is generally viewed as less favourable than the ebb method, as

keeping a tidal basin at low tide for extended periods could have detrimental effects on

the environment and on shipping. In addition, the energy produced would be less, as the

surface area of a basin would be larger at high tide than at low tide, which would result in

rapid reductions in the head during the early stages in the generating cycle. (Survey of

Energy Resources, World Energy Council, Harnessing the Energy in Tides, 2007)

Two-Way Generation

It is possible, in principle, to generate electricity during both ebb and flood currents.

Computer models do not indicate that there would be a major increase in the energy

production. In addition, there would be additional expenses associated in having a

requirement for either two-way turbines or a double set to handle the two-way flow.

Advantages include, however, a reduced period with no generation and the peak power

would be lower, allowing a reduction in the cost of the generators. (Survey of Energy

Resources, World Energy Council, Harnessing the Energy in Tides, 2007)

23

Double-Basin Systems

All single-basin systems suffer from the disadvantage that they only deliver energy

during part of the tidal cycle and cannot adjust their delivery period to match the

requirements of consumers. Double-basin systems have been proposed to allow an

element of storage and to give time control over power output levels. The main basin

would behave essentially like an ebb generation single-basin system. A proportion of the

electricity generated during the ebb phase would be used to pump water to and from the

second basin to ensure that there would always be a generation capability.

It is anticipated that multiple-basin systems are unlikely to become popular, as the

efficiency of low-head turbines is likely to be too low to enable effective economic

storage of energy. The overall efficiency of such low-head storage, in terms of energy

out and energy in, is unlikely to exceed 30%. It is more likely that conventional pumped-

storage systems will be utilized. The overall efficiency of these systems can exceed 70%

which is likely to prove more financially attractive. (Survey of Energy Resources, World

Energy Council, Harnessing the Energy in Tides, 2007)

Tidal lagoons

Tidal barrage systems are likely to cause substantial environmental change; ebb

generation results in estuarial tidal flats being covered longer than in a natural estuary.

Electricity would be generated using sluices and gated turbines in the same manner as

conventional' barrage schemes. The principal advantage of a tidal lagoon is that the

coastline, including the intertidal zone, would be largely unaffected. Careful design of the

lagoon could also ensure that shipping routes would be unaffected. A much longer

barrage would, however, be required for the same surface area of entrainment. Some

preliminary studies do suggest that in suitable locations, the costs might be competitive

with other sources of renewable energy. There has not yet been any in-depth, peer-

24

reviewed assessment of the tidal lagoon concept, so estimates of economics, energy

potential and environmental impact should be treated with caution

In 2000 a large vertical-axis floating device (the Enermar project

[www.pontediarchimede.com]) was tested in the Strait of Messina between Sicily and the

Italian mainland. Marine Current Turbines Ltd (www.marineturbines.com) of Bristol,

England, has been demonstrating a large pillar-mounted prototype system called Seaflow

in the Bristol Channel between England and Wales. It is intended that the same company

will install a further large prototype system, SeaGen, in Strangford Narrows in Northern

Ireland, probably in late-summer 2007. Although conceptually similar to Seaflow, it

would be equipped with two rotors and have a rated capacity of 1.2MW.

In Norway, the Hammerfest Strøm system (www.tidevannsenergi.com) demonstrated that

pillar-mounted horizontal-axis systems can operate in a fjord environment. In the USA

the first of an array of tidal turbines were installed in December 2006 in New York's East

River (www.verdantpower.com ). Once fully operational this should be the world's first

installed array of tidal devices.

In 2007, The European Marine Energy Centre (EMEC) (www.emec.org.uk), which was

established in 2004 to allow the testing of full-scale marine energy technology in a robust

and transparent manner, became fully equipped for the testing of tidal, as well as wave

energy, technology. The tidal test berths are located off the south-western tip of the

island of Eday, in an area known as the Fall of Warness.

The facility offers five tidal test berths at depths ranging from 25 m to 50 m in an area 2

km across and approximately 3.5 km in length. Each berth has a dedicated cable

connecting back to the local grid. The first tidal device (www.openhydro.com) was

installed at the end of 2006. This is operated by the OpenHydro Group and is a novel

annular-turbine system held by twin vertical pillars.

Tidal power is like wind power

25

The physics of the conversion of energy from tidal currents is superficially very similar to

the conversion of kinetic energy in the wind. Many of the proposed devices have

therefore an inevitable resemblance to wind turbines. There is no total agreement on the

form and geometry of the conversion technology itself. Wind-power systems are almost

entirely horizontal-axis rotating turbines. In these systems the axis of rotation is parallel

to the direction of the current flow. Many developers favour this geometry for tidal

conversion. Vertical-axis systems, in which the axis of rotation is perpendicular to the

direction of current flow, have not been rejected. It is of interest to note that Enermar

used a novel Kobold vertical-axis turbine.

The environmental drag forces on any tidal-current energy-conversion system are very

large, when compared with wind turbines of the same capacity. This poses additional

challenges to the designer. Designs exist for devices which are rigidly attached to the

seabed or are suspended from floating barges, such as the early Loch Linnhe device. It is

generally accepted that fixed systems will be most applicable to shallow-water sites and

moored systems for deep water.

Although prototype tidal-current devices are now available and have mostly proved

successful in their operation, there are still issues requiring resolution before the resource

can be fully exploited. With the exception of the New York East River development,

knowledge of the performance of devices in arrays is somewhat limited, although

theoretical models are at last becoming available. It is also becoming obvious that

turbulence levels in high-energy tidal flows can be considerable. Turbulent amplitudes

exceeding 30% of the time-averaged flows have been measured and this will prove

challenging to systems designers. There is an ongoing need for enhanced understanding

of the behaviour of tidal-current devices in the presence of incident waves. These gaps in

understanding should not prevent ongoing deployment of pre-commercial, or even early-

stage commercial technology, provided that technology developers are aware of the

design constraints that knowledge gaps impose and recognise that they themselves are

part of the research process. This will ultimately allow efficient technology development

and hence allow cost-effective exploitation of the tidal-current resource.

26

Conclusion: If we have the will, the benefits could be out of this world.

