Teacher Guide .......................................................... 2

Related National Science Standards.......................... 3

Introduction to Ocean Energy .................................. 4

Petroleum & Natural Gas ......................................... 5

Natural Oil and Gas Seeps ........................................ 7

Methane Hydrates .................................................... 8

Solar Energy.............................................................. 9

Wind Energy ........................................................... 10

Wave Energy ........................................................... 11

OTEC: Ocean Thermal Energy Conversion ............. 12

Tidal Energy............................................................ 13

Activity 1: Exploring Oil Seeps ............................... 14

Activity 2: Drilling for Oil in the Ocean.................. 15

Activity 3: A Stationary Oil Rig ............................... 16

Activity 4: A Floating Oil Rig .................................. 17

Activity 5: Exploring Currents ................................ 18

Activity 6: Exploring Wave Energy.......................... 19

Activity 7: Exploring Wind Energy.......................... 20

  	



Special thanks to the National Energy Education Development (NEED) Project

for development of this booklet. For more information about NEED, go to www.NEED.org.

Cover design by Will Waskes, MMS.

	
 	
	 
	
				

Teacher Guide

  	
 	 
  	  


 	
   	 	
 


 
 
 

BACKGROUND

The ocean environment has many energy resources, both renewable and nonrenewable. As new technologies are

developed, ocean resources will be able to meet many of the Nation’s energy needs.

TIME

Three to ten class periods, depending on the number of hands-on activities you choose to conduct.

MATERIALS

■ Four copies of the backgrounder.

■ Nine poster boards.

■ The materials listed for each activity you choose to conduct on pages 16-22.

PROCEDURE

	




 Divide the class into nine groups.

 Make four copies of the backgrounder and separate by the nine topics––Introduction to Ocean Energy, Petroleum

& Natural Gas, Natural Oil Seeps, Methane Hydrates, Solar Energy, Wind Energy, Wave Energy, Ocean Thermal

Energy Conversion, Tidal Energy.

 Gather materials for the activities you choose to conduct.

 


 
   

Introduce the activity to the class. Explain to the students that they will be working in small groups to prepare a twominute presentation on one aspect of ocean energy to teach to the class. Distribute the backgrounders to the groups.

Give students the timeframe within which they are to accomplish their goals. If this will be a graded activity, explain the

grading procedure. Have the students read their backgrounders. Answer any questions the students may have.

 
	


 
 	

  


Give the groups one class day to prepare their presentations. Encourage them to make posters for illustration.

 

	

  


Let’s take the plunge—into the ocean of energy resources. Have each group make its presentation in turn.

  
   



Have the students conduct the hands-on activities you have chosen.
	
	 
	
				 	



INT–B: 3.a Energy is a property of many substances and is associated with heat, light, electricity, mechanical motion,

sound, nuclei, and the nature of a chemical.

INT–B: 3.b Energy is transferred in many ways.

INT–B: 3.g The sun is the major source of energy for changes on the earth’s surface. The sun loses energy by

emitting light. A tiny fraction of that light reaches earth, transferring energy from the sun to the earth.

The sun’s energy arrives as light with a range of wavelengths.

INT–D: 1.b Water, which covers the majority of the earth’s surface, circulates through the crust, oceans, and atmosphere in what is known as the water cycle.

INT–D: 3.a Gravity governs the motion in the solar system. Gravity explains the phenomenon of the tides.

INT–D: 3.b The sun is the major source of energy for phenomena on the earth’s surface, such as the growth of

plants, winds, ocean currents, and the water cycle.

INT–E: 2.c Technological solutions are temporary and have side effects. Technologies cost, carry risks, and have

benefits.

INT–E: 2.f Perfectly designed solutions do not exist. All technological solutions have trade-offs, such as safety, cost,

efficiency, and appearance. Risk is part of living in a highly technological world. Reducing risk often

results in new technology.

INT–E: 2.g Technological designs have constraints. Some constraints are unavoidable, such as properties of materials, or effects of weather and friction. Other constraints limit choices in design, such as environmental

protection, human safety, and aesthetics.

