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(4/8) De meest belangrijke video die je ooit zal zien (deel 4 van 8)

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And the answer is, it’s one minute before 12:00. So we go one more decade to the turn of the century—that’s like right now—that’s when 7% would finish using up the oil reserves of the earth. So let's look at this in a very nice graphical way. Suppose the area of this tiny rectangle represents all the oil we used on this earth before 1940; then in the decade of the 40s, we used this much (uncovering part of chart): that's equal to all that had been used in all of history. In the decade of the 50s, we used this much (uncovering more of chart) : that's equal to all that had been used in all of history. In the decade of the 60s, we used this much (uncovering more of chart): again that's equal to the total of all the proceeding usage. Here we see graphically what President Carter told us. Now, if that 7% growth had continued through the 70s. 80s, and 90s, there's what we’d need (uncovering rest of chart). But that's all the oil there is. Now, there’s a widely held belief that if you throw enough money at holes in the ground, oil is sure to come up. Well, there will be discoveries in new oil; there may be major discoveries. But look: we would have to discover this much new oil if we would have that 7% growth continue ten more years. Ask yourself: what do you think is the chance that oil discovered after the close of our meeting today will be in an amount equal to the total of all we’ve known about in all of history? And then realise if all that new oil could be found, that would be sufficient to let the historic 7% growth continue ten more years. Well, it’s interesting to see what the experts say. Here’s from an interview in Time magazine, an interview with one of the most widely quoted oil experts in all of Texas. They asked him, “But haven’t many of our bigger fields been drilled nearly dry?” And he responds, saying “There’s still as much oil to be found in the US as has ever been produced.” Now, lets assume he’s right. What time is it? And the answer: one minute before 12:00. I’ve read several things this guy’s written; I don't think he has any understanding of this very simple arithmetic. Well, in the energy crisis about thirty years ago, we saw ads such as this (shows slide). This is from the American Electric Power Company. It’s a bit reassuring, sort of saying, now, don’t worry too much, because “we’re sitting on half of the world’s known supply of coal, enough for over 500 years.” Well, where did that “500 year” figure come from? It may have had its origin in this report to the committee on Interior and Insular Affairs of the United States Senate, because in that report we find this sentence: “At current levels of output and recovery, these American coal reserves can be expected to last more than 500 years.” There is one of the most dangerous statements in the literature. It’s dangerous because it’s true. It isn’t the truth that makes it dangerous, the danger lies in the fact that people take the sentence apart: they just say coal will last 500 years. They forget the caveat with which the sentence started. Now, what were those opening words? “At current levels.” What does that mean? That means if—and only if—we maintain zero growth of coal production. So let’s look at a few numbers. We go to the Annual Energy Review, published by the Department of Energy. They give this (pointing) as the coal demonstrated reserve base in the United States. It has a footnote that says “about half the demonstrated reserve base… is estimated to be recoverable.” You cannot recover —get out of the ground and use—100% of the coal that’s there. So this number is ½ of this number (pointing). We’ll come back to those in just a moment. The report also tells us that in 1971, we were mining coal at this rate, twenty years later at this rate (pointing). Put those numbers together, the average growth rate of coal production in that twenty years: 2.86% per year. And so we have to ask, well, how long would a resource last if you have steady growth in the rate of consumption until the last bit of it is used? I’ll show you the equation here for the expiration time. I’ll tell you it takes first year college calculus to derive that equation, so it can’t be very difficult. You know, I have a feeling there must be dozens of people in this country who’ve had first year college calculus, but let me suggest, I think that equation is probably the best-kept scientific secret of the century! Now, let me show you why. If you use that equation to calculate the life expectancy of the reserve base, or of the 1/2 they think is recoverable, for different steady rates of growth, you find if the growth rate is zero, the small estimate would go about 240 years and the large one would go close to 500 years. So that report to the Congress was correct. But look what we get if we plug in steady growth. Back in the 1970s, it was our national goal to achieve growth of coal production up around 8% per year. If you could achieve that and continue it, coal would last between 37 and 46 years. President Carter cut that goal roughly in half, hoping to reach 4% per year. If that could continue, coal would last between 59 and 75 years. Here’s that 2.86%, the average for the recent period of twenty years. If that could continue, coal would last between 72 and 94 years. That’s within the life expectancy of children born today. The only way you are going to get anywhere near this widely quoted 500 year figure, is to be able to do simultaneously two highly improbable things: number one, you’ve got to figure out how to use 100% of the coal that is in the ground; number two,you’ve got to figure out how to have 500 years of zero growth of coal production. Now these are simple facts. Just look at those numbers. I got a report recently from the Coalfield, Kentucky, West Virginia, Virginia these giant bituminous coalfields that supply a large fraction of the electricity in the Eastern United States. They have it made that maybe they have another 30 years of coalmining before it will become uneconomical to mine there. And then what will we do when we want to switch on the lights? Let's now go back and not that in 1970s, there was great national concern about energy. But these concerns disappeared in the 80s. Now, the concerns about energy in the 70s prompted experts, journalists, and scientists to assure the American people that there was no reason to be concerned. So let’s go back now and look at some of those assurances from the 70s so that we can see what to expect as the energy crisis returns. Here is the director of the energy division of the Oakridge National Laboratories. He's telling us how expensive it is to import oil, telling us we must have big increases in our use of coal. Under these conditions, he estimates, America’s coal reserves are so huge they can last “a minimum of 300 years, probably a maximum of 1000 years.” You’ve just seen the facts, now you see what an expert tells us, and what can you conclude? There was a three-hour television special on CBS on energy. The reporter said, “By the lowest estimate, we have enough (coal) for 200 years, by the highest, enough for more than 1000 years.” You’ve just seen the facts, now you can see what a journalist tells us after careful study, and what can you conclude? In the Journal of Chemical Education, on the page for high school chemistry teachers in an article by the scientific staff of the journal, they tell us our proven coal reserves are “enormous” and they give a figure: “these could satisfy present US energy needs for nearly 1000 years.” Well, let's do long division. You take the coal they say is there, divide by what was then the current rate of consumption, you get 180 years. Now they didn’t say “current rate of consumption,” they said “present US energy needs.” Coal today supplies about 1/5, about 20% of the energy we use in this country, so if you’d like to calculate how long this quantity of coal could satisfy present US energy needs, you have to multiply this denominator by five. When you do that you get 36 years. They said nearly 1000 years. Newsweek magazine, in a cover story on energy, said that at present rates of consumption, we have enough coal for 666.5 years—the point 5 means they think it’ll run out in July instead of January. (audience laughter) If you round that off, and say roughly 600 years, 600

Video Details

Duration: 9 minutes and 29 seconds
Country: United States
Language: English
Views: 293
Posted by: ridelo on May 31, 2011

Deze lezing door prof. Albert Bartlett toont het onvermogen van de mens aan om in te zien hoe beperkt onze aardse energiebronnen zijn. En de klok tikt...

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