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User Journal

Journal SPAM: Open Apology to James Hansen 9

Dear Dr. Hansen,

This is an apology. I'm responsible, in part, for a couple of your more unfortunate public positions. My excuse is that I got tired of persistent foolishness. After laborious discussion I sent some people on to you, hoping you'd have the good sense to ignore them.

The first time I did this, I had noticed you were open minded about climate solutions. I was working with the Green Party Ecoaction Committee as the Maryland representative. Lorna Salzman, our Chair and New York representative had brought in Charles Komanoff to consult and he kept on going on and on about a carbon tax. I felt, and feel, that regulation is a smarter more certain approach, but we did mention a tax in our 2006 State of the Earth Report. I began to tire of the subject and urged, since the party was not in power, that Lorna and Charlie try to engage you in promoting their scheme. They appear to have suceeded. The trouble now is that the time to decide between regulation or a tax is past. We are going with regulation. I will say that during my work on the StepItUp campaign, Steny Hoyer made a good political argument against the tax: tax shifting could destabilize social security, a key tea party goal. My concerns had more to do with measurement and enforcement.

But, the internal arguments about how to approach greenhouse gas reduction are no longer important. We are using regulation under the authority of the Clean Air Act as ordered by the Supreme Court in Massachusetts v EPA. It is a socialist cause to have a carbon tax with dividend, but it is no longer a climate cause. Instead of sending people to you and feeling relieved that I didn't have to argue endlessly, I should have briefed you on the nature of the argument. Now, your dedication is becoming a liability as you are extending the argument after the matter has already been decided. Effective climate activism now aims at faster implementation of regulation. Briefs on the current court case in support of the Clean Power Plan, urging a steeper ramp on CAFE standards, and working to ban fracking, all regulatory issues, are what is needed.

I also sent a couple of nuclear wakos your way. There was a fellow whose father ran a failed Oak Ridge reactor experiment who wanted vindication that he felt his father deserved. His name was Charles too. He was crazy about thorium. And there was another going by the handle of "asteroid miner" who wanted breeder reactors everywhere. I let them know you might be receptive based on how you responded to the carbon tax issue. Though I think you have now seen through the thorium quackery on your own, you seem still enthralled by a pointless nuclear dream. You've proposed a huge buildup of nuclear power despite the facts that uranium will run out before the build is complete and breeder reactors often blow up and can't possibly be ready to deal with this shortage in your scenario.

Now, the other "asteriod miner" "solution" of getting uranium from seawater has run up against your new climate science. To fuel your huge new nuclear build, blocking the Gulf Stream with uranium recovery threads would be required. However, you propose that Greenland melting is already reducing that flow. You have been placed in an untenable position, in part, because I sent nuclear kooks to you.

I apologize for imposing on your time in this indirect manner. In recompense, I draw your attention to the fact that PNAS awarded its Cozzarelli Prize to a very rapid and well thought out climate mitigation plan . We don't need to rely on guesswork anymore. The peer reviewed liturature is providing a best practices approach to climate mitigation. We just need to strive for enabling regulations.

With Warm Regards,

Chris Dudley

User Journal

Journal SPAM: Material Needs for 100% Wind Water Solar Energy

I ran into a silly video comparing materials used in thermal power plants with those used in renewable energy generation. It turned out the main silliness stemmed from quoting extreme estimates from a Nature Geoscience Commentary piece by Olivier Vidal, Bruno Goffé and Nicholas Arndt of Grenoble and Aix which tried to justify a plea for more mining in Europe. The preposterousness in the video stemmed from these authors citing and outdated lifecycle analysis of solar power and then using this as an upper estimate. They did not give a lower estimate leaving the videographer space to careen off into absurdity. Such notes are typically not fully reviewed, and normally a reviewer would ask for both sides of an estimate. It turns out that asking for that produces interesting results.