INT–F: 1.b Natural environments may contain substances that are harmful to human beings. Maintaining environmental health involves establishing or monitoring quality standards related to use of soil, water, and air.

Related National Science Standards

(Intermediate Level)

	
 	
	 
	
				

Introduction to Ocean Energy

If you stand on the beach on a sunny day and look out at the ocean, you are surrounded by energy. You feel

the radiant energy from the sun warming your skin. The energy in the wind blows your hair. The waves are

constantly advancing and retreating. If you stand long enough, you will see the water level rise and fall with

the tides. Powerful currents, unseen, move through the oceans. Energy is everywhere around you, just waiting

to be harnessed.

Below the ocean, there are enormous energy resources, too. In many areas, large deposits of petroleum and

natural gas are buried under the seabed. There are huge deposits of frozen crystals filled with methane, an

energy-rich gas. The ocean is full of energy.

Oceans cover almost three-fourths of the earth’s surface. The oceans and the land

beneath them could provide all of the energy the world needs for years to come.

Today, more than a fourth of the oil and gas produced in the United States comes

from offshore areas.

The beach extends from the shore into the ocean on a continental shelf that

gradually descends to a sharp drop, called the continental slope. This continental

shelf can be as narrow as 20 kilometers or as wide as 400 kilometers. The water

on the continental shelf is shallow, rarely more than 150 to 200 meters deep.

The continental shelf drops off at the continental slope, ending in abyssal plains that are three to five

kilometers below sea level. Many of the plains are flat, while others have jagged mountain ridges, deep

canyons, and valleys. The tops of some of these mountain ridges form islands where they extend above

the water.

When most people think of the United States, a

map of the country comes to mind. Everyone recognizes the outline of the USA. But our resources

aren’t confined to our land area. Our borders extend 200 miles into the water from our coastlines

and encompass an area larger than the country

itself. The underwater area claimed by the United

States includes 3.9 billion acres; the land area of

the country includes only 2.3 billion acres.

This large underwater area is called the Exclusive

Economic Zone (EEZ). In 1983, the President

claimed all the area of the EEZ in the name of the

United States. The Minerals Management Service of

the U.S. Department of the Interior is responsible for

protecting and developing its natural resources.

	



	

	

	



	







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Petroleum and Natural Gas

Petroleum and natural gas deposits are found in sedimentary rock basins, where tiny sea plants and animals

died millions of years ago. If the proper temperature and pressure were present, these plants and animals

eventually turned into hydrocarbons. Oil and gas are made mostly of hydrogen and carbon—hydrocarbons.

These hydrocarbons flowed into empty spaces in the surrounding rocks, called traps. Finally, an oil-soaked

rock—much like a wet sponge—was formed. The traps were covered with a layer of solid rock, or a seal of salt

or clay, that kept the oil and gas from escaping to the surface.

Thirty basins in the EEZ have been found that could contain enormous oil and gas deposits. Some of these

basins have been explored and are producing oil and gas at this time. Scientists estimate that 30 percent of

U.S. gas and oil reserves are in these offshore basins.

Studies have been carried out on many of these basins to determine the amount of oil and gas in them and

the environmental impacts of recovering them. Studies of the ocean currents and climate in potential drilling

areas have also been done to find out the risks to drilling platforms. Test wells have been drilled

in many areas.

The first offshore drilling was begun in 1897 from a pier in California. Early drilling was

limited to areas where the water was less than 300 feet deep, but modern drilling rigs can

operate to depths of a mile or more. Some drilling platforms stand on stilt-like legs that

are imbedded in the ocean floor. These huge platforms hold all the drilling equipment,

as well as housing and storage areas for the

work crews. Once the wells have been

drilled, the platforms also hold the production equipment.

Floating platforms are used for drilling

in deeper waters. These self-propelled

vessels are anchored to the ocean bottom with huge cables. Once the wells

have been drilled from these platforms,

the production equipment is lowered

to the ocean floor and sealed to the

well casing to prevent leakage. Wells

have been drilled in 10,000 feet of

water using these floating rigs.



