April 29, 2005

   (click photo for larger image)
Bay of Fundy

Energy III   

This is the THIRD of FIVE efforts to profile global energy issues and relate that to similar challenges with water, climate, and food.

In this issue

  • Neil deGrasse Tyson "Tug-of-War"
  • Energy - Oil & Water - read it now
  • Bay of Fundy photos - view them now
  • Tidal Power Plant - view it now
  • Paul Gipe - Wind Power - read now
  • Subscribe to KF News - sign up now
  • Send KF News to a friend - send now

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    Gravity in Reverse

    The following quotations are from an essay by, Neil deGrasse Tyson, Frederick P. Rose Director of the Hayden Planetarium. It was originally published in Natural History Magazine and reprinted in The Best American Science Writing 2004, Harper Collins 2004.

    He begins...
    "Cosmology has always been weird. Worlds resting on the backs of turtles, matter and energy coming into existence out of much less than thin air. And now, just when you'd gotten familiar, if not really comfortable, with the idea of a big bang, along comes something new to worry about. A mysterious and universal pressure pervades all of space and acts against the cosmic gravity that has tried to drag the universe back together ever since the big bang. On top of that, "negative gravity" has forced the expansion of the universe to accelerate exponentially, and cosmic gravity is losing the tug-of-war."

    And he concludes...
    "...Galaxies now visible will disappear beyond an unreachable horizon. In a trillion or so years, anyone alive in our own galaxy may know nothing of other galaxies. Our - or our alien Milky Way bretheren's - observable universe will merely comprise a system of nearby stars. Beyond the starry night will lie an endless void, without form: "darkness upon the face of the deep."

    I read this as an analogy for earth's predicament. Global population growth and expanding economies are stretching against the boundaries of natural systems that we have assumed would hold together indefinitely. Now, be it water, soil, endangered species, oil, the atmosphere, or food, they all seem caught in a "tug-of-war" and the glue, as we have known it, seems to be coming apart. Our challenge is here right now. What can individuals do to pull in the direction of balance? .

    Web Link - about Neil deGrasse Tyson

    I would like to point out that the same book, The Best American Science Writing 2004 also contains an essay by Michael Pollan, titled 'Cruising on the Ark of Taste' about the Slow Food Movement.

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    Global Energy

    It is good to get some things clear about "energy". The word, energy, refers to the capacity to do work. To get at how the word is used in media and conversation these days, it helps to distinguish between "capacity" in the form of a natural or manmade resources and "work" like, what work needs doing. A ready example is the resouce oil and the work of transportation. But it could also be water and electricity.

    The global issue with oil is transportation and thus gasoline consumption (oil's use for generating electric power is insignificant at 2%). On the other hand, the issue with electricity is burning the fossil fuel, coal to generate 55% of it (others include 23% nuclear, 12% hydro, 8% gas and 2% oil).


    The graph shows what the "big picture" of oil consumption looks like if seen in a 4000 year window. Obviously the intent is to dramatize the finite nature of oil as a resource. It is pretty well agreed among experts that we are at the peak of that graph right now as far as consumption of reserves is concerned. There may be widely varying opinions about what the down slope of the graph may look like.

    It took about 100 years to reach the peak of the graph and, if this picture is to be believed, it will take another 100 years to hit bottom. That doesn't sound immediately threatening until you look at the cost side of this picture

    This graph is about supply, not about price. A price graph (for the down side) may be an almost exact opposite. That graph would show that right now the price of oil is at the low starting point for the next 100 years.

    It is frequently said that when people feel the bite in their wallets they will get serious about gasoline conservation. That seems true. But the down slope of the graph may impact life styles beyond the gas pump. The globe depends on oil (gasoline) for food production, transportation, and the movement of consumer goods. As oil production tightens, all of these systems may be stressed. Frankly, if there were a sudden large shortage the only communities to be substantially unaffected would be Third World rural communities that still operate as closed local economies.

    Note: Today the state of Texas produces one quarter of the oil per day that it was producing in 1973.
    Perhaps technology will outpace the problem. It has happened before and the rewards here could be huge.

    I do believe that we are taking baby steps into the next world without really being aware of the end goal. By expanding on the following we can make a difference in years to come.

  • Expansion of local living economies which require minimal outside resourcing. (see LLE's at BALLE Alliance)
        Local food
        Local energy (wind, solar, hydro and other)
        Local transport
  • Expanded use of the Internet for business and pleasure
        Work from home flextime jobs
        Virtual vacations
  • Ride a bike and more?
        Pedestrianization of communities
        More parks
        More bikes
  • Co-op Housing - no less comfortable or personal
        More efficient and effective use of land, materials and energy
  • Water

    In addition to water being the basic sustaining fluid of life, it also has inherent power when in motion. Similar to wind, moving water tries to move things in its path and in so doing performs work. This power is harnessed and converted to electricity worldwide.

    In 2005 about 12% of electricity in the U.S. is produced by hydro power.

    What are the advantages of hydro electricity?

    "The "fuel" for hydro electricity is renewable and cheap. The only cost of hydro electricity are the expenses for building and maintaining the power stations and the dams. There are no costs for fuel or the transportation of such. The whole process is also environmentally friendly as it does not create any air, chemical, water or thermal pollution.

