If you follow the public debate over global warming, you get the impression that generating electricity is the only problem. Actually, electricity is the easy part of the problem because we can generate all the electricity we need from non-fossil energy sources. Considering the externalized costs of fossil fuels, the non-fossil sources are even cost-effective.
The hard part of the problem is motor fuels. We don't have a good substitute in place. Biofuels won't ever supply a major part of our motor fuels, for reasons we've discussed before. But take heart. Two chemists at Los Alamos National Laboratory have devised a process using current technology that could replace petroleum as as source. F. Jeffrey Martin and William L. Kubic have published Green Freedom: A Concept for Producing Carbon-Neutral Synthetic Fuels and Chemicals (Patent Pending).
A Simple Description
As you can imagine, turning atmospheric CO2 into gasoline takes a huge amount of energy. In this process, the energy inputs are in the form of heat and electricity. Lots of both.
The electricity could come from a number of sources, but the process is most effective if the electricity supply is steady, which effectively limits it to nuclear. That's just as well, though, because the CO2 capture requires spraying a potassium-carbonate solution into an air stream. That requires something very much like a wet cooling tower, so the wet cooling tower for the nuclear plant can do double duty as a CO2 collector.
Once the CO2 is collected, it can be extracted from the solution by an electrolytic process, originated by Martin and Kubic. They claim that this is their chief innovation and that all the other features of the process are standard to the chemical industry. The electrolytic process is more energy-efficient than other means of separating the CO2, and generates hydrogen at the same time, reducing the amount of hydrogen that has to be generated elsewhere.
In their baseline design, Martin and Kubic propose to use water electrolysis for generating the additional hydrogen needed. They chose this because nuclear plants in the US are all capable of providing the electricity needed. As they point out, more-recent technology can improve efficiencies substantially. Steam electrolysis consumes less energy and advanced nuclear reactors can generate hydrogen thermochemically; this last technique can be essentially 100% efficient, since the leftover heat can generate electricity.
Once the hydrogen is generated, commercially-tested processes can be used for converting CO2 and hydrogen into methanol, and for converting methanol into gasoline. Alternatively, hydrogen, CO2, and steam can be combined over catalysts in the Fisher-Tropsch process to produce any kind of hydrocarbon compound, including diesel oil and aviation fuel.
Practicality
As the authors take pains to make clear, the process depends only on equipment in commercial use today. There are no technological barriers to implementing it. There is a cost consideration, however. Their calculations show that the gasoline could be sold at the pump for $4.60 per gallon. Since we're dealing here with known technology they probably are not understating it by much, taking into account that projects of all kinds end up costing more than the planners expected.
But there are ample reasons for believing the actual costs would be lower. As they explain, newer technology will improve efficiencies considerably. Moreover, their analysis assumes their nuclear plant, which comprises the main capital cost, would be dedicated to producing hydrocarbon fuel. In practice, the nuclear plant will sell electricity during times of peak demand, especially when renewable energy is in short supply. This will become more apparent when fossil-fired power plants are phased out and all electricity depends on renewable and nuclear sources. We can look forward to an economy in which nuclear plants produce all our hydrocarbon fuels during off-peak hours. This sharing of costs will greatly reduce the cost of producing liquid fuels.
Looking Ahead
What we can say for sure is that it will take a massive energy investment to free the world from dependence on petrofuels. Straight hydrogen doesn't look promising because of the difficulty of onboard storage and because the inevitable leaks will threaten the ozone layer. Batteries for powering freight-hauling trucks don't seem like a reasonable hope, given the paltry improvements batteries have seen in the last few decades. Biofuels won't do the job, as discussed earlier. Since this process is already practical, it's not much of a stretch to predict that something very similar will be our fuel source in the future.
Monday, May 19, 2008
Saturday, April 26, 2008
Are Skeptics Right? Is the World Cooling?
This is one of those moments when one must suck it up and take a hard look at one's convictions. The data have been showing right along that greenhouse gases have been driving climate change during the last half-century or so. Nothing else could explain why the global-average temperature was rising while solar activity declined after 1990.
But then the climate gremlins struck. Skeptics believed themselves fully vindicated when temperature data showed the global-average temperature to have declined during the last five years, with a very sharp drop in the last year. Here are two plots that show the striking effect.
Since we are determined to follow the science where it goes, not where we want it to go, this startling development demanded a cold-blooded analysis, not defensive handwaving.
The puzzle gains difficulty when we look at the data for the northern and southern hemispheres separately, as shown here. The northern hemisphere is continuing to warm up while the southern hemisphere has cooled a surprising amount. Before we can proceed, we have to understand why the two hemispheres would be so dissimilar. In particular, the skeptics can't claim to be right unless they can explain why the northern hemisphere is warming.
As we look at the data for the two, we see that they agree only in broad strokes. When we look at them in detail, we see that there are notable differences. For example, the southern hemisphere was warming in the 1960s while the northern hemisphere was cooling.
That doesn't help us much to understand what's going on, though. What does help us is the explanation of la Niña events, as given here together with some surface-temperature data, given here. The data show the effects of la Niña events, in which stronger winds over the South Pacific cause ocean water to turn over, bringing cold water to the surface. That explains the cooler average surface temperature over the southern hemisphere. The average temperature seems to be headed down; what actually is happening is that the last el Niño event (a period of relative calm over the South Pacific) was fairly strong and the current la Niña event is especially strong, putting a kink in the curve. It is not the case that the world is cooling off; rather, warm water is being driven down to lower depths and colder water is being raised to the surface.
So that's where we stand. La Niña events explain why the southern hemisphere is showing a cooler average surface temperature. Only global warming due to greenhouse gases explains why the northern hemisphere is warming.
It seems reasonable that global warming could be causing the stronger and more-frequent la Niña events, but that's a question for experts.
But then the climate gremlins struck. Skeptics believed themselves fully vindicated when temperature data showed the global-average temperature to have declined during the last five years, with a very sharp drop in the last year. Here are two plots that show the striking effect.