	
















 










 



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During every phase of development and production, precautions are taken to prevent pollution, spills, and significant changes to the ocean environment. All aspects of the

operation, from waste disposal to hurricane safety measures, are regulated.

Since 1975, the offshore program has had a safety record

of 99.99 percent—only about 0.001 percent of the oil produced has been spilled. During 1993, Hurricane Andrew

passed through the Gulf of Mexico with winds of 140 mph

and 35-foot waves and no major spills or injuries occurred.

In 1954, there were only 100 offshore wells drilled in the

U.S. In 1978, four years after the first oil embargo, there

were more than 1,200 new wells drilled.

Then, in 1990, President Bush excluded the Pacific Coast,

the North Atlantic and North Aleutian areas, and parts of

the Eastern Gulf of Mexico from drilling until the year 2000.

In 1992, there were only 600 new wells drilled. In 1993,

the energy picture changed and increased use of natural

gas spurred the development of 800 new wells.

In December 1997, President Clinton extended the moratorium for another ten

years. The oil and gas basins with the highest potential for development are included

in this moratorium.

Today, there are more than 4,000 platforms

in the Gulf of Mexico and off the coasts of

California and Alaska, servicing thousands

of wells. Offshore production supplies approximately 27 percent of the Nation’s

natural gas and 20 percent of its oil. Most

of the active wells and proven reserves are

in the Gulf of Mexico. Although there are

no producing wells in other areas, there is

believed to be significant petroleum in the

Beaufort Sea off Alaska, as well as natural

gas in the Eastern Gulf of Mexico and off

the Atlantic Coast.

Although there is public concern about development of these areas right now, they

offer great potential for the future. Today,

the U.S. imports about two-thirds of the

petroleum it consumes, much of it from

politically unstable areas of the world. Consumption of natural gas continues to increase, too. In the future, we might need

to develop offshore resources that are currently under restriction to meet our

society’s demand for energy.

	


	

	
		

	


 	 

	


	 	 	  	




					

		





		
	
	

			


		 
 
 	 
	  


 	




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Natural Oil and Gas Seeps

Millions of years ago, large deposits of petroleum and natural gas formed in

basins along the coast of California. Over time, earthquakes caused cracks

in the layers of rock that covered the deposits. The petroleum and natural

gas began oozing through the cracks. This natural oozing of oil and gas is

called a seep.

Natural seeps have occurred for thousands of years and are still occurring

today. The petroleum and natural gas rise through the water to the surface.

The natural gas eventually dissipates into the air, but the petroleum congeals into floating balls of sticky tar that are carried by ocean currents to

local beaches, especially during the summer months.

The early explorer Juan Rodriquez Cabrillo, who arrived in the area in 1542,

made a record of the oil floating on the ocean. The Chumash Tribe of Native

Americans gathered the tar and used it for many tasks. They waterproofed

woven bottles and mended cracks in bowls and other cooking vessels. They

coated their sewing string and fishing spears and used the tar to make pipes

and whistles. They also used the heavy tar to waterproof their ocean-going

canoes so that they could travel and trade throughout the region.

In the 1880’s, the Santa Barbara Area gained a reputation as a health resort,

in large part because of the winds blowing over the seeps toward the town.

People believed the oil and gas purified the atmosphere and helped cure

many chronic diseases. Now we know these seeps are the largest source of

air pollution in Santa Barbara County.

According to the California State Lands Commission, more than 1,200 natural seeps have been charted in the Santa Barbara Channel of California. It is

estimated that 130-150 barrels of oil a day seep to the surface.

There are 42 gallons of oil per barrel, which equals more than two

million gallons a year. In addition,

five million cubic feet of natural gas

seep through the ocean and into

the air each day, or almost two trillion cubic feet per year.

In 1982, several oil companies built

two steel pyramids, called tents, to

capture the natural gas from one

gigantic seep. These 50-foot high

tents weigh 350 tons each and

measure 100 feet on each side.

They capture more than a half million cubic feet of seeping gas each

day, an amount equal to the pollution from thousands of cars.