We have the advantage of time in taking on this question because recent work on energy demand supercedes that used by the authors. They presume energy demand will grow with development as it would in the absence of a transition to renewable energy, but, mostly because transitioning to renewable energy is accompanied by electrification of all sectors, energy efficiency stops demand growth for energy. Mostly, more people driving cars means less energy use as the cars are electrified. However, this electrification also squeezes out biofuels which were a dominant source in the scenario the authors considered for 100% renewable energy, so it turns out we may expect 3 time more energy to come from wind and solar power than they assumed in their fig. 1.

Usually, these materials based criticisms of renewable energy are focused on things that could be in short supply. Often tellurium is cited because it is used in one kind of solar cell. Tellurium is common on the seafloor but the real problem with such an approach is that the most common type of solar cell is made from sand, which is very easy to find almost anywhere. Basically there are substitutes for any "bottleneck" material for renewable energy unlike fuel which constrains all non-renewable energy other than deuterium fusion. The authors recognize this and so concentrate on common materials: copper, aluminum, steel, concrete and glass.
The authors' main point is that production of these material will need to increase to transition to clean fuel-free energy and they explore constraints related to this. Now, while we make the energy requirement for wind and solar larger, we do so in the context of realizing that learning curves are quite strong in these technologies. That is why they offer a least-cost path forward. So while the authors consider lifecycle analysis for 3 MW wind turbines, we should acknowledge that most of the wind power will use at least 15 MW turbines (8 MW already being built ) so material requirements will be reduced. (Our guideline scenario conservatively uses 5 MW). Further, solar panels are becoming more efficient and we may expect the majority to have material demands much less than any considered by the authors. On balance, the higher contributions of wind and solar considered here are likely offset by reasonable reductions in material requirements leaving the authors' estimates for the filled symbols in their fig. 1 approximately correct.

But, now we come to a new issue. When we transition to renewable energy, particularly when avoiding combustion technologies, a great deal of material that we use now is no longer needed. Coal cars and indeed whole rail lines use steel that can be recycled. Oil and gas pipelines may be ripped up and tanker cars, trucks and ships may also surrender their metal constituents. The aluminum engine blocks of cars will also be unneeded. And, with greater reliance on electricity, more high temperature superconductors will replace copper cables in cities. Similarly, electric cars may be made with more composite materials rather than steel since they are intended to be more durable to match their superior drivetrain.

Let's make some estimates. There are about one billion cars on the road now and we can be sure that 70% at least will have aluminum engine blocks by the time we switch to electric vehicles since fuel efficiency standards are rising. If we estimate 44 lbs per block, that comes to 14 million tonnes. Aluminum coal hoppers probably yield back a similar amount at 20 tonne per car. So, we've freed up a year or few of production. Perhaps solar panel frames will be made from composites, which appear to be superior to aluminum in any case.

There are about 130 tonnes of steel per mile of rail and about 160 thousand miles in North America. Taking a factor of 4 more for the world and 10% used for coal alone, we'd recover 5 million tonnes of steel. There are also about a billion tonnes of oil tankers. Assuming oil and gas pipelines use 50 times more steel per mile than rail, they yield back 20 billion tonnes. Together, this seems to provide for a steel glut even after a renewable energy transition. Note that we do not consider steel from redundant nuclear reactors since they convert useful steel to nuclear waste. A shift to composites for autobodies would compound the steel glut by a smaller amount than oil and gas infrastructure recycling.

Concrete and glass do not seem to be big issues in terms of constraints and it may be that graphene will replace glass in any case.

Contrary to the authors' contention that the materials they consider have no substitutes, they often substitute for one another, aluminum for copper in conduction, steel for concrete in construction, and we are seeing the introduction of new materials such as high temperature superconductors and composite materials to replace many of these. Composites are an enabling technology for larger wind turbines and so play an inevitable role there.

We may conclude that the authors' concerns are too weighty for the actual situation and in the case of steel we may anticipate glut rather than scarcity.

User Journal

Journal Journal: Explanatory Note for "Better Home Through Chemistry"

Songs, like jokes, probably suffer fatalities from explanation. However, the song "Better Home Through Chemistry" has some references to the chemistry literature and some abbreviations of synthesis steps, so it will be explained regardless.