Since we are determined to follow the science where it goes, not where we want it to go, this startling development demanded a cold-blooded analysis, not defensive handwaving.
The puzzle gains difficulty when we look at the data for the northern and southern hemispheres separately, as shown here. The northern hemisphere is continuing to warm up while the southern hemisphere has cooled a surprising amount. Before we can proceed, we have to understand why the two hemispheres would be so dissimilar. In particular, the skeptics can't claim to be right unless they can explain why the northern hemisphere is warming.
As we look at the data for the two, we see that they agree only in broad strokes. When we look at them in detail, we see that there are notable differences. For example, the southern hemisphere was warming in the 1960s while the northern hemisphere was cooling.
That doesn't help us much to understand what's going on, though. What does help us is the explanation of la Niña events, as given here together with some surface-temperature data, given here. The data show the effects of la Niña events, in which stronger winds over the South Pacific cause ocean water to turn over, bringing cold water to the surface. That explains the cooler average surface temperature over the southern hemisphere. The average temperature seems to be headed down; what actually is happening is that the last el Niño event (a period of relative calm over the South Pacific) was fairly strong and the current la Niña event is especially strong, putting a kink in the curve. It is not the case that the world is cooling off; rather, warm water is being driven down to lower depths and colder water is being raised to the surface.
So that's where we stand. La Niña events explain why the southern hemisphere is showing a cooler average surface temperature. Only global warming due to greenhouse gases explains why the northern hemisphere is warming.
It seems reasonable that global warming could be causing the stronger and more-frequent la Niña events, but that's a question for experts.
Monday, April 21, 2008
A Skeptic with a Degree
This article is a review of the book, Climate Confusion: How Global Warming Hysteria Leads to Bad Science, Pandering Politicians and Misguided Policies that Hurt the Poor, by Roy W. Spencer.
According to the dust jacket, Dr. Spencer holds a PhD in Meteorology and is a Principal Research Scientist in Climate Science at the University of Alabama. His expressed skepticism about human-caused climate change would, therefore, seem to be the clearest possible vindication of the skeptics' view on that topic.
Since Dr. Spencer is a professional scientist writing about his own specialty, one would expect any book he writes to be jammed with scientific information about this complex subject. But one would be disappointed. In fact, his scientific coverage extends over two pages, from page 80 to 82. In this short passage, he sums up the knowledge about climate change thus:
"First, we know that mankind is producing carbon dioxide as a result of our use of a wide variety of fuels, from coal and petroleum to natural gas and wood."
"A second observation we are certain of is that the carbon dioxide content of the global atmosphere has been slowly increasing. We are now about 40 percent of the way to a doubling of the pre-industrial concentrations of atmospheric carbon dioxide."
"Thirdly, we know that carbon dioxide is a greenhouse gas, which means that it traps infrared radiation and so tries to warm the lower troposphere to a higher temperature than if the gas was not there."
"Finally, we are pretty sure that the globally averaged surface temperature of the Earth is at least 1° Fahrenheit warmer now than it was about a century ago."
This is as clear a proof of climate change as could be imagined. Yet, Dr. Spencer demurs from stating the natural and obvious conclusion. Why, you may wonder. He says that he's withholding his conclusion because temperature rise and CO2 concentration rise might occur together only by coincidence. That is, global warming might be due to natural variability.
Natural variability is outside our experience with thermodynamic systems. We know why car engines warm up; it's because of fuel being burned. We know why houses warm up; it's either because the sun is beating on them or because of their furnaces. Our bodies warm up because we're exercising muscles or because the temperature control mechanisms are impaired by illness. But Dr. Spencer thinks it is realistically possible that Earth could just naturally change temperature without any cause. And that possibility prevents him from accepting the prevailing scientific view.
After seeing the subtitle of the book, though, one might wonder if that really is the reason. The other 180 pages could have been transcripted straight from hate-talk shows on AM radio. Environmentalists put the needs of wildlife above those of humans. Governments and philanthropic foundations reward and punish scientists according to their positions on climate change. Europeans prospered 1000 years ago because of unusually-warm conditions. People overreact when cities are wiped out by hurricanes. Scientists don't know as much as they think they do. Global warming is a religion. Politicians are using it as a trick for taking money away from working people. Scientists are milking it like a cow. Reducing emissions will harm the economy. The Precautionary Principle is wrong. Global warming is good for poor people. Left wingers killed millions of people by banning DDT. The United Nations works to make everybody poor.
Why is all this right-wing propaganda in a book written by a scientist? Since it takes up the largest part of the book by far, we can in all fairness ask if Dr. Spencer's skepticism is really due to scientific rigor or if his political views have overcome his objectivity.
According to the dust jacket, Dr. Spencer holds a PhD in Meteorology and is a Principal Research Scientist in Climate Science at the University of Alabama. His expressed skepticism about human-caused climate change would, therefore, seem to be the clearest possible vindication of the skeptics' view on that topic.
Since Dr. Spencer is a professional scientist writing about his own specialty, one would expect any book he writes to be jammed with scientific information about this complex subject. But one would be disappointed. In fact, his scientific coverage extends over two pages, from page 80 to 82. In this short passage, he sums up the knowledge about climate change thus:
"First, we know that mankind is producing carbon dioxide as a result of our use of a wide variety of fuels, from coal and petroleum to natural gas and wood."
"A second observation we are certain of is that the carbon dioxide content of the global atmosphere has been slowly increasing. We are now about 40 percent of the way to a doubling of the pre-industrial concentrations of atmospheric carbon dioxide."
"Thirdly, we know that carbon dioxide is a greenhouse gas, which means that it traps infrared radiation and so tries to warm the lower troposphere to a higher temperature than if the gas was not there."
"Finally, we are pretty sure that the globally averaged surface temperature of the Earth is at least 1° Fahrenheit warmer now than it was about a century ago."