Two of the fundamental criteria of an energy solution are that it must be clean and

sustainable. The two methods outlined in this project acomplishes both. The short term

energy crisis can be mitigated through the use of the Moon’s gravitational effect on the

Earth, and the Earth’s long term energy goals can be met utilizing the Moon as a mineral

resource. The energy used to generate the tides is available for human consumption

today, and will be a predictable energy supply as long as the Moon orbits the Earth. We

just need to transform it into useful energy for our needs. The technology is available.

Using it is a matter of will and economics. The Utilization of the Moon as a resource for

helium-3 is not, at present time, feasable. Until He-3 reactors demonstrate a reliable

positive energy gain, the mining operations on the Moon will not happen. The research is

very encouraging and shows significant improvement over the past decade.

References

1) Huizenga, J. R., "Nuclear fission", in AccessScience@McGraw-Hill, (2005)

http://proxy.library.upenn.edu:3725, DOI 10.1036/1097-8542.458400

2) Boozer, A. H., Cohen, J. S., Post, R. F., Maglich, B., Storm, E., "Nuclear

fusion", in AccessScience@McGraw-Hill, (2005)

http://proxy.library.upenn.edu:3725, DOI 10.1036/1097-8542.458800

3) Camerson, E.N. ; Kulcinski, G.L. ; Ott, S.H. ; Santarius, J.F. ; Sviatoslavsky, G.I.

; Sviatoslavsky, I.N. ; Thompson, H.E.; Wittenberg, L.J. (Wisconsin Univ.,

Madison, WI (United States). Fusion Technology Inst.) A review of sup 3 He

resources and acquisition for use as fusion fuel, May, 2001

4) Alderson, E., Ashley, R., Boris, D., Donovan, D., Egle, B., Kulcinski, G., Piefer,

G., Radel, R., Santarius, J., Sorebo, J., Zenobia, S., Detection of HEU Using a

Pulsed D-D Fusion Source, March 2007 [presented at the 2007 ANS Student

Conference, Oregon State University, Corvallis OR, 29-31 March 2007]

27

5) L. El-Guebaly, Henderson, Ibrahim A.,D., Kiedrowski, B.,Sawan, M.,

P.,Slaybaugh, R.,Sviatoslavsky, G., Tautges, T., Wilson, P., and the ARIES

Team, Nuclear Challenges and Progress in Designing Stellarator Power Plants,

June 2007 [presented at the 13th International Conference on Emerging Nuclear

Energy Systems (ICENES 2007), 3-8 June 2007, Istanbul, Turkey]

6) B. Maglich and J. Norwood (eds.), Proceedings of the 1st International

Symposium on Feasibility of Aneutronic Power, Nucl. Instrum. Meth., A271:1–

240, 1988

7) Schmitt, Harrison H. Mining The Moon, Popular Mechanics; Oct2004, Vol. 181

Issue 10, p56-61, 6p, 1 diagram, 3c

8) Sviatoslavsky, I. N., Processes and Energy Costs for Mining lunar Helium-3,

Wisconsin Univ., Madison, In NASA, Lewis Research Center, Lunar Helium-3

and Fusion Power p 129-146 (SEE N89-14842 06-75)

9) Street, R. O. (1917). The Dissipation Energy in the Tides in Connection With the

Acceleration of the Moon’s Mean Motion. Proceedings of the Royal Society of

London. Series A, Containing Papers of a Mathematical and Physical Character,

93 (652) 348-359.

10) Brosche, P., Wolfson, M.M., (1984). Tidal Friction in the Earth-Moon System

[and Discussion]. Philosophical Transactions of the Royal Society of London.

Series A, Mathematical and Physical Sciences, 313 (1524)

11) Peterson, J (1993) Tilted: stable Earth, chaotic Mars - changes in angle of axis

affects climate on planets Science News

http://findarticles.com/p/articles/mi_m1200/is_n9_v143/ai_13533907

12) Schneider, E., (1880). On the Phenomena of the Tides. The Analyst, 7 (5) 154-

157

13) Thurman, H. V., Trujillo, A. P., Essentials of Oceanography, Pearson Prentice

Hall, 2005

28

14) Farrel, W. E. (1973). Earth Tides, Ocean Tides and Tidal Loading. Philosophical

Transactions of the Royal Society of London. Series A, Mathematical and

Physical Sciences, (1239) 253-259.

15) Schureman, P. (1926). Tides in Wells. Geographical Review, 16 (3) 479-483

16) Banal, M. and Bichon A., 1981. Tidal Energy in France, The Rance Tidal Power

Station - some results after 15 years in operation, Proceedings of the Second

International Symposium on Wave and Tidal Energy, Cambridge.

17) Survey of Energy Resources, World Energy Council, Harnessing the Energy in

Tides, 2007

http://www.worldenergy.org/publications/survey_of_energy_resources_2007/tidal

_energy/755.asp

18) Ivich, N., Miley, G.H., Towner, H., Fusion cross sections and reactivities, 1974

Jun 17

19) John P. Holdren, Fusion Energy in Context: Its Fitness for the Long Term.

Science, New Series, Vol. 200, No. 4338 (Apr. 14, 1978), pp. 168-180

20) Ivars Peterson, Sparking Fusion, Science News, Vol. 150, No. 16 (Oct. 19, 1996),

pp. 254-255

21) Michael Guillen, Moon Mines, Space Factories and Colony L5, Science News,

Vol. 110, No. 8 (Aug. 21, 1976), pp. 124-125

22) Kaula, W.M. (1969). The Gravitational Field of the Moon. Science, New Series,

(166) 1581-1588.

23) Brosche, P., Wolfson, M.M., (1984). Tidal Friction in the Earth-Moon System

[and Discussion]. Philosophical Transactions of the Royal Society of London.

Series A, Mathematical and Physical Sciences, 313 (1524)

24) Cameron, E. N., Helium mining on the Moon: Site selection and evaluation, In

NASA. Johnson Space Center, The Second Conference on Lunar Bases and Space

Activities of the 21st Century, Volume 1 p 189-197 (SEE N93-17414 05-91)

29

25) Yoder, C. F., Hutchison, R., (1981). The Free Librations of a dissipative moon

[and Discussion]. Philosophical Transactions of the Royal Society of London.