	


	





	




	










 





	




	




	






	



  





 













		
 	
	 
	
				

Methane Hydrates

Methane is an energy-rich gas, the main component of natural gas. Buried in

the sediments of the ocean floor is a reserve of methane so huge it could fuel

the whole world. In the sediments, bacteria break down the remains of sea

animals and plants. In the process, they produce methane gas. Methane is

almost always a by-product of organic decay. Under the enormous pressures

and cold temperatures at the bottom of the ocean, this methane gas dissolves. The molecules of methane become locked in a cage of water molecules to form crystals. These crystals look like ice, and they cement together

the ocean sediments. In some places a solid layer of crystals—called methane

hydrate—extends from the sea floor down hundreds of meters.

In addition to the methane trapped in crystals, scientists think that huge deposits of free methane gas are

trapped beneath the hydrate layer. The methane in hydrates is very concentrated. The molecules of methane

are packed together more closely in hydrates than in liquefied gas. Hydrates are the richest reservoirs of

methane known to exist. Researchers estimate that there is more carbon trapped in hydrates than in all the

fossil fuels—an enormous amount of energy.

Some of this methane is trapped in polar ice, but most is located in the waters off the East and West coasts, as

well as Alaska. One deposit in a 30-by-100 mile area off the North Carolina coast holds enough methane to

supply all the needs of the U.S. for 100 years. The challenge is to recover this methane safely and economically.

We know that most of the hydrates are not hard to reach. They are located in ocean waters at depths of 1,000

to 3,000 meters. Drilling rigs in the Gulf of Mexico operate in much deeper water. Researchers think that it

may be simple to free the methane from the crystals by reducing the pressure on them.

The Russians have used antifreeze to break down hydrates located on-shore in Siberia. Some researchers think

that warm surface water could be piped to the bottom of a hydrate zone to melt it, while other pipes could

vent the gas to the surface. Refining this technique, however, could take years of research. Perhaps the biggest

question is the effect that removing the methane will have on the environment. When methane is removed

from a hydrate, it loses its solidity and turns into mush. This could cause major landslides and other disturbances to the ocean floor.

Recovery efforts might also cause an increase in methane escaping

into the atmosphere. Methane is a greenhouse gas and scientists think that methane from ocean hydrates has an impact

on global climate. During the Ice Age, for example, sea

levels dropped as the water became frozen on land.

As the sea level dropped, the pressure decreased,

causing hydrates to melt and release huge

amounts of methane into the air. Researchers

think this caused a greenhouse effect that

warmed the earth, moderating the temperatures.

In warmer periods, as glaciers and ice caps

melted, the sea levels rose and increased the

pressure on the hydrates. Less methane escaped

into the atmosphere. This, in turn moderated

the climate. Any wide-scale attempts to harvest

methane from ocean hydrates will have to take

into account the environmental impacts to the

ocean floor and the atmosphere. Much research

must be done before methane hydrate becomes

a usable energy source for the future.



	



 




  


  
 




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Solar Energy

Every day, the sun radiates an enormous amount of energy. This energy comes from

within the sun itself. Like most stars, the sun is a big gas ball made mostly of hydrogen and helium. The sun produces energy in a process called nuclear fusion. The

high pressure and temperature in the sun’s core cause hydrogen atoms to split

apart. Four hydrogen nuclei combine, or fuse, to form one helium atom, producing

radiant energy in the process.

The sun radiates more energy in one second than the

world has used since time began. Only a small portion of this energy strikes the earth, one part in two

billion. Yet this amount of energy is enough to meet

the world’s needs, if it could be harnessed. About 15

percent of the radiant energy that reaches the earth is

reflected back into space. Another 30 percent is used

to evaporate water, which is lifted into the atmosphere

and produces rainfall. The radiant energy is also absorbed by plants, landmasses, and the oceans.

Oceans cover more than 70 percent of the earth’s surface and most of the ocean’s energy comes from the

sun. Only the tides—caused by the gravitational energy of the moon—and the geothermal energy under the oceans are not solar powered. Ocean currents,

waves, and winds all are a result of the sun’s radiant

energy. Solar energy can also be used to produce electricity with photovoltaics.

