Saturday, November 27, 2010

Post # 23: Sustainable Coal ?

Sustainable coal?  Clean coal?  King Coal !

The December issue of The Atlantic magazine has an interesting and challenging article ( http://www.theatlantic.com/magazine/archive/2010/12/dirty-coal-clean-future/8307/ ) that I find at once accurate, balanced, troubling, and angering.  The article is by global- and (especially) China-watcher, James Fallows.  Fallows begins by reviewing the consensus facts regarding the current and recent trend in global carbon emissions (37 billion tons of carbon dioxide per year) and atmospheric carbon dioxide levels (~ 280 ppm).  He next shifts to giving a high-level factual account of the role coal plays in U.S. world-wide energy production.  (Coal-fired power plants are responsible for ~ 46% of the total U.S. electricity production.)

He then states what should be obvious to almost everyone:  the role that coal plays in global energy production is unlikely to change dramatically over the next several decades regardless of the onward-march of technology in the energy conservation, renewable energy, and nuclear energy arenas.  This because there is so much of it, it is relatively cheap, and is likely to remain so for the foreseeable future regardless of rather feeble (to date) attempts by various entities to internalize the external costs of the black commodity.

Next is a quick review of the options for cleaning-up coal:  burn it more cleanly, and capture the carbon after it is burned but before it is released to the atmosphere.  Nothing new here.

Fallows now turns to the element of the article I find most encouraging and at once, most frustrating... the fact that governments around the world (particularly in the West) are failing to make significant advances in improving coal technology because they are no longer places were "doing is done".   We aren't building new power plants in the U.S.  Thus the U.S. isn't a viable test and demonstration platform for new technologies.  Fortunately, China is such a place.

Lastly, a hopeful element to the article... businesses are doing what governments can't seem to pull-off.  "B-to-B" alliances are forming between the U.S. and China, that are beginning to have impact in the deployment of improved energy technologies.  New technologies are being deployed in China, and U.S. businesses are learning lessons they cannot learn in the U.S. because we aren't building anything here.  Fallows highlights Duke Energy Company in Charlotte as a forward-looking company who has become a leader in U.S. engagement in "the doings" in China.

Congratulates to Duke Energy.  Let's hope more companies will follow suite...

Sherrell

Saturday, October 30, 2010

Post # 22: Imperative 4 – Achieving Sustainable Nuclear Fuel Cycles

The fourth Nuclear Energy Imperative has to do with achieving sustainable fuel cycles.

First, let me address my view of the definition of "sustainable".  This actually is not a simple matter.  Many definitions have been offered and there's endless debate about the meaning of this term.  To me, something is sustainable if it does not exhaust fundamental natural resource limits and conveys benefits now and to future generations commensurate with it's costs (economical, environmental, social/cultural).  Sustainability is a benefit/cost issue.  Inter-generational equity is a critical consideration.  Thus, there is also the question of the timeframe over which one performs this assessment.  Is it 100 years, 1000 years, 10,000 years, "forever" ?  From a practical standpoint, given the limits of human knowledge and the progressive nature of science and technology, I tend to adopt the "few hundred years" timeframe for my consideration of such matters.  So let's pick 300 years as the time frame for our analysis.  That's roughly ten human generations.

Second, it's important to have a context for the amount (volume) of spent nuclear fuel currently generated by the nuclear power industry.  As I've noted before, a single 1 Gigawatt electric nuclear power plant produces about 20 metric tons of spent nuclear fuel a year.  That's about forty or so nuclear fuel assemblies for pressurized water reactors.  The entire of inventory of spent nuclear fuel generated in the U.S. today by every commercial nuclear power plant that has every operated can fit in a spent fuel pool less than 300 feet on a side.  (We are NOT generating mountains of spent nuclear fuel in this country.)

My definition of a "sustainable nuclear fuel cycle" is encompassed by five criteria which I term my:

"Five Pillars of a Sustainable Nuclear Fuel Cycle":

  1. known uranium resources would support it's deployment for at least 300 years (300 years from above definition of sustainability);
  2. it would be "affordable" and economically competitive to nuclear power produces and energy consumers;
  3. it would not create unacceptable quantities (volumes) of nuclear waste;
  4. the radiotoxicity (health risks) of the spent nuclear fuel and fuel cycle wastes would drop to levels similar to that of uranium in the earth's crust after a relatively short period of time which is meaningful in terms of human social, cultural, and government structures;
  5. its deployment would not present unacceptable dangers from the standpoint of nuclear proliferation.
An exhaustive analysis of these issues is well beyond the scope of a blog posting, and much research has been done and is currently underway around the world today.  So just a few comments here...

The amount of uranium "economically" recoverable (Pillar 1) is a matter of some debate and uncertainty.  However, given current projections for world-wide growth in nuclear power, it appears we have or will have access to uranium reserves sufficient for somewhere between 100 and 300 years even if the current once-through open fuel cycle continues to be used.  So, from the resource utilization standpoint, the current once-through fuel cycle isn't sustainable.  Additionally, the current fuel cycle creates wastes (that violate my Pillar 4 above.  So the current open fuel cycle is not sustainable and must eventually be replaced.  However, we clearly have some time to land upon the solution.  (See MIT's recent update of their 2009 fuel cycle study.