The aim of the song is to return much of the Great Plains of North America to wilderness, restoring buffalo habitat. This is accomplished by eliminating most agriculture in support of animal husbandry by synthesizing sugar directly from the atmosphere using renewable energy inputs. Each American has about 500 lbs of animals eating on our behalf to supply milk, meat and eggs, so most of our grain production is used to feed those animals. If they can be fed using synthetic feed, much less agricultural land would be needed and wild habitat can be restored.

While the synthesis chain described in the song is probably not optimal, it demonstrates a path to glucose synthesis. The main insight, however, is that plants are not nearly as efficient at harvesting solar energy (for our subsequent use) as we are when we use solar panels. For corn, we get about a quarter watt per square meter compared to about 40 with a solar panel.

The challenge, then, is to convert that electrical energy into chemical energy in a digestible form. If we do so, then land area that is desert may be substituted for cropland at a very favorable ratio and cropland can be released to a carbon negative native grassland, and a habitat for buffalo.

It has been noted that obtaining carbon dioxide directly from the atmosphere is not all that costly energetically, so we'll assume that. We then split water into hydrogen and oxygen and use the Sabatier reaction to produce methane as mentioned in the song. This is exothermic and can supply process heat as needed for further steps. So, we have now converted electrical energy into chemical energy.

The song skips the steps of converting methane to acetylene, acetylene to acetaldehyde, and acetaldehyde to acetic acid, all standard industrial processes. It then describes converting acetic acid (vinegar) into ethanol (wine) using the Zhang et al. process.

Ethanol is then converted to propylyne using another recent process described by Iwamoto et al.

Those steps are mentioned in the song which then skips propylyne to epichlorohydrin and handwaves epichlorohydrin to d-glyceraldhyde which passes through glycerol. This provides the input for Kiliani-Fischer synthesis which produces a range of sugars, including d-glucose, our target. Those which are not edible can be reprocessed for another try since they represent substantial chemical energy, or they may be good for use in fuel cells.

Addendum: The Gulf of Mexico suffers from a dead zone brought on by too much nitrogen and phosphorous draining from cropland into the Mississippi River. Restoring buffalo habitat would eliminate this problem.

It may be objected that ruminants need fiber as well as sugar. That problem seems to be solved .

Making this a national priority would also honor the buffalo as our new National mammal. (Slashdot )

This also allows survival of nuclear winter/super volcano/asteriod impact induced dimming in style .

Doing exactly what plants do but better is discussed here, but it has been suggested that deriving foods from fossil fuels could reduce cancer risk owing to reduced carbon-14 burden. Instead of getting carbon dioxide straight from the air as suggested here, we might initially get it from fossil fuel power plants, and later from cement factories and make our milk, meat and eggs safer to eat. This would make the project for using greenhouses for crops suggested in the link five times easier since they would only need be grown for human consumption. Note that the oxygen stream produced when splitting water would make carbon dioxide capture very easy if used in combustion.
User Journal

Journal Journal: Remembering Flight MH370 1

Flight MH370 gave up a small shred of itself on the East Coast of Africa recently, but after two years, that is only the second bit of wreckage to be found. The strangeness of the lose inspired me to write this song not long after the crash. It honors air disasters going back to the first. The title is Daedalus . This is also the first time I've played bass. Expect to improve hereafter.

User Journal

Journal Journal: A use for market simulations 4

Free market economists are very very protective of their theory for good reason. They demonstrated that the free market is more efficient than a planned economy and won the cold war, defeating communism.

But let's be clear, a free market is not free, it is regulated. Certain transactions are prohibited. For example, if you are asked to pay for the privilege of me not pulling the trigger of the gun I have aimed at you, that is not allowed, even if you could instead choose to pay somebody else 10% less and there were market competition in armed robbery.

A regulatory structure that preserves certain conventions, in this case property rights, is needed for market theory to work.

Armed robbers are sent to jail even if they didn't pull the trigger, but polluters continue to pollute even when they actually kill a lot of people. They are just exercising their property rights, which need to be protected.

It is possible to add regulations on pollution similar to regulations on armed robbery, and considering the huge loss of life from pollution compared to armed robbery, long jail sentences for all polluters would be proportional. But, instead, free market economists want to impose a pollution fee or an emissions trading system and double down on markets, claiming it is an efficient method to cut pollution.