Photovoltaic comes from the words photo (meaning light) and volt, a measurement of electricity. Photovoltaic cells are also called PV cells or solar cells. You are probably familiar with photovoltaic cells in solar-powered toys and calculators. The main disadvantage of PV cells is that they cannot produce electricity all the time.

Photovoltaic cells are made of two thin pieces of silicon,

the substance that makes up sand. One piece of silicon has

a small amount of boron added to it, which gives it a tendency to attract electrons. The other piece of silicon has a

small amount of phosphorous to it, giving it an excess of

free electrons. When the two pieces of silicon are placed

together, an electric field forms between the layers. When

the PV cell is placed in the sun, the radiant energy energizes the free electrons. If a circuit is made connecting the

layers, electrons flow from the n-layer through a wire to the

p-layer, producing electricity.

Compared to other ways of generating electricity, PV systems are expensive, but they are a good way to produce

electricity in remote areas. Some offshore platforms have

begun using PV systems to generate the electricity they

need. One international energy company has designed solar systems to power radio communications, helicopter landing pad lights, and navigation warning lights on offshore

platforms. Ocean buoys and other monitoring equipment

also have PV cells as a power source.









	








 	




 




	
 	
	 
	
				

Wind Energy

Wind is air in motion. It is produced by the uneven heating of the earth’s surface by

the sun. Since the earth’s surface is made of various land and water formations, it

absorbs the sun’s radiation unevenly. When the sun is shining during the day, the air

over landmasses heats more quickly than the air over water. The warm air over the

land expands and rises, and the heavier, cooler air over the water moves in to take

its place, creating local winds. At night, the winds are reversed because the air over

land cools more rapidly than the air over water. Similarly, the large atmospheric

winds that circle the earth are created because the surface air near the equator is

warmed more by the sun than the air over the North and South Poles.

Wind energy is mainly used to generate electricity. Windmills work by slowing down the speed of the wind. The

wind flows over the airfoil-shaped blades causing lift, like

the effect on airplane wings, causing them to turn. The

blades are connected to a drive shaft that turns an electric generator to produce electricity. Wind turbines are

being installed on offshore oil and gas platforms in many

areas to generate power to operate the equipment.

For wind machines to be economical, there must be winds

that blow consistently above 10-14 miles per hour. Many

offshore areas have ideal wind conditions for wind machines. Denmark and the United Kingdom have installed

large offshore wind parks to take advantage of the consistent winds. Several offshore parks are planned for the

United States in the near future, including one in Nantucket Sound and one off Long Island, NY.









 
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Wave Energy

Waves are caused by the wind blowing over the

surface of the ocean. In many areas of the world,

the wind blows with enough consistency and force

to provide continuous waves. There is tremendous

energy in the ocean waves. The total power of waves

breaking on the world’s coastlines is estimated at

2-3 million megawatts. The west coasts of the

United States and Europe and the coasts of Japan

and New Zealand are good sites for harnessing

wave energy.

One way to harness wave energy is to bend or focus the waves into a narrow channel, increasing their

power and size. The waves can then be channeled

into a catch basin, like tidal plants, or used directly

to spin turbines. There aren’t any big commercial

wave energy plants, but there are a few small ones.

Small, on-shore sites have the best potential for the

immediate future, especially if they can also be used

to protect beaches and harbors. They could produce enough energy to power local communities.

Japan, which must import almost all of its fuel, has

an active wave-energy program.

Another way to harness wave energy is with an Oscillating Water Column (OWC) that generates electricity

from the wave-driven rise and fall of water in a cylindrical shaft or pipe. The rising and falling water drives air

into and out of the top of the shaft, powering an air-driven turbine. In Norway, a demonstration tower that is

built into a cliff produces electricity very economically using this method. The wail of the fast-spinning turbines, however, can be heard for miles.

Float devices can generate electricity from the bobbing action of a floating object. The object can be mounted to a

floating raft or to a device fixed on the ocean floor. These

types of devices can power lights and whistles on buoys.



