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(5/8) De meest belangrijke video die je ooit zal zien (deel 5 van 8)

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that’s close enough to 500 to lie within the uncertainty of our knowledge of the size of the resource. So with that observation, that's a correct statement; at present rates, meaning zero growth, we have enough coal for 600 years. The whole point of the story that this lead into was a story about how we have to have major rapid growth in coal consumption in the U.S.. Well, it’s obvious isn’t it? If you have the growth that they’re writing about, it won’t last as long as they said it would last with zero growth. They never mentioned this. I wrote them a long letter, told them I thought it was a serious misrepresentation to give the readers the feeling we can have all this growth that they were writing about and still have coal around for 650 years. I got back a nice form letter; it had nothing to do with what I’d tried to explain to them. I gave this talk at a high school in Omaha, and after the talk, the high school physics teacher came to me, and he had a booklet. He said, “Have you seen this?” and I hadn't seen it; he said, “Look at this: ‘We've got coal coming out of our ears.’” As reported by Forbes magazine (that's a prominent business magazine), the United States has 437 billion tons of known coal reserves. That’s a good number; this is equivalent to a lot of BTUs or it’s “enough energy to keep 100 million large generating plants going for the next 800 yrs And the teacher said to me, “How can that be true? That’s one large electric generating plant for every two people in the United States!” I said, “Of course it can’t be true, it’s absolute nonsense. Let’s do long division to see how crazy it is.” So you take the coal they say is there, divide by what was then the current rate of consumption, you find you couldn’t keep that up for 800 years and we hardly at that time had 500 large electric plants —they said it would be good for a 100 million such plants. Time magazine tells us that “beneath the pit heads of Appalachia and the Ohio Valley, and under the sprawling strip mines of the west, lie coal seams rich enough to meet the country’s power needs for centuries, no matter how much energy consumption may grow.” So I give you a very fundamental observation: don't believe any prediction of the life expectancy of a non-renewable resource until you have confirmed the prediction by repeating the calculation. As a corollary, we have to note that the more optimistic the prediction, the greater is the probability that it’s based on faulty arithmetic or on no arithmetic at all. Again from Time magazine: “Energy industries agree that to achieve some form of energy self-sufficiency, the US must mine all the coal that it can.” Now think about that for just a moment. Let me paraphrase it: the more rapidly we consume our resources, the more self-sufficient we’ll be. Isn’t that what it says? David Brower called this the policy of “strength through exhaustion.” Here’s an example of strength through exhaustion: (Laughter) here is William Simon, energy advisor to the president of the United States. Simon says, “We should be trying to get as many holes drilled as possible to get the proven oil reserves.” The more rapidly we can get the last of that oil up out of the ground and finish using it, the better off we’ll be. So let’s look at Dr Hubbert’s graph for oil production in the lower 48 states, There was a long period of approximately steady growth indicated by this straight line on the semi logarithmic plot. For quite a while now production is fallen below the growth curve while our demand continue on up this growth curve until the 1970s It’s obvious the difference between the two curves has to be made up with imports. And it was in early 1995 that we read that the year 1994 was the first year in our nation’s history in which we had to import more oil than we were able to get out of our own ground. Well, maybe you’re wondering, does it make any sense to imagine that we can have steady growth in the rate of consumption of a resource till the last bit of it was used, then the rate of consumption would plunge abruptly to zero? I say no, that doesn't make sense. Okay, you say, why bother us with the calculation of this expiration time? My answer is this: every segment of our society, our business leaders, government leaders, political leaders, at the local level, state level, national level—every one aspires to maintain a society in which all measures of material consumption continue to grow steadily, year after year after year, world without end. Since that’s so central to every thing we do, we ought to know where it would lead. On the other hand, we should recognise there’s a better model and again we turn to the work of the late Dr Hubbert. He’s plotted the rate of consumption of resources that have already expired; he finds yes, there is an early period of steady growth in the rate of consumption. But then the rate goes through a maximum and comes back down in a nice symmetric bell-shaped curve. Now, when he did it, this curve to the data on US oil production back in the 1970s, he found at that point we were right there. We were halfway through that enormous resource. That’s roughly what that Texas expert said in a quotation we saw earlier. Now, let’s see what it means. It means that from now on, domestic oil production can only go downhill, and it’s downhill all the rest of the way, and it doesn’t matter what they say inside the beltway in Washington DC. Now, it means we can work hard and put some bumps on the downhill side of the curve; you’ll see there are bumps on the uphill side. The debate is heating up over drilling in the Arctic Wildlife Refuge. I’ve seen the estimate that they might find 3.2 billion barrels of oil up there. 3.2 billion is the area of that little tiny square; that’s less than one year’s consumption in the United States. So let’s look at the curve in this way: the area under the total curve, that represents the total resource in U. S. petroleum before any was used. It’s been divided into three parts, unshaded on the left: here is the oil we’ve taken from the ground: we’ve used it, it’s gone. This vertical shaded band, that’s the oil we’ve drilled into: we’ve found it, we’re pumping it today. Shaded in green on the right is the undiscovered oil. We have very good ways now of estimating how much oil remains undiscovered. This is the oil we’ve got to find if we’re going to make it down the curve on schedule. Now every once in a while somebody reminds me, that a hundred years ago, somebody did a calculation and predicted the U.S. would be out of oil in 25 years.” The calculation must’ve been wrong; therefore, of course, all calculations are wrong. Let’s understand what they did. One hundred years ago, this band of discovered oil was over in here somewhere. At that point they had no idea then how much oil was undiscovered. All they did was to take the discovered oil, divide it by how rapidly it was being used, and came up with 25 years. Well, it’s clear; you’ve got to make a new calculation every time you make a new discovery. We’re not asking today how long will the discovered oil last, we’re asking about the discovered and the undiscovered—we're now asking about the rest of the oil. And what does the US Geological Survey tell us? Back in 1984, they said the estimated US supply from undiscovered resources and demonstrated reserves was 36 years at present rates of production, or 19 years in the absence of imports. Five years later in 1989, that 36 years is down to 32 years, the 19 years is down to 16 years. So the numbers are holding together as we march down the right-hand side of the Hubbert curve. So maybe you wonder why didn't somebody tell us this. Well, back in 1956, Dr Hubbert addressed a convention of petroleum geologists and engineers. He told them that his calculations led him to conclude that “the peak of U.S. oil and gas production could be expected to occur between 1966 and 1971.” No one took him seriously. So let’s see what’s happened. The data here is from the Department of Energy. So, this is U.S. oil production. We see a long period of steady growth. Here is 1956, when Dr Hubbert did his analysis. He said at that time that peak would occur between 1966-1971. Well the peak occurred in1970. It was followed by a very rapid decline. Then the Alaskan pipeline started delivering its first oil, and it was a partial recovery. That production has now peaked and everything’s going downhill in unison. And when I go to a spreadsheet on my home computer and I find the parameters of the curve that’s the best fit to these scattered US data, from that best fit it looks to me as though we have consumed three quarters of the recoverable oil that was ever enough...

Video Details

Duration: 9 minutes and 28 seconds
Country: United States
Language: English
Views: 240
Posted by: ridelo on Jun 1, 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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