Series A, Mathematical and Physical Sciences, 303 (1477)

26) Kopal, Z., (1967). The Shape of the Moon, Its Internal Structure and Moments of

Inertia. Proceedings of the Royal Society of London. Series A, Mathematical and

Physical Sciences Vol. 296, No. 1446, (Feb. 7, 1967), pp. 254-265.

27) Street, R. O. (1917). The Dissipation Energy in the Tides in Connection With the

Acceleration of the Moon’s Mean Motion. Proceedings of the Royal Society of

London. Series A, Containing Papers of a Mathematical and Physical Character,

93 (652) 348-359.

28) Lunau, K (2008) Windmills under the sea Maclean’s 121 (16) 46

30

Pedagogy Section

Energy, Energy Everywhere, and Not a Drop to Spare

31

Kenneth O’Rourke Energy Unit

Energy, energy everywhere, and not a drop to spare

Unit Description

This lesson was designed using the backwards design model illustrated by Wiggins and

McTighe (1998) and influenced by the enduring understandings noted below. It covers

the topic of alternative energy generation. The unit is prefaced by a more mechanical

treatment of energy in the previous lesson. The previous lesson focused on potential and

kinetic mechanical energy, energy transformations between them, efficiency of energy

transformations, and the law of conservation of energy. This lesson focuses on higher

order thinking skills that incorporate the concepts learned in the previous lesson and

apply them to the energy crisis facing the world today. Students need to use their

previous knowledge of energy and incorporate it with alternative energy sources.

Students must then use this knowledge to apply it to current problems in society today,

and propose possible solutions. Students will need to analyze and synthesize new and

previous learning to be successful. Students that make a concrete connection between

how the mechanical energy is transformed from or into other forms of energy and then

into something we can use will leave the lesson an informed citizen able to make

intelligent decisions regarding alternative energy in our democratic society.

Student misconceptions (alternate frameworks)

Student misconceptions in science many times occur when an abstract concept is thought

to have concrete properties. This is natural for students to call on their personal

experience with objects and to base their understanding on how they perceive those

objects to behave (Reiner, Slotta et al). The problem also occurs when scientific

language and colloquial language have different meanings, such as the everyday meaning

of theory as an idea to the scientific concept of theory. Research has shown that students

come to school holding powerful conceptions with explanatory power, but those concepts

32

were inconsistent with scientific concepts presented in school (Smith, diSissa, Roschelle).

A common conceptual misconception would be that heavy things fall faster than light

things. While this is true when air resistance becomes significant, it is not an accurate

description of nature. In many cases, I myself have observed these principles as the

biggest roadblocks to students’ understanding of science. In teaching energy some of the

most powerful misconceptions or alternative understandings of energy are: (Clement J.

1987)

� Energy and force are interchangeable terms

� Things use up energy

� Energy is not conserved because we are running out of it

� An object at rest has no energy

� Energy is a thing

� Energy is only associated with movement

� Energy is a fuel

� Energy is recycled

Students that have difficulties in breaking away from vernacular language to using a

more scientific language tend to retard the students’ understanding in science (Jones,

Idol). I have found this to be the case in teaching energy. Students routinely think that

energy, force, momentum, and power, all have the same meaning. While students that

make the distinction usually do much better than students that do not, it is important to

try and insure that all students are brought to the point of understanding the terms unique

scientific meaning. Accentuating the differences and making distinctions in compare and

contrast questions is an effective way to bring students to a proficient understanding of

their scientific meaning. Students come to school with a very powerful preconceived

notion of how the world works. When they are confronted with an anomalous situation,

they will often ignore the anomaly, force it to fit their understanding, or think that they

made a mistake in a lab situation. The successful student will change their model to

incorporate the anomaly. While many students become successful by the time the unit

assessment is completed, many will not retain this changed model into their permanent

33

thinking and will revert back to their previous model (Chong L. 2005) I have seen this in

action myself. Many times I have extinguished the idea that heavy objects fall faster than

light objects in the absence of friction, only to have students explain the opposite to me

within a week of the assessment. An effective method is to constantly revisit those

concepts whenever applicable. For example: when discussing potential energy and

kinetic energy revisit the concepts of acceleration under gravity and make predictions as

to the effects of energy because of the uniform acceleration of all objects on Earth. When

getting to a more complex concept such as energy, previous misconceptions that were

thought to have been extinguished surface again. By using the new topic of energy the

concept of uniform acceleration under gravity can be revisited and the correct concept

reinforced. Students misconceptions through erroneously attributing concrete principles

to abstract concepts, and the misinterpretation of scientific meanings of words, makes it

very challenging to reach many students. A good way to intercept those problems is to

identify them early. One effective method for identifying misconceptions early is the

administering of a pretest. After a student’s misconception has been identified, and as

students work in small groups, I will target those students and attempt to guide them to a

more complete understanding. The final assessment will show what students were

successful in incorporating the new knowledge and amending their previous framework

to get to a more complete understanding of the concept.

Backwards Design Stage one: Identifying desired results

This unit is part of the ninth grade curriculum at Pennfield Middle School. The learning

objectives have been shaped through the Pennsylvania. state standards, the North Penn

School District’s ninth grade science curriculum, the lesson’s enduring understandings,

and the lesson’s essential questions. The unit is comprised of approximately fifteen class

periods lasting 40 minutes each. The assessments are largely a presentation of students’

analysis of information, making a decision based on that analysis, and defending their

analysis through their mastery of the concepts of energy conservation, energy

transformation, the influence of non-conservative forces, and the ability to quantify their

34

argument through mathematics. In order to begin this unit, students must possess

previous knowledge in these areas:

� Define and calculate speed and velocity

� Define and calculate acceleration

� Newton’s Laws of Motion

� Define and calculate force

� Define and calculate momentum

� Define work and solve problems using work

� Define and solve problems using mechanical advantage

� Define Energy

� Calculate kinetic and potential energy problems

� Define and describe the principle of the conservation of energy

Enduring understandings, Essential questions, Learning outcomes

EU #1: Scientific knowledge is continually, although not steadily increasing and

changing through the results of experiments and the bridges built between experimental

observations and underlying concepts and theories.

Q #1: Is nuclear energy a viable energy option?

LO #

1) Students will describe nuclear fusion and nuclear fission

2) Students will compare and contrast nuclear fission and fusion

3) Students will discuss the pros and cons of nuclear fission power generation

4) Students will discuss the problems with designing nuclear fusion reactors

EU #2: Examples of all levels and areas of science are found in daily life and in modern

human development.

