Friday, April 26, 2013

Nuclear Power and Carbon Emissions:

Doing the Numbers

A recent article caught my attention because it was titled "Nuclear is NOT a Low-Carbon Source of Energy."  Now, this puzzled me.  In the first place, this is not a new argument, and in the second place, I thought it had been addressed a long time ago.
I remember that, some years ago, the claim emerged that nuclear power only looked clean because the last step was clean--if you took the other steps into account, the argument said--especially the enrichment--nuclear power wasn't so clean at all.  (Actually, the argument was originally made in terms of net energy produced as opposed to carbon emissions, but the point is the same.)  At the time, I did a back-of-the-envelope calculation on the enrichment step that convinced me that the energy used per unit of energy produced was reasonably small, even with the gaseous diffusion enrichment process, and subsequent research convinced me this calculation was right. 

So why, I wondered, was I reading the same thing all over again, this time focusing on carbon emissions.  When I reviewed the recent article, I saw right away that it was really all over the place in its opposition to nuclear power.  It dredges up every anti-nuclear argument, and even starts with the fact that scientists are not always right!  There is far more in this article than I want to tackle in a single post, but what stood out for me is that some of the points made are qualitatively valid (that is, they have identified emissions that do exist), but there is no quantification--and even more important, there is no comparison with other energy sources.

Furthermore, the article quotes sources that claim that, "The energy put into mining, processing, and shipping uranium, plant construction, operation, and decommissioning is roughly equal to the energy a nuclear plant can produce in its lifetime. In other words, nuclear energy does not add any net energy."  Now, this statement is bizarre on the face of it.  Even among people who believe that government and industry are the Evil Empire, most must find it a stretch to believe that so many people could have successfully pursued a strategy that didn't add net energy for such a long time.

Tracing back some of the arguments in the recent article led me to reports done around 2006 that detail some of the sources of carbon emissions from the nuclear fuel cycle (which in turn draw from a 2005 report by Storm and Smith).  Again, the arguments presented are qualitatively correct.  Mining, transportation, enrichment, construction, etc., for the nuclear fuel cycle are all energy intensive processes.  

BUT, most (although not all) of these same steps exist for other energy sources as well.  You can't capture the energy from wind or the sun efficiently and at large scales without using exotic materials such as rare earths, which have to be mined and transported.  (And some of which, by the way, may be in short supply, or may make us dependent on other countries, or may yield some quantities of hazardous waste.)  Perhaps the quantities required are smaller than the amount of uranium that must be mined, but all energy sources require materials and the mining and processing of all materials required for each technology must be taken into account if different energy sources are to be compared fairly.

Enrichment, of course, is unique to nuclear power, and is energy intensive but as noted above, is not so energy intensive as sometimes claimed.  And gas centrifuges, which are far more efficient than diffusion, are supplanting the diffusion process. 

What really took me by surprise, however, was to see the article mention the steel and concrete needed for nuclear power plants (which, of course, are made using fossil fuels).  The reason I was surprised is that recent reports have noted the much larger requirement for construction materials for the many windmills that would be needed to replace one fossil or nuclear power plant.  So raising this issue only draws attention to an measure that doesn't seem favorable for wind. 

The real point is that any such numbers must be compared to the numbers from other energy sources.  There are, in fact, a number of organizations that have done just that, and their results show that 1) nuclear power does indeed produce net energy, and a lot of it, even when the whole fuel cycle is considered, and 2) the energy use/carbon emissions of the nuclear fuel cycle is less than that of most other forms of energy when a fair comparison is made.

Some reliable sources of such studies include a study done by Yale University of life cycle greenhouse gas emissions of nuclear electricity generation, and a review conducted by the Intergovernmental Panel on Climate Change (IPCC).  Although I regard these sources are reliable, I can't claim to have reviewed every one in detail and verified all the data and calculations.  I must leave that to others.  A Wikipedia page on life-cycle greenhouse-gas emissions of energy sources provides references to other studies.  Finally, while some might consider the World Nuclear Association a biased source, their energy analysis of power systems includes a useful discussion of areas for which comparisons are straightforward and other areas for which comparisons may be more difficult.

Another concern I have is that many studies of net energy production assume that the future is rather static.  It is, of course, one thing to give credit for technology advances that have not yet been achieved, but it is another thing to fail to give credit for substitutions by technologies that already exist.  For example, an enrichment facility clearly could draw power from a nuclear plant, so the carbon emissions associated with enrichment are not a law of nature.  Rather, they are a consequence of the way things are done now.   