This is as clear a proof of climate change as could be imagined. Yet, Dr. Spencer demurs from stating the natural and obvious conclusion. Why, you may wonder. He says that he's withholding his conclusion because temperature rise and CO2 concentration rise might occur together only by coincidence. That is, global warming might be due to natural variability.
Natural variability is outside our experience with thermodynamic systems. We know why car engines warm up; it's because of fuel being burned. We know why houses warm up; it's either because the sun is beating on them or because of their furnaces. Our bodies warm up because we're exercising muscles or because the temperature control mechanisms are impaired by illness. But Dr. Spencer thinks it is realistically possible that Earth could just naturally change temperature without any cause. And that possibility prevents him from accepting the prevailing scientific view.
After seeing the subtitle of the book, though, one might wonder if that really is the reason. The other 180 pages could have been transcripted straight from hate-talk shows on AM radio. Environmentalists put the needs of wildlife above those of humans. Governments and philanthropic foundations reward and punish scientists according to their positions on climate change. Europeans prospered 1000 years ago because of unusually-warm conditions. People overreact when cities are wiped out by hurricanes. Scientists don't know as much as they think they do. Global warming is a religion. Politicians are using it as a trick for taking money away from working people. Scientists are milking it like a cow. Reducing emissions will harm the economy. The Precautionary Principle is wrong. Global warming is good for poor people. Left wingers killed millions of people by banning DDT. The United Nations works to make everybody poor.
Why is all this right-wing propaganda in a book written by a scientist? Since it takes up the largest part of the book by far, we can in all fairness ask if Dr. Spencer's skepticism is really due to scientific rigor or if his political views have overcome his objectivity.
Sunday, March 16, 2008
Tipping Points
With Speed and Violence: Why Scientists Fear Tipping Points in Climate Change by Fred Pearce is not reassuring or comfortable. It is a scientifically-grounded explanation of climate change/global warming/freaky world changes.
It probably could only have been written by Mr. Pearce. He's been following the global-warming story as a journalist since about 1990 and because of that he was able to interview many of the principal researchers in the ongoing struggle to understand the process.
He presents four topics of interest. First, he explains the mechanics of climate change. If you're a little fuzzy on the ocean conveyor or methane clathrates he'll bring you up to speed. Second, he lays out the limits of knowledge. The parameters cover large ranges and he keeps clear the distinction between what is known and what isn't. Third, he covers the slipperiest part of the whole topic: tipping points; how they work and what happens when we reach them. He also discusses what the consequences of climate change are likely to be, bearing in mind the limits of certainty. We're going to say a little here about tipping points, based on the author's remarks.
Skeptics dismiss the concept of tipping points. You can't prove them, they say. Actually, you can prove some of them but it's not clear what will activate them. Some others aren't understood to the point they can be considered certain. It goes the other way too, though. There's no justification for traveling up the Keeling curve with insouciance. Before we jump into a pot of hot tar, common sense tells us we ought to find out how hot the tar is.
I'll go through the main tipping points the author describes.
The author makes the point that this issue is different from the issues we're used to. Usually, when you learn more about a concern you find that it's not as alarming as you thought before. With global warming, the more you learn the more there is to worry about.
It probably could only have been written by Mr. Pearce. He's been following the global-warming story as a journalist since about 1990 and because of that he was able to interview many of the principal researchers in the ongoing struggle to understand the process.
He presents four topics of interest. First, he explains the mechanics of climate change. If you're a little fuzzy on the ocean conveyor or methane clathrates he'll bring you up to speed. Second, he lays out the limits of knowledge. The parameters cover large ranges and he keeps clear the distinction between what is known and what isn't. Third, he covers the slipperiest part of the whole topic: tipping points; how they work and what happens when we reach them. He also discusses what the consequences of climate change are likely to be, bearing in mind the limits of certainty. We're going to say a little here about tipping points, based on the author's remarks.
Skeptics dismiss the concept of tipping points. You can't prove them, they say. Actually, you can prove some of them but it's not clear what will activate them. Some others aren't understood to the point they can be considered certain. It goes the other way too, though. There's no justification for traveling up the Keeling curve with insouciance. Before we jump into a pot of hot tar, common sense tells us we ought to find out how hot the tar is.
I'll go through the main tipping points the author describes.
* Shrinking ice caps. This one is maybe the most basic. As the ice caps shrink the world is absorbing more energy from the sun. Furthermore, the water released lubricates the glaciers' movements, causing the process to accelerate.
* Clearing of rain forests lowers the amount of rainfall downwind from them, whether it's done on purpose or by natural fires that result from drying out. As the vegetation burns and exposes the soil to sunlight, large amounts of CO2 are released.
* As frozen bogs thaw in the extreme north, rotting tundra releases methane, a terribly effective greenhouse gas.
* CO2 dissolved in the oceans is removed by marine organisms that use it to build structural body parts. If the CO2 level rises too high, ocean water becomes too acidic for the organisms to live and this CO2-removal mechanism disappears.
* Clathrates are layers of methane lying in deep ocean trenches where the pressure and temperature are extreme enough to keep them frozen. If ocean temperatures rise enough to thaw some of the methane then inevitably it will enter the atmosphere. But it could be worse: there are layers of methane gas under the clathrates, kept unfrozen by warmth from the earth. If the ocean melts through spots in the clathrates, large amounts of methane will escape.
* Clouds are a subject of considerable uncertainty. As water evaporates we expect to see more white, fluffy clouds that reflect solar energy. That may be why the world hasn't warmed more than it has. But if the atmosphere gets hot enough we'll see fewer fluffy clouds and more high, thin clouds. They admit more solar energy and intercept energy that otherwise would escape.