Q #2: In what ways will alternative energy generation impact the planet?

35

LO #

5) Students will discuss the importance of alternative fuel sources

6) Students will describe the benefits and disadvantages of solar, wind, tidal, and

geothermal energy

EU #3: There are core concepts and processes in science that transcend the arbitrary

boundaries between traditional disciplines.

Q #3: How is energy described in physics, chemistry, & biology, and how are they

related?

LO #

7) Students will describe how energy is transformed from one form to another within

and without systems

8) Students will describe how energy leaves a system during an energy

transformation through non-conservative forces (friction, heat)

9) Students will explain the implausibility of a perpetual motion machine through

the Law of Conservation of Energy

Standards

3.1. Unifying Themes

3.1.10. GRADE 10

A. Describe concepts of models as a way to predict and understand science and

technology.

• Apply mathematical models to science and technology. (EU #3, Q #3, LO 7, 8, 9)

B. Describe patterns of change in nature, physical and man made systems.

• Describe how fundamental science and technology concepts are used to solve

practical problems (EU #2, Q #2, LO 5 & 6)

• Recognize that stable systems often involve underlying dynamic changes

36

(EU #3, Q #3, LO 7, 8)

3.2. Inquiry and Design

3.2.10. GRADE 10

A. Apply knowledge and understanding about the nature of scientific and technological

knowledge.

• Integrate new information into existing theories and explain implied results.

(EU #1, Q #1, LO 1, 2, 3, 4)

B. Apply process knowledge and organize scientific and technological phenomena in

varied ways.

• Develop appropriate scientific experiments: raising questions, formulating

hypotheses, testing, controlled experiments, recognizing variables, manipulating

variables, interpreting data, and producing solutions.

(EU #1, Q #1, LO 1, 2, 3, 4)

• Use process skills to make inferences and predictions using collected information

and to communicate, using space / time relationships, defining operationally.

(EU #2, Q #2, LO 5 & 6)

C. Apply the elements of scientific inquiry to solve problems.

• Generate questions about objects, organisms and/or events that can be answered

through scientific investigations. (EU #1, Q #1, LO 1, 2, 3, 4)

• Evaluate the appropriateness of questions. (EU #1, Q #1, LO 1, 2, 3, 4)

• Conduct a multiple step experiment. (EU #2, Q #2, LO 5 & 6)

• Suggest additional steps that might be done experimentally.

(EU #1, Q #1, LO 1, 2, 3, 4)

D. Identify and apply the technological design process to solve problems.

• Examine the problem, rank all necessary information and all questions that must be

answered. (EU #1, Q #1, LO 1, 2, 3, 4)

• Propose and analyze a solution.

(EU #1, Q #1, LO 1, 2, 3, 4) (EU #2, Q #2, LO 5 & 6)

• Communicate the process and evaluate and present the impacts of the solution.

(EU #2, Q #2, LO 5 & 6)

3.4 Physical Science, Chemistry and Physics

37

3.4.10. GRADE 10

B. Analyze energy sources and transfers of heat.

• Use knowledge of conservation of energy and momentum to explain common

phenomena (e.g., refrigeration system, rocket propulsion).

(EU #2, Q #2, LO 5 & 6)

Unit Objectives

• Students will discuss the importance of alternative fuel sources

• Students will describe the benefits and disadvantages of solar, wind, tidal, and

geothermal energy

• Students will describe how energy is transformed from one form to another within

systems

• Students will describe how energy leaves a system during an energy

transformation through non-conservative forces (friction, heat)

• Students will describe nuclear fusion and nuclear fission

• Students will compare and contrast nuclear fission and fusion

• Students will discuss the pros and cons of nuclear fission power generation

• Students will discuss the problems with designing nuclear fusion reactors

Backwards design stage two: Assessment evidence

Assessment activity 3:

1) Goal: Students to examine how wind power generation works, and to ascertain its

feasibility in their area.

2) Role: The students act as an engineer designing and testing different materials and

shapes in order to build the most efficient and durable wind generator.

3) Audience: Teacher and peers

4) Situation: Students are given basic plans for a wind generator. The generator and

base is the same for all engineering groups. The students are to draw on previously

learned material to plan their design. The students must test the types of materials,

38

and how to shape those materials to make the best generator. Students then write a

critical analysis of their design and offer ways to improve their design. The

group’s generator that delivers the most current over 3 minutes gets a 5 point bonus

on the assessment 7.

5) Product: A working wind generator, and critical analysis. Worth 8% of the grade

for the unit.

6) Standards:

a) Wind generator graded on output efficiency. 75% to 100% is 20 points, 50% to

74% is 15 points, 25% to 49% is 10 points, 1% to 24 % is 5 points, and 0% is 0

points.

b) Critical analysis needs to explain sources of error, and ways to improve

performance.

Assessment activity 4:

1) Goal: For students to get an appreciation for the amount of energy found in the

tides. For students to examine what types of energy production are feasible in their

local area.

2) Role: Student as a concerned citizen

3) Audience: Teacher and peers

4) Situation: Teacher short lecture on tidal generation. Teacher guided discussion of

tidal generation. Students write individual opinions on the effects of tidal power in

PA, and write a convincing letter to environmental groups in New Jersey to get

them to pressure the New Jersey State government for the implementation of tidal

power plants.

5) Product: The opinion piece on tidal power in PA (Delaware bay, and Lake Erie are

only 2 possible places), and the letter to the environmental groups in New Jersey.

Worth 8% of the grade for the unit.

6) Standards:

a) Opinion piece should detail areas that tidal power in PA is viable, possible

ways it could be implemented, and why it should or should not be

implemented.

39

b) Letter needs to list advantages of tidal power in a coherent way to convince the

environmental groups to support tidal generation in New Jersey. (Letter should

detail benefits to environment and how negative effects could be mitigated.

Backwards Design stage Three: The Learning Plan

Where: At the beginning of each lesson students are given a list of topics that are covered in the unit. At the beginning of every class the class objectives with learning outcomes are posted on the board, and gone over.

Unit Pacing

Lessons 1 through 4 address Eu # 2, EQ #2 and LO # 10 & 11

EU #2: Examples of all levels and areas of science are found in daily life and in modern

human developments

Q #2: In what ways will alternative energy generation impact life at the local through

global level?