When looking farther ahead, we must recognize that advances are possible in all areas--but they are not to be counted on.  We all know that a major shortcoming of solar and wind systems is their intermittency.  Solutions are often proposed that involve either advanced storage technologies and/or advanced grids (and backup power sources of some variety).  While there are promising developments in both areas, they are not yet reality, and furthermore, the costs and the environmental footprint of any of these options must be incorporated into future studies.

Another example involves the possibility of using small, modular reactors (SMRs) to supply needed power for mines.  This could, of course, substantially reduce emissions associated with mining operations for a variety of energy sources.  This scenario has actually been considered by mining operators, such as for mining oil sands in Canada, so it would seem that this is not a far-off vision.  Nevertheless, SMRs are not yet a fully developed technology, and must be treated as speculative in any projections of carbon emissions from different fuel cycles.

Likewise, as already noted in some of the more negative assessments of nuclear power, the implications of using lower-quality uranium ores, should that be necessary, must be considered.  At present, it appears the supplies of uranium are adequate, and further exploration plus the potential for using a thorium fuel cycle could push the need to tap lower-quality ores far into the future.  However, whenever we speculate about such possibilities as achieving a limitless resource by extracting uranium from seawater, we must both assess the state of the technology to do that, plus add the higher energy use necessary to extract uranium from such sources.  While we may anticipate advanced technologies that would be more efficient, we should recognize that they are still in developmental stages.  


Saturday, April 20, 2013

Renewable Energy and Reality:

Growing Recognition of the Limits and Drawbacks

Although this is supposed to be a blog about nuclear energy, I keep finding myself drawn to discussing the world in which nuclear energy operates, including the pros and cons of alternative energy sources.  As readers of this blog know, I have long been concerned that most of the public seems to believe that there are easy solutions to our energy problems.  That the intermittency problems of "new" technologies such as renewables can be solved quickly, reliably and economically.  That these technologies are more "natural" and cleaner and greener. 

In other words, the "paper reactors" of Admiral Rickover's day have been replaced in people's minds by "paper solar power plants" and "paper wind farms."

I was therefore very pleased to find a couple of articles that raise some specific points that reinforce the arguments I have been trying to make.  While I may not agree with the authors in every respect, I do agree with some major points they make.  Since most of the press seems to focus on the issues associated with fossil and nuclear power, I hope that highlighting articles such as these will help balance the dialogue.   

The first article I want to discuss is an interview with Ozzie Zehner, the author of a new book called  "Green Illusions: The Dirty Secrets of Clean Energy and the Future of Environmentalism."  The article starts by pointing out what I said above--that many people believe that the answer to climate change (as well as to other downsides of current fossil fuel energy sources) is to shift from fossil fuels to "clean, green, renewable, alternative energy." The problem with such a solution, the article goes on to say, is that things are never as simple as they seem, and that "there's actually no such thing as a free lunch" when it comes to energy consumption and production. Further, what we're often told is "green" and "clean" is actually neither.

While I haven't had a chance to read the book yet, Zehner's description is clearly very much along the lines of my own thinking.  He says that this book  "...isn't a book for alternative energy. Neither is it a book against it. In fact, we won’t be talking in simplistic terms of for or against, left and right, good and evil ... Ultimately, this is a book of shades." 

In answer to a question about whether we can move from fossil fuels to solar and wind energy, Zehner says:

There is an impression that we have a choice between fossil fuels and clean energy technologies such as solar cells and wind turbines. That choice is an illusion. Alternative energy technologies rely on fossil fuels through every stage of their life. Alternative energy technologies rely on fossil fuels for mining operations, fabrication plants, installation, ongoing maintenance and decommissioning. Also, due to the irregular output of wind and solar, these technologies require fossil fuel plants to be running alongside them at all times.

Zehner goes on to say that every energy generation method has side effects and limitations.  He mentions several, but I will highlight one:

Finally, we have to consider the mining, health, pollution and waste problems of renewable technologies. For example, we are now learning that the solar cell industry is one of the fastest growing emitters of virulent greenhouse gases such as sulfur hexafluoride, which has a global warming potential 23,000 times higher than CO2, according to the Intergovernmental Panel on Climate Change (IPCC). 

This, coupled with the fact that solar power usually relies on fossil fuel backup, makes it unlikely that converting to solar power will really solve climate change. 