* The ocean conveyor is a superlong ocean current; one of the things it does is carry heat from the tropics to the north Atlantic, warming the US coast before it swings over and does the same for northern Europe. As it moves north to the Arctic region it cools and drops down to return under the north-moving stream. What if Greenland's ice melts? If it happens fast enough, a real possibility, the fresh water would cause the saltier and heavier water of the current to short-circuit; it would drop down to the return stream prematurely. Northern Europe would see severely cold conditions. Meanwhile, the tropics would warm up because of losing the Arctic cooling.
The author makes the point that this issue is different from the issues we're used to. Usually, when you learn more about a concern you find that it's not as alarming as you thought before. With global warming, the more you learn the more there is to worry about.
Saturday, March 8, 2008
US Presidential Candidates on Global Warming
Here we offer a comparison of the views of the three major contenders for US President with respect to global warming.
Senator John McCain
Senator McCain has co-sponsored, with Senator Lieberman, legislation that would establish cap-and-trade measures for dealing with greenhouse-gas emissions. He tends to favor technological solutions over behavioral changes. In line with that view he supports federal support for nuclear energy.
Of the three candidates, he may have the most realistic views. At a time when millions of people are driving motor homes, yachts, and private aircraft around for recreation, buying houses bigger than they can afford, and treating flying vacations as a divinely-ordained right, perhaps it's too idealistic to suppose the greatest number would give up such indulgences.
As advocates of nuclear energy, we applaud his support for that technology. On the other hand, the view here is that what the country needs are coherent energy and environmental policies. If fossil fuels weren't subsidized with tax credits and if air-quality standards were reasonable, utilities would pursue nuclear and renewable energy without any federal support. Besides, nukes can't do the whole job, not even with cap-and-trade. The country needs some serious leadership on conservation as well.
Senator Hillary Clinton
Senator Clinton offers what looks more like a wish list than a plan. Cap-and-trade, R&D and subsidies for renewable energy, higher efficiency standards, and something called "home-grown biofuels." In the past she has said nuclear energy has to be kept on the table, but such sentiments don't appear on her website.
From here it looks as though she (or whatever staffer writes her energy positions) doesn't grasp the magnitude of the challenge or the urgency. Perhaps she knows better but doesn't want to offend the bicycling-and-winetasting crowd. We can sympathize, but it's not a point in her favor.
Senator Barack Obama
Senator Obama's positions are so close to Senator Clinton's it's hard to tell them apart. Possibly, the main difference is that he sets out his policies in more detail, so they come together as a plan. He understands the importance of setting stricter clean-air standards. He understands the value and the limitations of renewable energy sources, including biofuels.
He recognizes the importance of nuclear energy, but sets out four issues that must be addressed: public right-to-know, security of nuclear fuel and waste, waste storage, and proliferation. Then he proceeds to describe the measures he will take to address these same four issues. As advocates of nuclear energy, we are convinced that these issues have been addressed successfully and that any administration that looks at them clearly will work hard to develop nuclear energy.
Conclusions
Senator Obama seems to have the most comprehensive plan for dealing with global warming. Senator Clinton's might be as comprehensive, or possibly could be identical, but she doesn't spell it out and she doesn't mention nuclear energy; that's a major omission. Senator McCain is pro-nuclear; that's good but it's not enough.
It's appropriate to point out here the main problems with cap-and-trade, since it's the most important feature in all three candidates' positions. First, there's the ethical problem of letting polluters decide the price of pollution rights. Surely the victims ought to be setting the price. Second there's this political problem: call it what you like, cap-and-trade is a tax. Republicans won't allow it. Democratic politicians facing tough challenges won't vote for it. That means we have to weigh the different plans discounting the cap-and-trade part or any part that depends on it.
If we weigh the plans this way, Sen. McCain has only support for nuclear energy and Sen. Clinton has good intentions. Sen. Obama still has a plan.
Senator John McCain
Senator McCain has co-sponsored, with Senator Lieberman, legislation that would establish cap-and-trade measures for dealing with greenhouse-gas emissions. He tends to favor technological solutions over behavioral changes. In line with that view he supports federal support for nuclear energy.
Of the three candidates, he may have the most realistic views. At a time when millions of people are driving motor homes, yachts, and private aircraft around for recreation, buying houses bigger than they can afford, and treating flying vacations as a divinely-ordained right, perhaps it's too idealistic to suppose the greatest number would give up such indulgences.
As advocates of nuclear energy, we applaud his support for that technology. On the other hand, the view here is that what the country needs are coherent energy and environmental policies. If fossil fuels weren't subsidized with tax credits and if air-quality standards were reasonable, utilities would pursue nuclear and renewable energy without any federal support. Besides, nukes can't do the whole job, not even with cap-and-trade. The country needs some serious leadership on conservation as well.
Senator Hillary Clinton
Senator Clinton offers what looks more like a wish list than a plan. Cap-and-trade, R&D and subsidies for renewable energy, higher efficiency standards, and something called "home-grown biofuels." In the past she has said nuclear energy has to be kept on the table, but such sentiments don't appear on her website.
From here it looks as though she (or whatever staffer writes her energy positions) doesn't grasp the magnitude of the challenge or the urgency. Perhaps she knows better but doesn't want to offend the bicycling-and-winetasting crowd. We can sympathize, but it's not a point in her favor.
Senator Barack Obama
Senator Obama's positions are so close to Senator Clinton's it's hard to tell them apart. Possibly, the main difference is that he sets out his policies in more detail, so they come together as a plan. He understands the importance of setting stricter clean-air standards. He understands the value and the limitations of renewable energy sources, including biofuels.
He recognizes the importance of nuclear energy, but sets out four issues that must be addressed: public right-to-know, security of nuclear fuel and waste, waste storage, and proliferation. Then he proceeds to describe the measures he will take to address these same four issues. As advocates of nuclear energy, we are convinced that these issues have been addressed successfully and that any administration that looks at them clearly will work hard to develop nuclear energy.