	



	


 
	


 




 
	

 	
 
 	





 





	 


 	
 





	






		



	















	


	


	

		


			

			

	

	
 	
	 
	
				

Turbine

Generator

Evaporator Condenser

Water Vapor

Electricity

Transmission Cable

Water Vapor

Fresh

Water

Drain

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Cold Deep

Seawater

3 - 7 CO

Drain

Water

Warm Surface

Seawater

25 - 35 CO

OTEC––Ocean Thermal Energy Conversion

The energy from the sun heats the surface water of the ocean.

In tropical regions, the surface water can be 40 or more

degrees warmer than the deep water. This temperature difference can be used to produce electricity. Ocean Thermal

Energy Conversion (OTEC) has the potential to produce

more energy than tidal, wave, and wind energy combined.

The OTEC systems can be open or closed. In a closed system, an evaporator turns warm surface water into steam

under pressure. This steam spins a turbine generator to produce electricity. Water pumps bring cold deep water through

pipes to a condenser on the surface. The cold water condenses the steam, and the closed cycle begins again. In an

open system, the steam is turned into fresh water, and new

surface water is added to the system. A transmission cable

carries the electricity to the shore.

The OTEC systems must have a temperature difference of

about 25 degrees Celsius to operate. This limits OTEC’s use

to tropical regions where the surface waters are very warm

and there is deep cold water. Hawaii, with its tropical climate, has experimented with OTEC systems since the 1970’s.

Today, there are several experimental OTEC plants, but no large operations. There are many challenges to

widespread use. The OTEC systems are not very energy efficient. Pumping the water is a giant engineering

challenge. In addition, the electricity must be transported to land. It will probably be 10 to 20 years before the

technology is available to produce and transmit electricity economically from OTEC systems.











	
	





	




	
	 
	
				 	



Tidal Energy

The tides rise and fall in eternal cycles. Tides are changes in the level of the oceans caused by the gravitational

pull of the moon and sun, and the rotation of the earth. Nearshore water levels can vary up to 40 feet,

depending on the season and local factors. Only about 20 locations have good inlets and a large enough

tidal range—about 10 feet—to produce energy economically.

The generation of electricity from tides is similar to hydroelectric generation, except that tidal water flows in

two directions. The simplest generating system for tidal plants involves a dam, known as a barrage, across an

inlet. Sluice gates on the barrage allow the tidal basin to fill on the incoming high tides and to empty through

the turbine system on the outgoing tide, known as the ebb tide. Flood-generating systems that generate

power from the incoming tide are possible, but are less favored than ebb generating systems. Two-way generation systems, which generate electricity on both the incoming and ebb tides, are also possible.

The construction of a tidal barrage in an inlet can change the tidal level

in the basin. It can also have an effect on the sedimentation and turbidity of the water within the basin. In addition, navigation and recreation

can be affected. A higher tidal level can cause flooding of the shoreline,

which can affect the local marine food chain. Potentially the largest

disadvantage of tidal power is the effect a tidal station has on the plants

and animals that live within an estuary. Since few tidal barrages have

been built, very little is known about the full impact of tidal power

systems on the local environment. In every case, it will depend on the

local geography and marine ecosystem.

There are currently two commercial sized barrages in operation—a 240 MW turbine at La Rance, France, and

a 16 MW plant at Annapolis Royal, Nova Scotia, Canada. Several other tidal power stations are being considered, including the Severn project in England. The United States has no tidal plants and only a few sites where

tidal energy could be produced economically. France, England, Canada and Russia have much more potential. The keys are to lower construction costs, increase output, and protect the environment.

Tidal fences can also harness the energy in the tides. A tidal fence has vertical

axis turbines mounted within a fence structure called a caisson that completely blocks a channel, forcing all of the water through it. Unlike barrage

stations, tidal fences can be used in unconfined basins, such as in a channel

between the mainland and a nearby offshore island, or between two islands.