I can't subscribe to everything that Zehner says.  In particular, he sees the only solution as being to "bring the population down over time as we also reduce per-capita consumption."  While I can see improvements in energy efficiency, even possibly substantial ones, it is harder to see how we will achieve enough through efficiency alone, and achieving the kinds of reductions in population that he seems to think are necessary is far easier said than done.  I am more optimistic that a spectrum of advanced energy technologies (including improvements in efficiency) can meet the world's energy needs.

Although that is an important point to Zehner, I think we can disagree on that but still agree that every generation method has both pros and cons.  Zehner has provided a service by bringing greater attention to the challenges we will have to face as the use of renewable technologies grows.

The articles on Zehner's book brought my attention to a two-year-old op ed by Paul Krugman on "renewable energy's not-so-bright side."  Krugman takes issue with some reports that came out two years ago that claimed that "we can have a fully renewable-based, nuclear-free economy by 2050."  And, "What’s more, the world wouldn’t have to pay that much more for energy than it does today."

Krugman points to his personal experience, early in his career, where cost projections for energy proved wildly wrong.  "They were much too optimistic about the costs of alternative energy sources, especially alternatives to oil. Basically, the engineers were understating the difficulties involved. Later, economist Marty Weitzman would formulate a law: the cost of alternatives to crude oil is 40 percent above the current price — whatever the current price is."

Krugman implicitly acknowledges that this formula may also be too simplistic, saying that, "To be fair, we probably have much more solid ideas about the costs of wind and solar power than we did about shale oil and coal liquefaction back in 1973: wind is already a widely used technology, and concentrated solar power is pretty well understood, too."

Nevertheless, he concludes, "But there will be surprises, not all of them positive."

This is a caution we all need to keep in mind, whether we are making projections about renewable technologies, advanced nuclear technologies, or new carbon-capture technologies for coal plants. 


Saturday, April 13, 2013

Speaking on Nuclear Power:

 How Others See Us

Although I try hard not to focus on what other people think of me, every once in a while, I learn something about myself--or about what others think of me--that interests me.  This week, I came across two contrasting perspectives.  Since they relate to what I'm trying to do in this blog, I thought it might be worth looking at how people view things I have said and done.

The most recent piece was by fellow nuclear blogger Rod Adams who writes at Atomic Insights.  In his April 9, 2013 blog, he reacts to my last blog speculating whether natural gas is going to turn out to be a "flash in the pan."  Rod says the following about me:

I know Gail on a personal level and believe that she is wonderfully incapable of seeing purposefully destructive marketing behavior. Like many technically-trained nuclear professionals, she projects her natural integrity onto others who do not deserve it.  

Rod goes on to reproduce a comment he left on my blog indicating that "one of the factors behind the natural gas bubble is a purposeful effort to derail the nuclear revival."

While I appreciate Rod's compliment to my integrity, and I hope I do live up to a high standard of integrity, I really don't think integrity has anything to do with the views I expressed in my blog.  I find it more productive to focus on the facts, and not the motives, so whether the gas bubble is engineered or whether it is a case of market forces is generally not too important to me.

In fact, I was pointing out in that blog that two different articles predicted that the gas bubble was likely to be temporary and that we should not be putting all our eggs in one basket.  Both articles, to varying degrees, talked about nuclear power as one option to achieve diversity.  A third article took a more limited focus, and perhaps that is where I got myself in trouble.  That article suggested that power purchase agreements (PPAs) for wind farms could exert a downward pressure on rising gas prices.  While the article focused on wind farms, I noted that PPAs are, or can be, used for other sources of energy as well.  I didn't say so, but they can be used for nuclear power.

Unfortunately, I ended the article by saying that perhaps PPAs would allow us to "buy time" as the full dimensions of the gas bubble become clear.  I did not mean that we should do nothing and I apologize if this was not clear.  What I had in mind was that new build of any type takes time.  This article was describing a mechanism that was already in place for many wind farms.  Extending this concept might defer or dampen the gas bubble.  I admitted I was unable to predict what impact they would have in the long term, but felt that they might help us in the shorter term.

By contrast, this same week, I discovered a five-year-old blog on "nuclear lobbyists"--and was surprised to find that my name was prominently listed.  I really don't know much about this blog and had never seen it before, but it appears that they were trying to impugn the integrity of anyone and everyone who had expressed the view that nuclear power provided clean and safe energy.  Their narrative and their list of so-called "lobbyists" included people like former NRC Chairman Dick Meserve, former OECD Secretary General Don Johnson, and many others.