LO #

10) Students will discuss the importance of alternative fuel sources

11) Students will describe the benefits and disadvantages of solar, wind, and tidal

Pre-test: Administered before the lessons in order to ascertain misconceptions and weaknesses. Weaknesses are evaluated and addressed during the lessons

Lesson 1

Do we need alternative fuel sources?

Hook: Students brainstorm in small groups reasons that we need fuel sources other than

fossil fuels.

40

Experience: Develop a class list of the reasons for alternative fuel sources. Students

read the E-zine article on why alternative fuels are needed. Students then compare their

list to the article, and decide to add or delete to the master list. Students then make

proposals for the county government to implement energy policy. Students must give

logical reasoning for the policies.

Resource: E-zine article: http://ezinearticles.com/?Alternative-Energy---Why-do-we-

Need-it?&id=801280

Reflection: Students are asked to reflect on alternative energies and discuss their ideas

and feelings on them in a large group discussion at the end of class.

Lesson 2

Solar Power

Hook: Today we are going to cook something in a pizza box using the sun as our energy

source.

Experience: Students perform a solar cooking lab. Students construct their group’s solar

oven in the first class period. The following class period students cook a muffin or

something they bring from home based upon teacher’s approval. During cooking

students read about solar energy and answer question about them.

Resources: Pizza box solar oven instruction:

http://www.reachoutmichigan.org/funexperiments/agesubject/lessons/other/solar.html

Solar energy information and quiz adapted from:

http://www.darvill.clara.net/altenerg/solar.htm

Reflection: Students are asked to describe the experience and relate it to their own lives.

Lesson 3

41

Wind Power

Hook: Who can build the best wind generator? Each lab group is a design team. The

team that designs the best wind generator gets a 5 point bonus added to the final

assessment.

Experience: Lab groups are given kits to build their own wind generator. The students

will then decide on what materials and shape to make the wind turbine. If students use

light weak materials, it will spin faster and be more efficient, but it will be less

dependable and prone to breaking. If students use the heavy most durable parts, it will

have poor efficiency, but better dependability. Students then write a critical analysis of

their design and offer ways to improve their design.

Resources: Instructions for building the turbine http://www.re-energy.ca/pdf/wind-

turbine.pdf

Reflection: Students are asked why wind power is not used more if it is easy enough for a

kid to do it.

Lesson 4 Tidal Power

Hook: How many gallons of water can you lift? How much energy does it take to move

an ocean? What if we used that energy to generate electricity?

Experience: Students discuss the advantages and disadvantages of generating tidal

power. Students also discuss the possible environmental effects of Tidal energy.

Students assess if tidal energy would have an impact on electricity generated in PA and

develop a proposal to build a tidal power station in New Jersey.

Resources: Tidal generation information: http://www.darvill.clara.net/altenerg/tidal.htm

42

Reflection: Students are asked to reflect on could all the Earth’s energy needs be met if

all of the power held in the tides is converted into usable energy.

Lesson 5 (Fully developed lesson) Nuclear Power

Nuclear fission

When a neutron is fired at a uranium-235 nucleus, the nucleus captures the neutron. It

then splits into two lighter elements and throws off two or three new neutrons (the

number of ejected neutrons depends on how the U-235 atom happens to split). The two

new atoms then emit gamma radiation as they settle into their new states. (John R.

Huizenga, "Nuclear fission", in AccessScience@McGraw-Hill,

http://proxy.library.upenn.edu:3725) There are three things about this induced fission

process that make it especially interesting:

4) The probability of a U-235 atom capturing a neutron as it passes by is fairly

high. In a reactor working properly (known as the critical state), one neutron

ejected from each fission causes another fission to occur. (Huizenga)

5) The process of capturing the neutron and splitting happens very quickly, on the

order of picoseconds (1x10-12 seconds). (Huizenga)

6) An incredible amount of energy is released, in the form of heat and gamma

radiation, when a single atom splits. The two atoms that result from the fission

later release beta radiation and gamma radiation of their own as well. The

energy released by a single fission comes from the fact that the fission

products and the neutrons, together, weigh less than the original U-235 atom.

The difference in weight is converted directly to energy at a rate governed by

the equation E = mc2. Something on the order of 200 MeV (million electron

volts) is released by the decay of one U-235 atom.4That may not seem like

much, but there are a lot of uranium atoms in a pound of uranium. A pound of

4 1 eV is equal to 1.602 x 10-12 ergs, 1 x 107 ergs is equal to 1 joule, 1 joule equals 1 watt-second, and 1 BTU equals 1,055 joules).

43

highly enriched uranium used to power a nuclear submarine is on the order of

a million gallons of gasoline. (Huizenga)

There are some drawbacks of nuclear fission reactors, namely:

5) Mining and purifying uranium has, historically, been a process that leaves very

toxic byproducts.

6) Improperly functioning nuclear power plants can create big problems. The

Chernobyl disaster is a good recent example that dramatically shows the worst-

case scenario. Chernobyl scattered tons of radioactive dust into the

atmosphere.

7) Spent fuel from nuclear power plants is toxic for centuries, and, as yet, there is

no safe, permanent storage facility for it. Yucca mountain in Nevada is the

future permenant depository when it becomes operational.

8) Transporting nuclear fuel to and from nuclear plants poses some risk, although

to date, the safety record in the United States has been good.

Nuclear Fusion

The sun releases energy through nuclear fusion reactions. The immense temperature and

pressure in the Sun forces hydrogen atoms fuse into deuterium, then the deuterium atom

fuses together with another hydrogen atom to form a tritium atom, and then the tritium

atom fuses with another hydrogen atom to from a helium atom. The resulting helium

atom’s mass is less than four hydrogen atoms. The missing mass is transformed into

energy by Einstein’s E=mc2 equation (Figures 1 and 2). The reaction between the nuclei

of the two heavy forms (isotopes) of hydrogen - deuterium (D) and tritium releases 17.6

MeV (2.8 x 1012 joule).

There are two methods of achieving nuclear fusion in a reactor. They are Inertial

Electrostatic Confinement (IEC) and toroidal magnetic field for confining a plasma

(Tokamak) Using these two methods different fuels can be used (Hydrogen, deuterium,

tritium, and helium-3) all with positive and negative attributes. In general most of the

positive attributes have to do with non-radioactive waste, and no danger of a meltdown.