But I think things have changed since the cold war. I think numerical simulations of markets are available now that can capture the main efficiencies that such approaches might produce and provide a recipe for ending pollution that can be carried out directly, without going through the exercise of administering a fee or trading scheme. At some point the failure of simulation to capture the last dregs of market efficiencies is insignificant compared to the administrative and moral costs of playing market with people's health and lives.

So, let the market theorists use their theory to find which pollution sources should be closed in which order, and we'll make that the list we use without a fee or a trade system. And, I think those same economists can show that doing it this way will be better since it will allow us to deploy job retraining programs and avoid defaults on pensions in the polluting industry that would otherwise become large socialized costs in an actual market scheme.

User Journal

Journal Journal: Employment

President Obama wants to add wage insurance to unemployment insurance so that taking a lower paying job doesn't blow your mortgage. This sounds like a reasonable response to lower job security, though adding it to the earned income tax credit might be a better move. A place where the President has done well is in trying to place veterans in jobs. And recent work shows veterans children are, still suffering from their fathers' service. Government policy can have very direct consequences for workers.

One place we may anticipate this is in energy policy, where we will be shifting more and more away from coal mining. Now there a currently more jobs in renewable energy than in coal so over all, the policy boosts employment. But, it can't do that right where coal miners live. Tennessee has attracted silicon refining which helps and employment is high there. But a pound of silicon is worth 200 pounds of coal, so, with time, the material volume can't keep up with the effort involved with coal extraction. The potential of the world market notwithstanding, renewable energy will have less employment in the end than fossil fuels. It will enable more employment in other sectors by making energy cheaper, but energy sector employment must ultimately shrink as getting energy becomes a very passive pursuit.

So, it is encouraging the the President linked rebuilding our transportation system to helping out coal miners, because that is a job that is big enough to cover their numbers. And, instead of wage insurance, I'd urge signing bonuses. GM owes the President. The BOLT should be built in coal country at wages higher than for mining. And, there should be a signing bonus for every experienced miner who quits to work on the BOLT. It should be a rapid transition that makes it very hard for mines to retain employees.

A raise and a bonus should be the reward for leaving the mine.
User Journal

Journal Journal: PAX SOLARIS

Solar is the most conservative power source ever and, once adopted, will never be displaced. It is really the nature of conservatives that makes it this way. Conservatives used to hate coal because unions got such strength from organizing mines. But now they love coal because the unions are busted owing to mechanization. Coal has a flag wrapped around it.

But, conservatives also like to believe in free markets. And solar power is becoming cheaper than coal. And, once deployed, it involves very little labor. So solar power ends up looking more like an investment than a seed for revolution.

This is really key. Once deployed, solar power becomes the glorious patrimony which all good conservatives are honor bound to defend just like family values.

Conservatives have supported wind power to some degree and nuclear power is glorious patrimony these days so it gets reflexive support as well as anti-antinuke support. But the only real competitor for the affections of conservatives for solar is natural gas. And, conservative supporters of natural gas are wrecking its advantages by attempting to export it.

There isn't a free market in natural gas or oil outside the US so natural gas exports mean higher prices domestically. Solar power will thus beat the price of natural gas all the sooner because it can hold on to the efficiency advantages it accrues through investment in technology while natural gas will not owing to foreign market manipulation.

Many of the things that make conservatism objectionable will also evaporate when solar power is fully deployed. The military hegemony in the Mid-East will be much less fraught, and the superabundance of energy will make conservative objections to population policy less grating. Conservatism will grow. PAX SOLARIS will likely be longer lasting and more conservative than PAX ROMANA. And that is about as conservative as it gets.

User Journal

Journal Journal: Taxoholics 3

During the StepItUp campaign to get Congress to set a policy for the United States to cut carbon dioxide emissions 80% by 2050, I had a chance to talk with Steny Hoyer about what practical steps might help. One thing we discussed was using a tax on carbon to bring down demand and improve the economic environment for substitute ways of producing energy. He'd been thinking about it and had noticed how large a tax would be required and how some were suggesting a shift in taxation for social security. His point that this would be destabilizing for social security since it would take it out of its insurance model of funding was thoughtful.