As a result, tidal fences have much less impact on the environment, because

they do not require flooding the basin. They are also significantly cheaper to

install. Tidal fences have the advantage of being able to generate electricity

once each individual module is installed. Tidal fences are not free of environmental and economic impacts, however, since the caisson can disrupt the

movement of large marine animals and shipping. A 55MW tidal fence is

planned for the San Bernadino Strait in the Philippines.

Tidal turbines are a new technology that

can be used in many tidal areas. Tidal

turbines are basically wind turbines that

can be located wherever there is strong

tidal flow, as well as in river estuaries.

Since water is about 800 times as dense

as air, tidal turbines will have to be

much sturdier than wind turbines. They

will be heavier and more expensive to

build, but will be able to capture more

energy.











	

 	

   	



	





	
 	
	 
	
				

Activity 1: Exploring Oil Seeps

Materials:

1 large clear glass

1 small mixing bowl

2 ml (milliliters) of cooking oil

10 cm3 (cubic centimeters) of sand

30 cm3 (cubic centimeters) of soil

1 piece of clay

water

Procedure:

1 Pour the sand into the bottom of the glass.

2 Pour the oil into the sand and add 1 ml of water.

3 Mix the soil with water until it is very wet, then pack

tightly into the glass.

4 Flatten the clay into a circle as large as the opening of

the glass.

5 Make a thin seal over the soil with the clay.

6 Fill the glass with water.

7 Observe the surface of the water to see how long it

takes the oil to seep through the layers to the top of

the water.

Results:

How long did it take for the oil to begin seeping to the top of the water?

Questions:

How long do you think it would take for all of the oil to seep to the top? How would you design

an experiment to determine this?

Would the oil seep faster if you constantly agitated the glass?

Would a taller glass with more water (more pressure) affect the rate of seepage?

What effect would using saltwater have?

	
	 
	
				 	



Activity 2: Drilling for Oil in the Ocean

Materials:

15 cm x 15 cm piece of foam board

4 sharpened pencils

2 clear plastic straws for each student

10-gallon aquarium

300 cm3 (cubic centimeters) of dark sand

1 large bag of light sand

clear tape

water

Procedure:

1 Pour the dark sand into the aquarium in

three equal mounds.

2 Cover the bottom of the aquarium and

the mounds of dark sand to a depth of

6 cm with light sand to resemble the

ocean floor.

3 Carefully fill the aquarium to a depth of

20 cm with water, taking care not to

disturb the sand.

4 Cut a 2 cm hole in the middle of the foam board.

5 Insert one sharpened pencil into each corner of the foam board, as legs for an oil rig.

6 Carefully place the rig in the water. The deck of the oil rig (foam board) should be

slightly above water level.

7 Tape two straws together end to end so that the juncture is completely sealed to make a

drill.

8 Try to strike oil by inserting your drill through the hole in the deck into the sand until it

hits the bottom of the aquarium. Cover the end of the straw tightly with one finger and

remove the straw.

Results:

Is there any dark sand in the end of the straw? Did you strike oil?

Research Questions:

How do geologists determine where to look for oil under the ocean?

What are the challenges of finding and producing oil from offshore basins?

What would life be like working on an offshore oil rig?

	
 	
	 
	
				

Activity 3: A Stationary Oil Rig

Background:

An oil rig is built on shore, then floated out to the drilling site on huge barges. In shallow water, a

rig rests on the ocean floor on long, hollow legs. While the rig is being towed to the site, the legs

are filled with air. Once the rig reaches the site, valves in the legs are opened and the legs slowly fill

with water, so that they sink to the bottom.

Materials:

10-gallon aquarium with water

15 cm x 15 cm piece of foam board

4 clear plastic straws

4 toothpicks

sharp knife

clay

Procedure:

1 Fill the aquarium with water to a depth of

15 cm.

2 Cut two 1-cm slits near the bottom of each

straw with a sharp knife. The slits will act as

water valves.

3 Make holes at the corners of the foam board

and insert the ends of the straws without the slits.

4 Seal both ends of the straws with clay. Mold the clay on the bottoms into 2 cm x 2 cm

square feet.

5 Float the platform in the aquarium.

6 Insert toothpicks in the slits in the straws to hold them open. (Opening the valves in the legs

of the rig).