    What are the setbacks of hydro electricity?

    "Although hydro electricity has many advantages, there are still quite a few setbacks. The increase of water level might provide a better habitat for fish, but it could also destroy the habitat for humans and other species' by the flooding of land. Along with the disruption of natural orders, flooding also threatens historical landmarks found alongside the river system. In the case of the Three Gorges Dams Project in China, many historical sites, such as temples and castles were immersed with the water and 1.2 million people had to be moved."

    source: St. Mary's College - http://www.saintmarys.edu/~rtarara/ENERGY_PROJECT/hydro.htm
    Web Link - St. Mary's College - Energy Project

    "In the United States, it would be possible to produce 50 percent of total electricity through hydropower by the year 2100. In order for this to be possible, every available resource must be tapped. We would need to build 197 large dams (1000 MW) or 4300 small dams (50 MW), or 10,000 low head generators (25 MW), or a combination of three. This all costing 1 million dollars per megawatt. We would need 50,000 square miles of land to accomodate these plans. Overall, hydro power is a cheap, renewable, and efficient means of electricity. However, it is not likely that the United States will tap every available resource in the next 100 years."

    source: ORACLE ThinkQuest, Education Foundation - http://library.thinkquest.org/26366/text/alternative/hydro.html
    Web Link - ORACLE ThinkQuest, Education Foundation


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    More Water

    Bay of Fundy

    "The Bay of Fundy is located off the northern coast of Maine and extending 290-kilometers (180 miles) into Canada between New Brunswick and Nova Scotia. this natural phenomenon is home to 50-foot tides and so much more.  The mouth of the Bay is 100 km (62 miles) wide and between 120 and 215 meters (400-700 feet) deep. Frequently described as funnel-shaped, this amazing body of water gradually narrows until it splits to form Chignecto Bay and the Minas Basin."

    Every 12 hrs, 25 min. the a mass of water equal to the outflow of all the world's major rivers combined moves in a gradual churning motion . The highest tides on Earth occur in the Minas Basin, the eastern extremity of the Bay of Fundy, where the average tide range is 12 metres and can reach 16 metres when the various factors affecting the tides are in phase.

    "Although it is the gravitation of the Moon and Sun that raises the tides, the energy in the churning waters is extracted from the rotational energy of Earth spinning on its axis. Near Annapolis Royal, Nova Scotia, a tiny portion of this energy is being converted into commercial electrical energy in the only tidal power plant in the Western Hemisphere. The peak output of the Annapolis Basin generator is 20 megawatts, about 1% of Nova Scotia's electrical power capacity."

    Hopewell Rocks - the "Flower Pot" rocks - at high tide. These rocks serve as a popular marker to gauge the depth of the tidal surge.

    At Hopewell - looking east toward Nova Scotia at high tide.

    Hopewell Rocks - at low tide.

    At Hopewell - looking east toward Nova Scotia at low tide

    At Hopewell - looking south into Bay of Fundy at low tide

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    Annapolis Royal Tidal Power Plant - Bay of Fundy

    "This facility has the distinction of being the first and only modern tidal plant in North America. The station is located in Annapolis Royal by the Bay of Fundy, home of the world's highest tides. Twice a day, the tide comes in and out. Twice a day the turbine turns. Twice a day electricity is generated which is supplied to the provincial electric grid.

    "Annapolis uses the largest straflo turbine in the world to produce more than 30 million kilowatt hours per year - enough to power 4,000 homes.

    "Annapolis is one of three tidal power plants in the world. The largest plant is located in France, in the estuary of La Rance near St. Malo. With a capacity of 240 megawatts, it generates on the incoming and outgoing tide. The output capacity of Annapolis Tidal is 20 megawatts. The smallest tidal plant is located at Kislaya Guba on the White Sea in Russia. It has a 0.5 megawatt capacity."

    tidal power - http://www.calpoly.edu/~cm/studpage/nsmallco/clapper.htm
    Web Link - CalPoly student report

    Web Link - about Annapolis Royal

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    Paul Gipe

    quoted from his book
    Wind energy

    "The atmosphere is a huge, solar-fired engine that transfers heat from one part of the globe to another. Large-scale convection currents set in motion by the sun's rays carry heat from lower latitudes to northern climes. The rivers of air that pour across the surface of the earth in response to this global circulation are what we call wind. The working fluid in the atmospheric heat engine.

    "When the wind strikes an object, it exerts a force while attempting to move it out of the way. Some of the wind's kinetic energy is given up or transferred, causing the object to move. When it does, we say the wind has performed work. We can see this when leaves skid across the ground, trees sway, or the blades of a wind turbine move through the air.

    "While most wind-electric generation in North America is produced by giant wind power plants, this is not the case in northern Europe. Denmark's and Germany's experiences with wind energy are vastly different from that of North America.

    "Two-thirds of the wind-generated electricity in Denmark and Germany is produced by wind turbines in small groups or clusters. Many home owners, farmers, and small businesses in northern Europe operate their own medium-size wind turbine or share in the operation of a cooperatively owned group of turbines."

    George Beggs 4/2005 - Feedback is welcome

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