Since then, the Supreme Court compelled the EPA to consider the dangers posed by greenhouse gas (GHG) emissions, and, the danger having been recognized, regulations have been promulgated to reduce emissions. Thanks @BarackObama

It turns out, Congress already acted when it passed the Clean Air Act. So why do we still hear about a carbon tax, when regulations are doing the job?

Some think that markets have a magical efficiency that regulations can never match. This point of view is mistaken because it confuses market efficiency in distributing goods with effective policy.

But mostly it seems to be willing blindness. As an example, Charles Komanoff claims that Corporate Average Fuel Economy (CAFE) standards increase owing to increased fuel prices. Basically he is urging that Congress make a carbon tax to get Congress to increase CAFE standards. A very circular and confused mode of thinking, but also wrong in the premise. CAFE standards were first implemented to reduce our dependence on foreign oil and have been increased because the EPA determined that GHG emissions are dangerous. Those are national policy issues not some worry about prices.

We can see further confused thinking when he discusses price elasticity. It is very well known that price does not affect gasoline consumption much. People still have to get to work. Over the long run, high gasoline prices do slow the economy creating unemployment and people don't go to work, but that is macroeconomics, not elasticity. Komanoff dances around this but tellingly claims that elasticity is better for industrial consumers with more options for substitution while simultaneously claiming that the carbon tax is not laid squarely on the backs of people who need to get to work. More confused thinking.

Komanoff also misunderstands the problem. He wants to slowly phase in his carbon tax, but action is needed urgently for GHG emissions. He also wants to reduce but not eliminate emissions, but that ship has sailed from a dock on the River Seine, and mathematically, a tax just can not bring emissions to zero, only regulations can do that.

A carbon tax, regardless of its other impracticalities, is just too little too late and a pointless distraction promoted by confused thinking only.
User Journal

Journal Journal: Academic Honor Code 2

I went to schools with academic honor codes. I remember deep qualms when it came time to assent to these codes. I agreed that cheating was dishonorable, but I also worried that reporting others for cheating was dishonorable, and that was a part of the codes. My daughter recently reported a social media cyber bullying situation and had it taken down. Someone got suspended too. She is less of a fence sitter than I was.

I notice now a severe case of academic cheating. Major fossil fuel companies knew about global warming from their own academic research and then lied about it.

Schools with honor codes need to address this if they are holding investments in these companies. As a matter of honor, they must divest. Harvard started an honor code last fall. President Drew Faust can not retain academic integrity and still oppose divestment.

Of schools with honor codes only Stanford has committed to divestment, and so far, only from coal, though the biggest academic cheaters seem to be oil companies.

It will be worth watching to see if the schools with honor codes will live up to them and divest from companies that promote academic dishonesty.
User Journal

Journal Journal: 61 reactors a year 4

Not long ago, four climate scientists wrote about nuclear power . It is not hard to look up how much uranium can still be mined at a reasonable cost. In terms of how quickly we use it now, there is about 80 years left.

The climate scientists pointed out that fossil fuel electricity generation could be replaced if 61 reactors a year were built for 35 years. So, 61 reactor per year. 35 years: 2135 reactors. 5.3 times number of current reactors. On average over 35 years, the rate of uranium consumption goes to 1+5.3/2 current rate, about 3.65 times faster. Available uranium will last 80 years with no change so 22 years at the new rate. So, we'd run out of uranium before finishing the build.

It is fine to propose this kind of scenario for renewable energy, but for technology that requires fuel, you need to check that there is some fuel. That is, after all, why we pursue fusion energy. We realized in the 1970s that both coal and uranium would run out. Duterium is abundant enough that it doesn't have that problem.
User Journal

Journal Journal: 61 reactors a year

Not long ago, four climate scientists wrote about nuclear power . It is not hard to look up how much uranium can still be mined at a reasonable cost. In terms of how quickly we use it now, there is about 80 years left.