Conclusions
Senator Obama seems to have the most comprehensive plan for dealing with global warming. Senator Clinton's might be as comprehensive, or possibly could be identical, but she doesn't spell it out and she doesn't mention nuclear energy; that's a major omission. Senator McCain is pro-nuclear; that's good but it's not enough.
It's appropriate to point out here the main problems with cap-and-trade, since it's the most important feature in all three candidates' positions. First, there's the ethical problem of letting polluters decide the price of pollution rights. Surely the victims ought to be setting the price. Second there's this political problem: call it what you like, cap-and-trade is a tax. Republicans won't allow it. Democratic politicians facing tough challenges won't vote for it. That means we have to weigh the different plans discounting the cap-and-trade part or any part that depends on it.
If we weigh the plans this way, Sen. McCain has only support for nuclear energy and Sen. Clinton has good intentions. Sen. Obama still has a plan.
Monday, March 3, 2008
How to Solve the United States' Worst Economic and Environmental Problems
First, the main economic problem is reduced job opportunities. As manufacturing jobs leave the country, middle Americans are watching their job opportunities shrink. They move to poorer-paying jobs that contribute less to society. Instead of providing goods and services that benefit other people, they sell goods and services provided by others. Junk-mail advertising, telephone soliciting, clerking in big-box stores. Data entry work for marketing companies. A nation of people taking in each other's laundry. Or selling each other long-distance phone service.
This problem is compounded by competition from immigrants from countries where people have even fewer opportunities. In this regard, the only plausible solution is for other countries to solve their own economic problems, for which this article is a template.
The second problem is too much cash floating around. Credit has been so easy to acquire that people have reached the saturation point with stuff, even buying houses they can't afford. Furniture, appliances, electronics, sports gear---how much stuff can a person own? The first time a cold economic wind blows, everyone stops shopping. Of course. It's time to conserve cash and pay down debts. Our federal government has come up with an economic stimulus plan so absurd it sounds like a joke. The government will borrow billions of dollars and dole it out to people in the hope they'll spend it on things they don't need. President Bush's biggest fear is that people will behave intelligently and do otherwise.
Now let's look at the environmental problems. Fossil fuels account for nearly all the air-pollution problems and a big part of the water-pollution problems. Even outweighing those is climate change caused mainly by burning fossil fuels.
As the other articles in this blog have shown, the most important solution to these problems is to convert from fossil fuels to renewables, especially windpower, and nuclear energy. What are the barriers to improving this situation? You saw this coming, didn't you? First, there aren't enough trained workers. Second, it takes a lot of capital investment.
So we see that the solution to our environmental problems is also the solution to our economic problems. When people go to work manufacturing the equipment for renewable and nuclear energy sources, or constructing the facilities, they can earn good pay because these are highly productive jobs with a big economic payback. Furthermore, and for the same reason, these are splendid investment opportunities. With the low interest rates presently being paid on investments and the low interest rates charged to borrowers, people have little incentive to save. But given this excellent investment opportunity, people can direct their earnings toward long-term financial security.
Is this sleight of hand? Voodoo economics? Not at all. It's simply the transfer of money away from wasteful consumerism toward long-term investment. It will transform the country in magnificent ways but it's not a magic trick.
The economic pressure driving this change is so powerful it won't be contained; the only point in question is how long it will take to start it. My opinion is that the only thing holding it back is an administration that believes consumerism is the sole engine of wealth. If I'm right, then next January we'll see the beginning of an avalanche of economic drive. All three of the leading candidates understand that prosperity depends on growth, not on spending.
Get ready and hold on.
This problem is compounded by competition from immigrants from countries where people have even fewer opportunities. In this regard, the only plausible solution is for other countries to solve their own economic problems, for which this article is a template.
The second problem is too much cash floating around. Credit has been so easy to acquire that people have reached the saturation point with stuff, even buying houses they can't afford. Furniture, appliances, electronics, sports gear---how much stuff can a person own? The first time a cold economic wind blows, everyone stops shopping. Of course. It's time to conserve cash and pay down debts. Our federal government has come up with an economic stimulus plan so absurd it sounds like a joke. The government will borrow billions of dollars and dole it out to people in the hope they'll spend it on things they don't need. President Bush's biggest fear is that people will behave intelligently and do otherwise.
Now let's look at the environmental problems. Fossil fuels account for nearly all the air-pollution problems and a big part of the water-pollution problems. Even outweighing those is climate change caused mainly by burning fossil fuels.
As the other articles in this blog have shown, the most important solution to these problems is to convert from fossil fuels to renewables, especially windpower, and nuclear energy. What are the barriers to improving this situation? You saw this coming, didn't you? First, there aren't enough trained workers. Second, it takes a lot of capital investment.
So we see that the solution to our environmental problems is also the solution to our economic problems. When people go to work manufacturing the equipment for renewable and nuclear energy sources, or constructing the facilities, they can earn good pay because these are highly productive jobs with a big economic payback. Furthermore, and for the same reason, these are splendid investment opportunities. With the low interest rates presently being paid on investments and the low interest rates charged to borrowers, people have little incentive to save. But given this excellent investment opportunity, people can direct their earnings toward long-term financial security.
Is this sleight of hand? Voodoo economics? Not at all. It's simply the transfer of money away from wasteful consumerism toward long-term investment. It will transform the country in magnificent ways but it's not a magic trick.
The economic pressure driving this change is so powerful it won't be contained; the only point in question is how long it will take to start it. My opinion is that the only thing holding it back is an administration that believes consumerism is the sole engine of wealth. If I'm right, then next January we'll see the beginning of an avalanche of economic drive. All three of the leading candidates understand that prosperity depends on growth, not on spending.
Get ready and hold on.
Monday, February 11, 2008
Construction Times for Nuclear Power Plants
I had thought we were pretty much done but the kids in the basement came up with another reason why we can't use nuclear energy. Nukes take too long to build! they whined, their lips quivering. It took ten years to build them before. Jim Hansen at NASA says we only have ten years to stop all the greenhouse gases or we're gonna die! We'll build windmills instead.