44

The negative attributes with the hydrogen based fuels are abundant neutron production

which degrades the containment walls of reactors. The negative attributes of the helium-

3 based fuel is the limited availability of helium-3 on Earth, and high starting temperature

for the fusion of helium-3.

EU #1: Scientific knowledge is continually, although not steadily increasing and

changing through the results of experiments and the bridges built between experimental

observations and underlying concepts and theories

Q #1: Is nuclear energy a viable energy option?

LO #

12) Students will describe nuclear fusion and nuclear fission

13) Students will compare and contrast nuclear fission and fusion

14) Students will discuss the pros and cons of nuclear fission power generation

15) Students will discuss the problems with designing nuclear fusion reactors

Hook: We all know what nuclear bombs can do. Their destructive power is enormous.

Nuclear power has become one of the most feared power sources on the planet. Is this

fear justified? What are the real dangers and benefits behind nuclear Power?

Experience: Students will research nuclear power in small groups and design a

PowerPoint presentation that outlines the pros and cons of nuclear power generation, and

advocates a position of the building of nuclear power plants or a ban on the building of

nuclear power plants, and each will individually write a persuasive essay stating why

nuclear reactors should be pursued or banned.

45

Step one: Research nuclear processes

Students research the process of nuclear fission and nuclear fusion. Students need to

explain the process and energy released by both types on nuclear power

Step two: Students research the basic method by which nuclear fission plants operate.

Students research the parts of a reactor, the method of fission in the reactor, the cooling

of the reactor, and the waste generated by the reactor.

Step three: Pros and cons of nuclear fission

Students research the benefits and drawbacks of nuclear fission plants. Students need to

take into account economic costs and benefits, environmental costs and benefits, security

or safety costs and benefits, impact of added electrical generation to the public.

Step four: Nuclear fusion

Students research methods that nuclear fusion reactors operate. Students give

descriptions of reactors, the energy produced, and the waste generated by the reactor.

Step five: Pros and cons of nuclear fusion

Students research the benefits and drawbacks of nuclear fusion. Students need to take

into account whether it is worth it to continue research into fusion energy, the current

problems with fusion reactors, the benefits and drawbacks of helium 3 reactors and the

availability of helium 3 fuel.

46

Step six: Students write a persuasive essay stating why nuclear reactors should be

pursued or banned.

Resources: Nuclear Power project packet, computer with internet access, PowerPoint

Assessment: Project rubric for PowerPoint, student essay

Reflection: The student essay is the reflection for this activity.

Lesson 6 Energy flow through and between systems

EU #3: There are core concepts and processes in science that transcend the arbitrary

boundaries between traditional disciplines.

Q #3: How is energy described in physics, chemistry, & biology, and how are they

related?

LO #

16) Students will describe how energy is transformed from one form to another within

and without systems

17) Students will describe how energy leaves a system during an energy

transformation through non-conservative forces (friction, heat)

Hook: There is energy all around us. We are going to be detectives and determine the

possible paths different forms of energy take to become electricity in your home.

Experience: Energy flow using inspiration. Students use inspiration to follow the flow

of energy within and without different systems. Students are given a source of energy

and must describe the different transformations it goes through to generate electricity.

47

Example: Energy from the sun is used by plants to generate heat and to activate a

chemical reaction to form a carbohydrate and oxygen, that carbohydrate is compressed

over time and becomes coal, the coal is burned releasing the energy from the sun. The

activity shows students that the total amount of energy in the universe will always stay

constant.

Assessment: Inspiration energy flow sheets.

Reflection: Students are asked to reflect on why energy is so misunderstood in the world,

and what do they feel they do not understand about energy.

Resources:

1) Pizza box solar oven instruction:

http://www.reachoutmichigan.org/funexperiments/agesubject/lessons/other/solar.html

2) Solar energy information and quiz adapted from:

http://www.darvill.clara.net/altenerg/solar.htm

3) Instructions for building the turbine http://www.re-energy.ca/pdf/wind-turbine.pdf

4) Tidal generation information: http://www.darvill.clara.net/altenerg/tidal.htm

5) The International Atomic Energy Agency (IAEA) Gives great information on nuclear

rules and regulations around the world as well as explanations of fusion and fission

nuclear processes: http://www.iop.org/EJ/journal/NuclFus

6) Great site for nuclear power generation lessons and explanations (Nuclear Regulatory

Commission) : http://www.nrc.gov/reading-rm/basic-ref/teachers/unit3.html

7) Teacher’s domain on wind power and wind power resources:

http://www.teachersdomain.org/resources/psu06/energy21/sci/rotor/index.html

8) Great site for energy transformations specializing on alternative energy:

http://www.nvsd44.bc.ca/sites/ReportsViewOnePopM.asp?RID=3811

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Appendix:

1) Pretest

2) E-zine article: http://ezinearticles.com/?Alternative-Energy---Why-do-we-Need-

it?&id=801280

3) Nuclear power project packet

49

Appendix 1 Pre-test Name ___________________________ 1) Are coal, oil, and natural gas considered an alternative fuel? (Explain why or why

not) ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________ 2) What is the difference between nuclear fission and nuclear fusion? ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________ 3) Explain how wind power works. ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________ 4) Can energy be generated from the tides? If so, how? ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________ 5) What are the disadvantages to solar power? ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________

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6) Are alternative fuel sources needed? (Explain why or why not) ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________ 7) After energy is used, what happens to it? ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________ 8) Name an example when energy is generated without moving something. ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________ 9) Is there any difference between energy, power, and force. If so, explain them. ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________ 10) Is energy recycled? If so, how? ____________________________________________________________________ ____________________________________________________________________ ____________________________________________________________________

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Appendix 2

http://ezinearticles.com/?Alternative-Energy---Why-do-we-Need-it?&id=801280

Why Do We Need Alternatives?

To answer that question, we need to start by discussing fossil fuels-what they are,

where they come from, how they are used and the advantages and disadvantages of each. Within this context, the pressing need for alternatives becomes quite clear.

What are fossil fuels?

Most fossil fuels are formed from the remains of long-dead creatures and plants.

