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Growing appetites, limited resources

Our ability to capture and convert energy into more usable forms has helped shape human society. Now we face a growing need for alternative energy sources and innovative technologies. Created by NOVA.

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  • leafers ultimate style avatar for user James Hulce
    At , the video states that while fossil fuels continue to form via natural processes, we are using them much faster than they are being created. What is the rate at which fossil fuels are forming today?
    (11 votes)
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  • aqualine seed style avatar for user Aman Vernekar
    Why is it that co2 allows heat in but not out. How can it form a one-way layer like that?
    (4 votes)
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  • piceratops ultimate style avatar for user trek
    Video does not specify oil barrel volume. Assuming standard 42 gallon barrels?
    (1 vote)
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  • female robot ada style avatar for user Katey Gordon
    Okay one question we know high rates of Co2 are in the air but couldn't we use Co2 and convert what is harmful into something useful?
    Could Co2 provide energy itself?
    (2 votes)
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  • leaf red style avatar for user aubrey
    - I want to help with the development of "large-scale alternatives."
    I find myself excited with the concepts of algae grown to make biodiesel, hydroelectric dams, solar farms, wind farms, underwater turbines powered by ocean currents, geothermal energy, hydrogen fuel cells. I think I want to be an engineer.
    I have a dilemma though: What kind of engineering is relevant?
    Petroleum, Electrical, Industrial, Civil, Environmental, Geotechnical, Geo-Environmental?
    Any helpful suggestions are appreciated!

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    You see, this video encourages me. "Here are our emerging energy problems," it seems to say to me. "We need to work on this."
    I feel invited to search for solutions. This stuff is serious and important. We need to be thinking about it. And we need to begin acting upon it. We can and will find solutions as long as people will work at the problems we face.

    So what about you? Are you willing to contribute to developing the large-scale energy alternatives that we need these days?
    (2 votes)
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  • leaf green style avatar for user Jake Orr
    Reducing our carbon footprint is a great thing, however, wouldn't eliminating the number of feet do exponentially a greater good?
    (1 vote)
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    • leaf blue style avatar for user x1
      If we cease all activities that produce carbon dioxide, we will die. If we cease all non-essential activities that produce carbon dioxide, we will be crippling ourselves technologically. Carbon dioxide waste is produced whenever we use combustion reactions for energy production, e.g. burning fossil fuels. All throughout human civilization, from automobiles to ore refineries to power plants, this activity is practiced and essential. Alternative energy sources are expensive to implement and maintain, and would require human consensus and investment. In order to have these, people need to be made aware of the benefits of alternative energy sources and be convinced to support leaders with good intentions, to empower them so that they can bring about the necessary change. The problem isn't figuring out what we need to do, the problem is in making the necessary changes, requiring us to overcome the economic and social grains resisting it.

      Both reducing the number of carbon waste producers, and how much they produce, would help reduce carbon dioxide waste. Ceasing all non-essential activities that produce carbon dioxide may not be beneficial due to new problems that arise because of the ceasing of these activities, but it is a more perfect solution to the carbon dioxide waste problem than reduction.
      (2 votes)
  • piceratops ultimate style avatar for user ET
    aren't there molecues that can interact with the co2 to stop it and make it helpful.
    (1 vote)
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  • hopper cool style avatar for user maceden
    What's the matter with carbon dioxide being released into the air? Doesn't the carbon dioxide help more trees and plants be able to grow and produce more oxygen?
    (2 votes)
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  • duskpin ultimate style avatar for user Aryan Kabra
    Isn't it possible for us humans to artificially develop coal and petroleum using the technology that we have today
    (1 vote)
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  • old spice man green style avatar for user Javon Martin
    Does anyone know how to measure the rate of carbon emissions in daily operations?
    Does anyone know how to measure the rate of gas exchange in plants?
    (0 votes)
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Video transcript