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Course: NOVA Labs > Unit 1
Lesson 5: Energy- Growing appetites, limited resources
- Growing appetites, limited resources quiz
- Energy defined
- Energy defined quiz
- Putting energy to use
- Putting energy to use quiz
- Never-ending supply
- Never-ending supply quiz
- Solar power
- Solar power quiz
- Wind power
- Wind power quiz
- Solving the storage problem
- Solving the storage problem quiz
- Toward a smarter grid
- Toward a smarter grid quiz
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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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- 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? 0:50(11 votes)
- As far as I know of fossil fuels are not forming any more because when they originally formed the conditions were just right and they are not the correct conditions with today's climate.(2 votes)
- Why is it that co2 allows heat in but not out. How can it form a one-way layer like that?(4 votes)
- The transparent co2 lets the sunlight in, but when it is released back as infrared radiation the co2 absorbs it.(4 votes)
- Video does not specify oil barrel volume. Assuming standard 42 gallon barrels?(1 vote)
- Good assumption. Though it's not the unit used everywhere, the unit "oil barrel" ("bbl") is 42 gallons in the U.S. and Canada.
Source: I live near where this unit was standardized in 1866. =)
(I was not around at the time.)
...oh, and these:
http://aoghs.org/transportation/history-of-the-42-gallon-oil-barrel/
https://en.wikipedia.org/wiki/Barrel_(unit)#Oil_barrel(5 votes)
- 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) - - 1:06I want to help with the development of "large-scale alternatives." 1:15
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) - Reducing our carbon footprint is a great thing, however, wouldn't eliminating the number of feet do exponentially a greater good?(1 vote)
- 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)
- aren't there molecues that can interact with the co2 to stop it and make it helpful.(1 vote)
- the earth has ways of leveling everything out but humans are pumping co2 to fast to have the earth cool down. Also the earth might overheat and take thousands if not millions of years to cool down.(1 vote)
- Can we reduce the population to make things better?(1 vote)
- 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)
- Simply it causes global warming.
Anything which gets too much harms us.(0 votes)
- Isn't it possible for us humans to artificially develop coal and petroleum using the technology that we have today(1 vote)