Now, how could anyone know all that? The estimable Dr. Hansen actually says
Dr. Hansen goes on to make concrete suggestions, such as a cessation of building new fossil-fired power plants. He offers the possibility that in ten years it might be necessary to bulldoze all the existing ones.
Actually, a better plan would be to replace all the boilers with nuclear reactors. Most of the construction cost and effort is in the generating portion of the plant, anyway, so replacing the boilers will be much cheaper and faster than building new nuclear plants from scratch.
His other recommendations, such as financial incentives and improving the efficiency of buildings and vehicles, agree with the views of just about everyone who's looked at the issue.
But besides oversimplifying Dr. Hansen's remark, the kids are presuming to know more than they do.
We don't know how long it will take to build nuclear plants. In Japan they can build them in less than five years. If other countries got serious and cranked up their capacities for building them they could do it even faster.
The new designs are simpler than the earlier designs. The designers have incorporated features into them that make them inherently safer so that the risk of accident is lower even while the safety systems are less complex. Furthermore, manufacturing and construction technology has advanced in the last few decades. Just as office buildings can be put up faster and cheaper, so can power-plant structures. Computers and laser-guided machine tools have revolutionized the manufacture of heavy machinery. New testing techniques ensure quality control both cheaper and more thorough.
Besides, wind farms take more construction effort than nukes. Consider that a 1000 MW nuke will average over 850,000 KW. A very big (rotor-tip height ~ 450 feet!) wind turbine rated at 1.5 MW will average less than 500 KW. So 1 nuke equals more than 1700 big turbines.
As luck would have it, the British House of Lords studied the question and compiled some comparative data (and you wondered what the lords did!). A good measure of the construction effort is the energy inputs required for manufacturing and construction. What they show is that a 1000 MW nuke takes 6280 terrajoules per average GW, while a 25 MW wind farm takes 20,575, more than three times as much.
This is not an energy comparison, because that's much more complicated. We're only using these numbers to represent the manufacturing and construction effort.
What it shows is that the kids got it wrong. Again. Even if wind could provide full-time power, it still couldn't outpace nuclear in converting away from fossil fuels.
Now, how could anyone know all that? The estimable Dr. Hansen actually says
"The Energy Department says that we're going to continue to put more and more CO2 in the atmosphere each year--not just additional CO2 but more than we put in the year before. If we do follow that path, even for another ten years, it guarantees that we will have dramatic climate changes that produce what I would call a different planet--one without sea ice in the Arctic; with worldwide, repeated coastal tragedies associated with storms and a continuously rising sea level; and with regional disruptions due to freshwater shortages and shifting climatic zones."
Dr. Hansen goes on to make concrete suggestions, such as a cessation of building new fossil-fired power plants. He offers the possibility that in ten years it might be necessary to bulldoze all the existing ones.
Actually, a better plan would be to replace all the boilers with nuclear reactors. Most of the construction cost and effort is in the generating portion of the plant, anyway, so replacing the boilers will be much cheaper and faster than building new nuclear plants from scratch.
His other recommendations, such as financial incentives and improving the efficiency of buildings and vehicles, agree with the views of just about everyone who's looked at the issue.
But besides oversimplifying Dr. Hansen's remark, the kids are presuming to know more than they do.
We don't know how long it will take to build nuclear plants. In Japan they can build them in less than five years. If other countries got serious and cranked up their capacities for building them they could do it even faster.
The new designs are simpler than the earlier designs. The designers have incorporated features into them that make them inherently safer so that the risk of accident is lower even while the safety systems are less complex. Furthermore, manufacturing and construction technology has advanced in the last few decades. Just as office buildings can be put up faster and cheaper, so can power-plant structures. Computers and laser-guided machine tools have revolutionized the manufacture of heavy machinery. New testing techniques ensure quality control both cheaper and more thorough.
Besides, wind farms take more construction effort than nukes. Consider that a 1000 MW nuke will average over 850,000 KW. A very big (rotor-tip height ~ 450 feet!) wind turbine rated at 1.5 MW will average less than 500 KW. So 1 nuke equals more than 1700 big turbines.
As luck would have it, the British House of Lords studied the question and compiled some comparative data (and you wondered what the lords did!). A good measure of the construction effort is the energy inputs required for manufacturing and construction. What they show is that a 1000 MW nuke takes 6280 terrajoules per average GW, while a 25 MW wind farm takes 20,575, more than three times as much.
This is not an energy comparison, because that's much more complicated. We're only using these numbers to represent the manufacturing and construction effort.
What it shows is that the kids got it wrong. Again. Even if wind could provide full-time power, it still couldn't outpace nuclear in converting away from fossil fuels.
Sunday, February 10, 2008
The Linear-No-Threshold Hypothesis
In a recent article we discussed the BEIR VII report's conclusion with respect to the linear-no-threshold (LNT) hypothesis concerning low-level radiation's possible health effects. It's worthwhile to compare it with other reports' findings, all from professional organizations in the US.
First, here's the pertinent statement in BEIR VII
That's a tepid justification for retaining LNT, but compare that with the statement from the National Institutes of Health:
And with the statement from the Health Physics Society"
Professor Bernard Cohen goes on to estimate what would be the health effects of low-level exposures and compares them with other health risks, using the LNT model even though he shows in his analyses that it overstates the adverse effects and probably understates the beneficial (hormesis) effects of low-level radiation.
As an exercise we'll do something simple here. The BEIR report says ten million mSv would cause 1140 deaths. And it says that, on average, 304 million Americans receive 3 mSv per year, so the total would be 912 million mSv. So all of the radiation-induced deaths add up to 104,000 per year. Of that number, according to the report, 0.2% are due to nuclear energy, the rest mainly being due to natural radiation. If the LNT hypothesis is right, 208 deaths per year can be attributed to nuclear energy.