The climate scientists pointed out that fossil fuel electricity generation could be replaced if 61 reactors a year were built for 35 years. So, 61 reactor per year. 35 years: 2135 reactors. 5.3 times number of current reactors. On average over 35 years, the rate of uranium consumption goes to 1+5.3/2 current rate, about 3.65 times faster. Available uranium will last 80 years with no change so 22 years at the new rate. So, we'd run out of uranium before finishing the build.

It is fine to propose this kind of scenario for renewable energy, but for technology that requires fuel, you need to check that there is some fuel. That is, after all, why we pursue fusion energy. We realized in the 1970s that both coal and uranium would run out. Duterium is abundant enough that it doesn't have that problem.
User Journal

Journal Journal: Shutting down the right to petition

The Bill of Rights includes a right to petition the government for redress of grievances. When the government has erred, the people must demand redress. But what happens when the government makes a mistake, and then shuts down the petition process?

That is exactly what is happening now at the Nuclear Regulatory Commission (NRC).

"Last year, a federal appeals court sided with the states of New York, Connecticut, Massachusetts and Vermont, which argued the Nuclear Regulatory Commission wrongly assumed spent reactor fuel eventually would move to a permanent waste repository, even though the Obama administration canceled the Yucca Mountain project in Nevada."

Previously, the courts had ruled that Yucca Mountain would not work, and data fabrication by government scientists had put into question the ability of the Department of Energy to even manage such a project.

As a result, the NRC is not allowed to issue licenses for nuclear power plants until it clears up this mistake, though is seem happy to give up on proper procedure and allow nuclear power plants to operate without a license.

So, now the people are supposed to have their say, exercising their right to petition their government through the public comment period. But the NRC is closing up its ears, cancelling public meetings and shutting down our constitutional right.

While it may be a fair point brought up by "Janet Phelan Kotra, who worked for the commission for more than 28 years and served as project manager for the waste confidence issue for 14 years, [when she] said the proposed new rule is improperly based on the idea that the commission has confidence in the safety of long-term storage at reactor sites rather than on confidence that a permanent repository will become available in a reasonable time frame." Telling everyone else to just shut up seems like a violation of a very primary right.
User Journal

Journal Journal: Is Indian Point Next to Close? 1

Nuclear power plants are retiring early all over the country and planned power uprates are being canceled. With the recent decision to close Vermont Yankee, it comes to five closed reactors and five canceled uprates.

Now Entergy, the troubled owner of Indian Point close to New York City, is issuing denials that it will close Indian Point just as it had until so recently issued denials that it would close Vermont Yankee.

A second law suit has been filed against Energy by security employees saying the Indian Point plant is vulnerable to attack. And with the checkered history of violations by Entergy on this score, it seems likely that the coverups described in the suit have been occurring as per usual. Vermont Yankee was on the list of the ten most likely to retire early constructed by analyst Mark Cooper (linked above).

  • Palisades (Repair impending, local opposition)
  • Ft. Calhoun (Outage, poor performance)
  • Nine Mile Point (Site size saves it, existing contract))
  • Fitzpatrick (High cost but offset by high market clearing price)
  • Ginna (Single unit with negative margin, existing contract)
  • Oyster Creek (Already set to retire early)
  • Vt. Yankee (Tax and local opposition)
  • Millstone (Tax reasons)
  • Clinton (Selling into tough market)
  • Indian Point (License extension, local opposition)

So is Indian Point. I'd guess that chances are better than nine to one that it will be next.
 

Earth

Journal Journal: Fossil Fuel Use Cuts Body's Internal Radiation Burden

Many discussions of nuclear power on slashdot are polluted by references to completely bogus calculations at the Oak Ridge National Laboratory web site that claim that coal power plants emit more radiation into the environment than nuclear power plants. This is completely bogus because when coal is burned, the uranium within it remains in the ash and its concentration is no greater than in typical low carbon soils. You might as well say that a bulldozer pushing clay soil around is releasing radiation into the environment. Why? Because the uranium in coal comes from the soil out of which the primaeval forest grew. When the coal is burned, you just get the soil components back. It always seemed curious that a national laboratory, even one so captured by the nuclear industry, would be yanking everyone's chain like that, making such preposterous claims. It could just be stupidity. But....