The main evidence against me:  "The woman appointed as deputy director of Bush's DOE, Gail H Marcus, was also president of the American Nuclear Society. The political fix was in from day one."  I found that particularly interesting.  I came to DOE in December 1999.  The US President at the time was Bill Clinton.  George Bush wasn't elected until almost a year later and didn't take office until January 2001.  And I didn't even run for president of ANS until the spring of 2000, and didn't begin my term as president until June 2001, well after I came to DOE.  Furthermore, the ANS adheres very carefully to the rules that prohibit non-profit professional societies from lobbying.  

They also reported that Dick Meserve and I spoke at a conference on the nuclear renaissance in 2002.  At that time, he was Chairman of the NRC and I worked in the DOE Office of Nuclear Energy.  In those post-9/11 days, Dick Meserve spoke on the existing resistance of US plants to a physical attack and the reexamination underway.  I spoke about DOE's programs and plans to support new nuclear power plants.  I didn't think that made either of us lobbyists.

As I read through this piece, I caught many other errors, and I'm sure there are some that I missed.  I won't try to list them all.

The point of this discussion is not to try to correct or change the perceptions of others about me.  Nor is it to suggest that my approach is better than the approach of others.  I expect to continue to write and speak about the role of nuclear power and its prospects for the future, and if that makes me a lobbyist in the eyes of some, so be it.  I also intend to focus on the issues and not the personalities or motives of people on various sides of the nuclear issue, and if that makes me a person who "projects her natural integrity onto others who do not deserve it," I'll take that as a compliment.


Saturday, April 6, 2013

Natural Gas:

A Flash in the Pan?

Several articles have been published in the past few days all addressing various aspects of the sudden rise in the prospects for natural gas, and the potential longer-term consequences of following policies that rely too much on what might be a short term availability.

The articles take somewhat different approaches to the problem.  Some of the authors, or the analysts cited, have their own biases as far as the alternatives to natural gas.  However, all have some common themes with respect to the long-term prospects for natural gas and the detrimental consequences they can wreak on other alternatives while the costs are low and everything looks rosy.

Two of the articles sum up the key issues:

Is Natural Gas the Next Bubble?  Has Fracking Promised More Than It Can Deliver?

The provocative title is a summary in itself.  The subtitle to the article succinctly states the conclusion:  New research shows that putting too much of our eggs into this energy basket could be detrimental to our future economic health.

The article goes on to provide several examples, for both coal and nuclear plants, where the cost competition from currently cheap natural gas is driving utilities to close the existing plants.  Although I take issue with their characterization of nuclear power as having "glaring environmental, safety and health issues," the authors are objective enough to recognize that substituting natural gas for nuclear power production has serious detrimental effects on carbon emissions.

Based on my own reading, I think their conclusions about the potential short-term nature of the natural gas boom are valid.  They provide a fairly detailed discussion of studies that verify the concerns, and speculate that, in the not-so-distant future, we may find ourselves facing exactly the same scenario that we face today with crude oil--"much more dependent and at a higher price."

Rise of Natural Gas May Mean Fall of Alternative Energy

This article reiterates the theme that the low cost of natural gas may be temporary.  The article also outlines various other concerns about natural gas, including the environmental effects of gas production.

The author outlines some of the paths that the current push for natural gas might lead us down.  He observes that, "Today the shift to natural gas in electricity generation is out-of-control, and consumers are going to suffer as a result. If you want to see the price of natural gas rise significantly, replace all coal and nuclear plants with natural gas over the next 30 years. We would wind up with a single fuel for electricity production just as we have one fuel for transportation. Consumers would regret it."

Although "alternative energy" for many people seems to be a code-word for "not nuclear," this article takes a broader view.  The author notes that:  "Advances in nuclear power and renewable energy sources would help maintain energy diversity. Small modular reactors built in a factory for a fraction of the cost of large nuclear plants could make a real difference in this country and globally. As we expand the use of intermittent renewable sources of electricity - especially solar and wind - base-load nuclear power will be needed to "firm" renewable sources when they are not available."

Other Articles

Still other recent items look at the same problem from other angles.  One, for example, notes that many wind farms have long-term power purchase agreements (PPAs).  These could keep costs low
and exert a downward pressure on rising gas prices.  While the article is focused only on wind, the same should, of course, be true of PPAs for other energy sources.  I am not sure what the terms are for PPAs, so wonder if these could possibly hold prices down for the longer term, but it may be one way we can buy time as the full dimensions of the gas bubble begin to take shape.