In comparison, every study done shows that tens of thousands of Americans die every year from the pollution generated by coal-fired power plants. The most comprehensive study done so far puts the range between 33,000 and 121,000 per year, just counting adults over 25. In 2006, according to DOE, coal generated 1930 billion KWH of electricity and nuclear generated 787 billion KWH, so if nuclear replaced coal an additional 510 deaths would take place, but at least 50,000 lives would be saved.
And all of the radiation-related deaths depend on a hypothesis that hasn't been proved and which specialized professionals don't believe.
Here's the kicker: Coal plants emit more than ten times as much radioactivity as nuclear power plants. If the LNT hypothesis were true, 5000 of the coal-related deaths would be avoided by converting to nuclear energy just because of reducing radioactive emissions.
If some form of renewable energy could provide full-time power, this might be a harder decision to make. As we saw in an earlier article, though, there aren't any that could.
So those are the two options. We can let over 50,000 Americans die every year from coal or we can switch to nuclear energy and start cleaning up the environment while minimizing the threat of global warming. What to do, what to do.
First, here's the pertinent statement in BEIR VII
"At doses of 100 mSv or less, statistical limitations make it difficult to evaluate cancer risk in humans. A comprehensive review of available biological and biophysical data led the committee to conclude that the risk would continue in a linear fashion at lower doses without a threshold and that the smallest dose has the potential to cause a small increase in risk to humans." [A typical person in the US receives 3 milliSieverts per year.]
That's a tepid justification for retaining LNT, but compare that with the statement from the National Institutes of Health:
"It is very difficult to detect biologic effects in animals or people who are exposed to small doses of radiation. Based on studies in animals and in people exposed to large doses of radiation such as the atomic bomb survivors, scientists have made conservative estimates of what might be the largest doses that would be reasonably safe for a person over a lifetime. But these calculations are estimates only, based on mathematical models. Low-level exposures received by the general public have shown no link to cancer induction. Even so, the U.S. Government uses these estimates to set the limits on all potential exposures to radiation for workers in jobs that expose them to ionizing radiation. International experts and various scientific committees have, over the years, examined the massive body of knowledge about radiation effects in developing and refining radiation protection standards."
And with the statement from the Health Physics Society"
"There is substantial and convincing scientific evidence for health risks following high-dose exposures. However, below 5–10 rem (which includes occupational and environmental exposures), risks of health effects are either too small to be observed or are nonexistent."
"In view of the above, the Society has concluded that estimates of risk should be limited to individuals receiving a dose of 5 rem in one year or a lifetime dose of 10 rem in addition to natural background." [5 rems would be 50 milliSieverts.]
Professor Bernard Cohen goes on to estimate what would be the health effects of low-level exposures and compares them with other health risks, using the LNT model even though he shows in his analyses that it overstates the adverse effects and probably understates the beneficial (hormesis) effects of low-level radiation.
As an exercise we'll do something simple here. The BEIR report says ten million mSv would cause 1140 deaths. And it says that, on average, 304 million Americans receive 3 mSv per year, so the total would be 912 million mSv. So all of the radiation-induced deaths add up to 104,000 per year. Of that number, according to the report, 0.2% are due to nuclear energy, the rest mainly being due to natural radiation. If the LNT hypothesis is right, 208 deaths per year can be attributed to nuclear energy.
In comparison, every study done shows that tens of thousands of Americans die every year from the pollution generated by coal-fired power plants. The most comprehensive study done so far puts the range between 33,000 and 121,000 per year, just counting adults over 25. In 2006, according to DOE, coal generated 1930 billion KWH of electricity and nuclear generated 787 billion KWH, so if nuclear replaced coal an additional 510 deaths would take place, but at least 50,000 lives would be saved.
And all of the radiation-related deaths depend on a hypothesis that hasn't been proved and which specialized professionals don't believe.
Here's the kicker: Coal plants emit more than ten times as much radioactivity as nuclear power plants. If the LNT hypothesis were true, 5000 of the coal-related deaths would be avoided by converting to nuclear energy just because of reducing radioactive emissions.
If some form of renewable energy could provide full-time power, this might be a harder decision to make. As we saw in an earlier article, though, there aren't any that could.
So those are the two options. We can let over 50,000 Americans die every year from coal or we can switch to nuclear energy and start cleaning up the environment while minimizing the threat of global warming. What to do, what to do.
Saturday, February 9, 2008
The Latest on Biofuels
This week's Science Magazine (or Science Lite as it's sometimes called) includes a story that's got a lot of press coverage (way to go, guys!) but really just fills out the picture slightly.
The authors make the point that if you increase plant cultivation for biofuels, you either have to displace existing crops or clear additional land. But if you displace existing crops then the demand for food leads to the clearing of additional land, anyway. And it's the clearing of additional land that causes the problem. This seems obvious if the clearing is done in forests, as it usually is. A mature forest contains decades' worth of accumulated carbon so if the forest is burned then most of that carbon goes into the atmosphere as CO2. It's not as obvious but, according to the authors, plowing up grassland to grow biomass also releases more CO2 than it saves.[LA Times]
It's been known for a long time that ethanol is a loser.[source] It takes as much fuel to produce it as the process yields. So, in the US at least, it's always been a boondoggle aimed at making farmers rich. Still, some researcher think switchgrass can offer a better payoff ratio.
There's been some hope that oil-bearing crops could produce biodiesel, but so far the results aren't much more promising.[source]
So that seems like a daunting challenge by itself. But then we look at the land requirements and the prospects are even more dismaying. As we showed in another article, there isn't enough arable land available to grow the amount of biomass that would be required.
Maybe all this attention will do some good. Most people whose knowledge of enviromental subjects comes mainly from popular media have the idea that biofuels are a practical solution. A closer look shows that, by themselves, biofuels can at best be only an expensive non-solution, an illusory exercise that benefits a few people financially but only aggravates the problem.