7 Break the seal of the clay at the top of the straws so that the air in the straws can escape.

Results:

Describe the action of the rig as the straws filled with water.

Research Question:

What is the maximum depth of water in which a stationary rig could be used?
	
	 
	
				 	



Activity 4: A Floating Oil Rig

Background:

When drilling in deep water, a floating rig is used. Air-filled tanks (called ballast tanks) support the

rig, which is tethered to the bottom with cables.

Materials:

10-gallon aquarium with water

15 cm x 15 cm foam board

4 small empty glue bottles with twist-close tops

4 pieces of string or yarn 45 cm long

8 small weights such as sinkers

sharp knife

Procedure:

1 Fill the aquarium with water to a depth of 20 cm.

2 Make two small holes near the bottom of each glue

bottle.

3 Run a piece of string through the holes so that the

string is hanging evenly from each bottle.

4 Attach the weights to the ends of string.

5 Remove the tops from the glue bottles.

6 Make holes in the foam board big enough for the necks of the glue bottles. Insert the

bottles through the holes and replace the tops, closing them tightly.

7 Place the rig in the aquarium.

8 Spread out the weights on the bottom of the aquarium to secure the rig.

9 Adjust the water level in the aquarium if the weights don’t reach the bottom.

10 Open the tops of the glue bottles.

Results:

What happened when the tops of the glue bottles were opened?

Research Questions:

As more equipment is added to a floating rig, would you want more or less air in the ballast tanks?

What are some unique challenges to drilling in deep water?

		
 	
	 
	
				

Activity 5: Exploring Currents

Materials:

1 large glass beaker

2 ice cubes

4 drops of dark food coloring

1 bunsen burner with tripod, ring, and gauze mat

water

Procedure:

1 Fill the beaker with water and place on the ring.

2 Put the ice cubes into the water.

3 Heat the water very slowly with the bunsen burner.

4 Add food coloring very carefully to the top of the

water.

5 Observe the food coloring.

Results:

What happened to the food coloring?

Questions:

Which is denser—warm water or cold water?

How can you use this demonstration to explain

how ocean currents are driven by the sun?
	
	 
	
				 	




Activity 6: Exploring Wave Energy

Materials:

1 large deep pan

1 electric fan

1 drinking straw

1 piece of tissue paper (2 cm x 1/2 cm)

tape

water

Procedure:

1 Tape one end of the tissue paper to the

straw so that it hangs over one end of the straw.

2 Fill the pan to a depth of 2 cm with water.

3 Place the straw at an angle at one end of the pan, as shown in the diagram.

4 Use your hand to push the water in the pan into waves toward the straw.

5 Observe the tissue paper on the end of the straw.

6 Fill the pan almost to the top with water and remove the straw.

7 Turn on the fan and have it blow across the water.

8 Observe the top of the water.

Results:

What happened to the tissue paper on the end of the straw?

What effect did the fan have on the surface of the water?

Questions:

How can wave energy be harnessed using the concepts in this demonstration?

How does the sun produce wave energy?

	
 	
	 
	
				

Activity 7: Exploring Wind Energy

Materials:

1 unsharpened pencil with eraser

1 straight pin

1 piece of construction paper

scissors

electric fan

marker

Procedure:

1 Cut a 20 cm x 20 cm square of construction paper.

2 Fold the paper from corner to corner, then open and fold opposite corners. Flatten the

paper and mark the intersection with a dot.

3 Cut a little more than halfway up each crease.

4 Turn the paper over and place dots on the left points of each corner about 1 cm from the

ends.

5 Stick the straight pin through the dot of each point in turn, then through the center dot

and into the side of the pencil eraser. Make sure the pinwheel can spin freely on the

straight pin.

6 Use the fan to provide wind power for the pinwheels. Explore the relative speed of the

pinwheels at different distances from the fan and at different fan speeds.

Results:

How did the distance from the fan and the fan speed affect the rotation speed of the pinwheel?

Research Questions:

How do windmills produce electricity from wind power?

What are the advantages and disadvantages of wind machines?