Buried over the course of hundreds of millions of years, these carbon-based deposits

have been converted by heat and pressure over time into such combustible

substances as crude oil, coal, natural gas, oil shales and tar sands. A smaller portion

of fossil fuels is the handful of other naturally occurring substances that contain carbon but do not come from organic sources.

To make more fossil fuels would require both the creation of new topsoil filled with

hydrocarbons, and time-lots of time. Given estimates of current fossil fuel reserves

worldwide, it's not possible we can wait out the problem, and continue our

dependence on fossil fuels until new reserves are built. At current consumption rates,

the reserves of oil and coal and other fossil fuels won't last hundreds of years, let

alone hundreds of millions of years.

As for creating more, experts have pointed out that it can take close to five centuries

to replace a single inch of topsoil as plants decay and rocks weather. Yet in the

United States, at least, much of the topsoil has been disturbed by farming, leading

still more experts to the disturbing conclusion that in areas once covered by prairie,

the past hundred years of agriculture have caused America's "bread basket' to lose half of its topsoil as it erodes thirty times faster than it can form.

The Advantages of Fossil Fuels in Energy Production

There are many reasons why the world became dependent on fossil fuels, and

continues to rely on them. For example, it has so far been relatively cost-effective in

the short run to burn fossil fuels to generate electricity at strategic centralized parts

of the grid and to deliver the electricity in bulk to nearby substations; these in turn

deliver electricity directly to consumers. These big power plants burn gas or, less

efficiently, coal. Since so much electricity can be lost over long-distance

transmission, when power needs to be concentrated more in one region than

another, the fuels are generally transported instead to distant power plants and

burned there. Liquid fuels are particularly easy to transport.

Thus far, fossil fuels have been abundant and easily procured. Petroleum reserves

worldwide are estimated at somewhere between 1 and 3.5 trillion barrels. Proven

coal reserves at the end of 2005, as estimated by British, were 909,064 million tons worldwide. Coal, furthermore, is relatively cheap.

52

Perhaps the simplest reason why the world continues to depend on fossil fuels is that

to do anything else requires change: physical, economical, and-perhaps the most

difficult-psychological. The basic technology for extracting and burning fossil fuels is

already in place, not only in the large power plants but at the consumer level, too.

Retrofitting factories would be cost-prohibitive, but perhaps even more daunting

would be replacing heating systems in every home, factory and building. Ultimately,

however, the true resistance may be our nature. We humans tend to resist change in

general, and in particular those changes that require us to give up longstanding

traditions, alter our ways of thinking and living, and learn new information and

practices after generations of being assured that everything was "fine" with the old

ways.

Why Do We Need Alternatives?

If there are so many reasons to use fossil fuels, why even consider alternatives?

Anyone who has paid the least bit of attention to the issue over the past few decades

could probably answer that question. If nothing else, most people could come up

with the first and most obvious reason: fossil fuels are not, for all practical purposes,

renewable. At current rates, the world uses fossil fuels 100,000 times faster than

they can form. The demand for them will far outstrip their availability in a matter of centuries-or less.

And although technology has made extracting fossil fuels easier and more cost

effective in some cases than ever before, such is not always the case. As we deplete

the more easily accessible oil reserves, new ones must be found and tapped into.

This means locating oil rigs much farther offshore or in less accessible regions;

burrowing deeper and deeper into the earth to reach coal seams or scraping off ever

more layers of precious topsoil; and entering into uncertain agreements with

countries and cartels with whom it may not be in our best political interests to forge such commitments.

Finally, there are human and environmental costs involved in the reliance on fossil

fuels. Drilling for oil, tunneling into coalmines, transporting volatile liquids and

explosive gases-all these can and have led to tragic accidents resulting in the

destruction of acres of ocean, shoreline and land, killing humans as well as wildlife

and plant life. Even when properly extracted and handled, fossil fuels take a toll on

the atmosphere, as the combustion processes release many pollutants, including

sulfur dioxide-a major component in acid rain. When another common emission,

carbon dioxide, is released into the atmosphere, it contributes to the "greenhouse

effect," in which the atmosphere captures and reflects back the energy radiating

from the earth's surface rather than allowing it to escape back into space. Scientists

agree that this has led to global warming, an incremental rise in average

temperatures beyond those that could be predicted from patterns of the past. This affects everything from weather patterns to the stability of the polar ice caps.

Conclusion

Clearly, something must change. As with many complex problems, however, the

solution to supplying the world's ever-growing hunger for more energy will not be as

simple as abandoning all the old methods and beliefs and adopting new ones

overnight. Partly this is a matter of practicality-the weaning process would take

considerable investments of money, education and, most of all, time. The main

53

reason, however, is that there is no one perfect alternative energy source. Alternative will not mean substitute.

What needs to change?

It seems simplistic to say that what really needs to change is our attitude, but in fact

the basis of a sound energy plan does come down to the inescapable fact that we

must change our way of thinking about the issue. In the old paradigm, we sought

ways to provide massive amounts of power and distribute it to the end users,

knowing that while much would be lost in the transmission, the advantages would be

great as well: power plants could be located away from residential areas, fuels could

be delivered to central locations, and for consumers, the obvious bonus was

convenience. For the most part our only personal connection with the process would

be calling the providers of heating fuel and electricity, and pulling up to the pumps at

the gas station. And the only time we would think about the problem would be when

prices rose noticeably, or the power went out.

There are people who have tried to convince us that there is no problem, and that

those tree-hugging Chicken Littles who talk about renewable and alternative energy

want us all to go back to nature. More often than not these skeptics' motivations for

perpetuating this myth falls into one of two categories: one, they fear what they

don't understand and are resistant to being told what to do, or two, they have some political or financial stake in enabling our fossil-fuel addiction. (And sometimes both.)

The reality is that except for altering our ways of thinking, there will not be one

major change but a great many smaller ones. A comprehensive and successful energy plan will necessarily include these things:

• Supplementing the energy produced at existing power plants with alternative

energy means, and converting some of those plants to operate on different

"feedstock" (fuels)

• Shifting away from complete reliance on a few concentrated energy

production facilities to adding many new and alternative sources, some

feeding into the existing "grid" and some of supplying local or even

individual needs

• Providing practical, economical and convenient ways for consumers-

residences, commercial users, everyone-to adapt and adopt new

technologies to provide for some or all of their own energy needs

• Learning ways in which we can use less energy now ("reduce, reuse,

recycle"), using advances in technology as well as simple changes in

human behavior to reduce consumption without requiring people to make major compromises or sacrifices

Alternative Energy is a crucial link in our energy future if we are to cut the oil cord.