As we face this bleak outlook, there's only one thing going for us. Hydrogen can increase biofuel yields by a factor of three. Then, biofuels can function mostly as a medium for hydrogen. They provide an imperfect means for onboard storage of hydrogen fuel for motor vehicles.
The most efficient way to convert water to hydrogen is with high-temperature processes, at temperatures nuclear reactors can provide. The nominal efficiency is over 45%.[source] But the heat left over from the conversion can be used to generate electricity, so the hydrogen production is effectively 100% efficient.
If we're lucky, a better way of storing hydrogen will be invented so biofuels won't be required. Either way, hydrogen is going to be the fuel of the future. The best way to produce hydrogen is with nuclear energy.[source]
The authors make the point that if you increase plant cultivation for biofuels, you either have to displace existing crops or clear additional land. But if you displace existing crops then the demand for food leads to the clearing of additional land, anyway. And it's the clearing of additional land that causes the problem. This seems obvious if the clearing is done in forests, as it usually is. A mature forest contains decades' worth of accumulated carbon so if the forest is burned then most of that carbon goes into the atmosphere as CO2. It's not as obvious but, according to the authors, plowing up grassland to grow biomass also releases more CO2 than it saves.[LA Times]
It's been known for a long time that ethanol is a loser.[source] It takes as much fuel to produce it as the process yields. So, in the US at least, it's always been a boondoggle aimed at making farmers rich. Still, some researcher think switchgrass can offer a better payoff ratio.
There's been some hope that oil-bearing crops could produce biodiesel, but so far the results aren't much more promising.[source]
So that seems like a daunting challenge by itself. But then we look at the land requirements and the prospects are even more dismaying. As we showed in another article, there isn't enough arable land available to grow the amount of biomass that would be required.
Maybe all this attention will do some good. Most people whose knowledge of enviromental subjects comes mainly from popular media have the idea that biofuels are a practical solution. A closer look shows that, by themselves, biofuels can at best be only an expensive non-solution, an illusory exercise that benefits a few people financially but only aggravates the problem.
As we face this bleak outlook, there's only one thing going for us. Hydrogen can increase biofuel yields by a factor of three. Then, biofuels can function mostly as a medium for hydrogen. They provide an imperfect means for onboard storage of hydrogen fuel for motor vehicles.
The most efficient way to convert water to hydrogen is with high-temperature processes, at temperatures nuclear reactors can provide. The nominal efficiency is over 45%.[source] But the heat left over from the conversion can be used to generate electricity, so the hydrogen production is effectively 100% efficient.
If we're lucky, a better way of storing hydrogen will be invented so biofuels won't be required. Either way, hydrogen is going to be the fuel of the future. The best way to produce hydrogen is with nuclear energy.[source]
Friday, February 8, 2008
Bernard L. Cohen
This is the easiest to write of the articles on this blog. The only important part is a link to Prof. Bernard L. Cohen's website, THE NUCLEAR ENERGY OPTION. Here you'll find the most authoritative treatment anywhere of all aspects of nuclear energy as it relates to the public, and it's written clearly enough that any reasonably well-educated person can understand it perfectly.
This article could end right here, but maybe it's worthwhile to offer one example of his explanations. Since safety is the one place where most people's knowledge of nuclear energy is dodgy, what follows makes a good sample.
This article could end right here, but maybe it's worthwhile to offer one example of his explanations. Since safety is the one place where most people's knowledge of nuclear energy is dodgy, what follows makes a good sample.
RISKS OF NUCLEAR ENERGY IN PERSPECTIVE
With the benefit of this perspective, we now turn to the risks of nuclear energy, and evaluate them as if a large fraction of the electricity now used in the United States were generated from nuclear power. The calculations are explained in the Chapter 8 Appendix, but here we will only quote the results.
According to the Reactor Safety Study by the U.S. Nuclear Regulatory Commission (NRC) discussed in Chapter 6, the risk of reactor accidents would reduce our life expectancy by 0.012 days, or 18 minutes, whereas the antinuclear power organization Union of Concerned Scientists (UCS) estimate is 1.5 days. Since our LLE from being killed in accidents is now 400 days, this risk would be increased by 0.003% according to NRC, or by 0.3% according to UCS. This makes nuclear accidents tens of thousands of times less dangerous than moving from the Northeast to the West (where accident rates are much higher), an action taken in the last few decades by millions of Americans with no consideration given to the added risk. Yet nuclear accidents are what a great many people are worrying about.
The only other comparably large health hazard due to radiation from the nuclear industry is from radioactivity releases into the environment during routine operation (see Chapter 12). Typical estimates are that, with a full nuclear power program, this might eventually result in average annual exposures of 0.2 mrem (it is now less than one-tenth that large), which would reduce our life expectancy by another 37 minutes (see Chapter 8 Appendix). This brings the total from nuclear power to about 1 hour (with this 37 minutes added, the UCS estimate is still about 1.5 days).
If we compare these risks with some of those listed in Table 1, we see that having a full nuclear power program in this country would present the same added health risk (UCS estimates in brackets) as a regular smoker indulging in one extra cigarette every 15 years [every 3 months], or as an overweight person increasing her weight by 0.012 [0.8] ounces, or as in raising the U.S. highway speed limit from 55 miles per hour to 55.006 [55.4] miles per hour, and it is 2,000 [30] times less of a danger than switching from midsize to small cars. Note that these figures are not controversial, because I have given not only the estimates of Establishment scientists but also those of the leading nuclear power opposition group in this country, UCS.
I have been presenting these risk comparisons at every opportunity for several years, but I get the impression that they are interpreted as the opinion of a nuclear advocate. Media reports have said "Dr. Cohen claims . . ." But there is no personal opinion involved here. Deriving these comparisons is simple and straightforward mathematics which no one can question. I have published them in scientific journals, and no scientist has objected to them. I have quoted them in debates with three different UCS leaders and they have never denied them. If anyone has any reason to believe that these comparisons are not valid, they have been awfully quiet about it.
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