One thing about fossil fuels is that they have been isolated from the atmosphere for a very long time. That means that the carbon-14 produced by cosmic ray impacts with nitrogen nuclei in the atmosphere that they originally contained has pretty much decayed away. So, when fossil fuels are burned, carbon-14 in the atmosphere is diluted with respect to carbon-12 in the atmosphere. But that diluted mix is just where our food comes from, and since we are what we eat, we end up with less carbon-14 in our bodies. If we were to instantaneously double the concentration of carbon dioxide in the atmosphere by burning fossil fuels, the amount of carbon-14 in our bodies would go down by half. This would cut the beta decay rate from carbon-14 in our bodies by half and the combined beta decay rate from potasium-40 and carbon-14 by about 12%. If we subsequently removed carbon dioxide from the atmosphere to control the climate, carbon-14 would be removed together with carbon-12 and the internal radiation burden in our bodies would remain low for thousands of years as carbon-14 production would catch up on a timescale similar to the decay timescale for carbon-14 (5700 years).

Now, potasium-40 decays are more energetic than carbon-14 decays but carbon-14 in incorporated in DNA and thus decays may have a greater chance of inducing mutations, the apparent origin of cancers.

Nuclear power use, on the other hand, only increases radiation exposure, it does not decrease it. And it does so for long long after there has been any benefit from the power generation. While there are immediate cancer risks in the chemical components emitted from coal, gasoline or diesel burning, those risks are incurred by those benefiting from the fuel use and are not transmitted down the ages. The long term cancer legacy, in fact, is reduced cancer risk owing to reduced internal radiation burden.

A review of carbon-14's especially damaging roll in DNA may be found here .
Earth

Journal Journal: Fossil fuel use cuts body's internal radiation burden 3

Many discussions of nuclear power on slashdot are polluted by references to completely bogus calculations at the Oak Ridge National Laboratory web site that claim that coal power plants emit more radiation into the environment than nuclear power plants. This is completely bogus because when coal is burned, the uranium within it remains in the ash and its concentration is no greater than in typical low carbon soils. You might as well say that a bulldozer pushing clay soil around is releasing radiation into the environment. Why? Because the uranium in coal comes from the soil out of which the primaeval forest grew. When the coal is burned, you just get the soil components back. It always seemed curious that a national laboratory, even one so captured by the nuclear industry, would be yanking everyone's chain like that, making such preposterous claims. It could just be stupidity. But....

One thing about fossil fuels is that they have been isolated from the atmosphere for a very long time. That means that the carbon-14 produced by cosmic ray impacts with nitrogen nuclei in the atmosphere that they originally contained has pretty much decayed away. So, when fossil fuels are burned, carbon-14 in the atmosphere is diluted with respect to carbon-12 in the atmosphere. But that diluted mix is just where our food comes from, and since we are what we eat, we end up with less carbon-14 in our bodies. If we were to instantaneously double the concentration of carbon dioxide in the atmosphere by burning fossil fuels, the amount of carbon-14 in our bodies would go down by half. This would cut the beta decay rate from carbon-14 in our bodies by half and the combined beta decay rate from potasium-40 and carbon-14 by about 12%. If we subsequently removed carbon dioxide from the atmosphere to control the climate, carbon-14 would be removed together with carbon-12 and the internal radiation burden in our bodies would remain low for thousands of years as carbon-14 production would catch up on a timescale similar to the decay timescale for carbon-14 (5700 years).

Now, potasium-40 decays are more energetic than carbon-14 decays but carbon-14 in incorporated in DNA and thus decays may have a greater chance of inducing mutations, the apparent origin of cancers.

Nuclear power use, on the other hand, only increases radiation exposure, it does not decrease it. And it does so for long long after there has been any benefit from the power generation. While there are be immediate cancer risks in the chemical components emitted from coal, gasoline or diesel burning, those risks are incurred by those benefiting from the fuel use and are not transmitted down the ages. The long term cancer legacy, in fact, is reduced cancer risk owing to reduced internal radiation burden.

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