We present thoughts, ideas, info and news about alternative energy at Alternative

Energy HQ. Get a free copy of our book "Cutting the Oil Cord - Using Alternative

Energy in Your Life" at - http://alternativeenergyhq.com

Article Source: http://EzineArticles.com/?expert=Kevin_Rockwell

54

Appendix 3

Nuclear Power Project

Introduction We all know what nuclear bombs can do. Their destructive power is enormous. Nuclear power has become one of the most feared power sources on the planet. In this project we will decide if nuclear power should be feared and what is being done to make it safer.

Basic task Students will research nuclear power in groups of four, design a PowerPoint presentation that outlines the pros and cons of nuclear power generation, and advocates a position of the building of nuclear power plants or a ban on the building of nuclear power plants, and each will individually write a persuasive essay stating why nuclear power should be pursued or banned.

Process Step one: Research nuclear processes

Students research the process of nuclear fission and nuclear fusion. Students need to

explain the process and energy released by both types on nuclear power

Step two: Students research the basic method by which nuclear fission plants operate.

Students research the parts of a reactor, the method of fission in the reactor, the cooling

of the reactor, and the waste generated by the reactor.

Step three: Pros and cons of nuclear fission

Students research the benefits and drawbacks of nuclear fission plants. Students need to

take into account economic costs and benefits, environmental costs and benefits, security

or safety costs and benefits, impact of added electrical generation to the public.

Step four: Nuclear fusion

55

Students research methods that nuclear fusion reactors operate. Students give

descriptions of reactors, the energy produced, and the waste generated by the reactor.

Step five: Pros and cons of nuclear fusion

Students research the benefits and drawbacks of nuclear fusion. Students need to take

into account whether it is worth it to continue research into fusion energy, the current

problems with fusion reactors, the benefits and drawbacks of helium 3 reactors and the

availability of helium 3 fuel.

Step six: Students write a persuasive essay stating why nuclear reactors should be

pursued or banned. Essay needs to have a clear pro/con nuclear power argument. You

may be for one method of nuclear power and against the other. Every point made in the

essay should be backed by facts presented in the PowerPoint or referenced at the end of

the essay. The essay should be at least 200 words and no more than 800 words.

Assessment:

Nuclear Power Rubric

Not Present Poor Proficient Excellent

Fission 0 5 11 15 Process

Fusion 0 5 11 15

Fission 0 4 8 10 Safety

Fusion 0 4 8 10

Fission 0 4 8 10 Wastes

Fusion 0 4 8 10

Fission 0 5 11 15 Cost/Benefit

Fusion 0 5 11 15

Essay Nuclear Energy

0 7 14 20

References Sources of information

0 3 6 10

Total Score ____________

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(Total score/130) x 100% = ____________ Process: Not present scores reflect no explanation of the process of nuclear reactions, Poor scores reflect little more than the mention of nuclear reactions with very little coherent detail on the process, Proficient scores reflect a coherent organized description of nuclear reactions and why/how they result in the release of energy, Excellent scores reflect an understanding of why/how fusion and fission only work for particular elements. Safety: Not present scores reflect no mention of the safety issues for each kind of nuclear power, Poor scores reflect on incomplete development of topic where possible hazards and past failures are not covered effectively, Proficient scores reflect through listing and explanation of safety issues facing nuclear power, Excellent scores reflect a through listing and explanation of safety issues facing nuclear power, and ways the industry is trying to mitigate dangers. Wastes: Not present scores reflect little to no mention of nuclear wastes, Poor scores reflect types of waste with no description of how they are processed, Proficient scores reflect the types of waste generated and how they are processed and stored, Excellent scores reflect the types of waste generated and how they are processed and stored, and detail methods for handling wastes in the future. Cost/Benefit: Not present scores reflect no attention to the cost/benefit breakdown of nuclear power, Poor scores reflect little thought or research into nuclear power, Proficient scores reflect a logical breakdown of the benefits and drawbacks (economic, environmental)to nuclear power, Excellent scores reflect a logical breakdown of the benefits and drawbacks (economic, environmental)to nuclear power, and include a reasoned approach to whether either form of nuclear power should be utilized to meet the energy needs now and in the future. Essay: This is the individual section of the essay. This is where you show your understanding of nuclear power and is independent of group work. Not present scores reflect not submitting an essay, Poor scores reflect little coherent knowledge of nuclear processes and the debate on the future of nuclear energy, Proficient scores reflect coherent knowledge of nuclear processes and the debate on the future of nuclear energy, Excellent scores reflect clear understanding of nuclear processes and a command of the issues facing nuclear power today. References: Not present reflects no references provided, Poor reflects 1- 3 references provided, Proficient reflects 4-6 references provided, Excellent reflects more than 6 references in MLA format

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References (Pedagogy Section)

Wiggins, g., McTighe, J. (2005) Understanding by design, New York: Prentice Hall

Miriam Reiner, James D. Slotta, Michelene T. H. Chi and Lauren B. Resnick (2000), Naive Physics Reasoning: A Commitment to Substance-Based Conception, Cognition and Instruction, Vol. 18, No. 1, pp. 1-34

John P. Smith, III, Andrea A. diSessa and Jeremy Roschelle (1993 – 1994), Misconceptions Reconceived: A Constructivist Analysis of Knowledge in Transition, The Journal of the Learning Sciences, Vol. 3, No. 2, pp. 115-163

Jones, B. F., Idol, L., (1990), Dimensions of thinking and cognitive instruction: Implications for Educational Reform, Lawrence Erlbaum Associates Clement, J. (1987). Overcoming students' misconceptions in physics: The role of anchoring intuitions and analogical validity. In J. Novak (Ed.). Proceedings of the second international seminar misconceptions and educational strategies in science and mathematics. (Vol. III, pp. 84-96). Ithaca, NY: Cornell University.

Chong, L. (2005), Making sense of learning with schemas. CDTLink Teaching Methods, Vol 9, No 1