So what is my proposed solution?  I believe the "solution" is to develop a nuclear fuel cycle (a suite of reactors, nuclear fuels, and nuclear fuel reprocessing technologies) that achieve my Five Pillars with the added specificity that the time frame for application in Pillar # 4 is 300 years (again ~ 10 generations).  I'm not the only one thinking this way.  Dr. Kathryn Jackson's testimony before the President's Blue Ribbon Commission on America's Nuclear Future this past August promoted a similar view from a leader in the nuclear industry.  Dr. Jackson is Westinghouse Nuclear's Senior Vice President and Technology Officer.

As I said, there's much more here to be discussed.  But for now, let's think about the Five Pillars of a Sustainable Fuel Cycle, and the Five Imperatives of Nuclear Energy as a framework for workable nuclear energy future – here and abroad.

More on the proliferation issue (Imperative 5) soon...

Cheers !

Sherrell

Colossians 1:17

Saturday, September 18, 2010

Post # 21: Imperative 3 – Enable the transition away from fossil fuels

Today, approximately 40% of our nation's carbon emissions stem from the use of fossil fuels in the transportation sector (principally liquid fuels production and consumption), and industrial sector (principally fossil-derived process heat production).  Indeed, my own model indicates that even if we completely decarbonized our electricity production, by mid century our total national carbon emissions would drop by less than 25%!

Imagine that!  If not one kilogram of carbon dioxide was released in the production of electricity in 2050, we still would only achieve modest reductions in overall greenhouse gas (GHG) emissions.  Why?  If the population continues to grow at a modest 0.6% per annum, and all these people still drive automobiles, and we still move freight across our country in the same manner, and still provide process heat to our factories in the same manner, we are only addressing 60% of the problem when we focus on electricity production and use.

Improvements in the efficiency of production and use of electricity are already effectively accounted for in my simple analysis.  So, the only way to further improve our lot and achieve more-sizable reductions in our GHG emissions is to transform the transportation and process heat sectors.  We must reduce the consumption of petroleum in our vehicles and the use of oil, coal, and natural gas for production of industrial process heat.

Thus the challenged posed by President Obama's goal of an 80% reduction in carbon dioxide emissions is daunting - to say the least.  In fact, I feel confident in saying the Administration's goals for greenhouse gas emissions reductions are virtually impossible without a revolutionary change in our society.

There are many who believe these energy challenges will drive almost unimaginable changes in population distribution. Interestingly, opposing arguments can be made with regard to the direction of these changes.  Some who have studied this issue believe we will see a massive centralization of our population in urban centers to reduce the transportation costs and petroleum consumption associated with daily commutes to work.  Others feel the opposite will happen – that things will become so dire, our socio-economic infrastructure will collapse, resulting in a return to an agrarian economy.  This belief is normally associated with the assumption there would be a mass exodus from population centers into the suburbs and country side.

There is another solution with five ingredients:
  1. Electrification of the private vehicle and over-road freight transportation sectors (probably requires a major breakthrough in battery technology);
  2. Switching to synthetic fuels where vehicle electrification is not possible;
  3. Switching away from fossil-derived process heat in industrial sectors (especially the petro-chemical sector);
  4. Increasing the size of the nuclear electric power plant fleet and improving the electric grid as necessary to deliver the electricity required for # 1; and
  5. Developing and deploying a new generation of high-temperature and very-high-temperature nuclear reactors to provide the process heat needed to enable # 2 and #3.
This "simple" formula – electrify the transportation sector and produce the electricity with nuclear power plants, and switch to nuclear-derived process heat across our major industrial sectors – would enable the continuation of life as we know it in the western world.  I am not aware of another strategy that is as practical and easily implemented as this approach.  Frankly, absent this approach, or something very similar to it, things look pretty grim...

Just thinking...

Sherrell

Tuesday, July 20, 2010

Post # 20: Imperative 2 - Improving the affordability of nuclear energy

The second of the "Five Imperatives of Nuclear Energy" is: we must improve the affordability of nuclear energy and nuclear power plants.  I'll discuss that today...

Once the construction cost of a nuclear power plant is fully amortized (ie., the "construction loan" for the plant is paid-off), nuclear power plants produce extremely cheap electricity.  The typical cost of electricity production in today's nuclear fleet is less that 3 cents per kilowatt-hr of electricity produced.  In my part of the country (TVA service area), residential electricity sells for about 8 cents per kilowatt-hr – cheap by national standards.  Since most plants are "paid-off" within twenty years, nuclear power plants that are more than about 20 years old are tremendous revenue producers for their owners (you and me if we happen to own stock in a company who owns and operates such a plant), and a source of very affordable electricity for their customers (again... you and me).

While the details of the affordability issue can be complex, at a high-level these issues reduce to three primary factors that have driven the purchase cost of modern nuclear power plants out of the "affordable" range for many prospective buyers:


  1. Todays plants are large (typically greater than 1 GWe in size).  Due to "economy of scale" considerations, the nuclear industry evolved to a "one size fits all" mentality in which the one size was a hugh plant.  Too bad if you really didn't need all of that electricity production capability in one incremental addition.
  2. Like all large, complex facilities,  these large plants require vast quantities of steel, concrete, wire, and other construction materials, along with extensive labor to design and build the plants.  Capital cost estimates for current large plant models range from around $4000 per kWe to as high as $8000 per kWe for a complete plant that is fully-integrated into the utility's electric grid.  That's $4-8 BILLION dollars for a single nuclear power plant. Not something you're apt to find in Walmart!
  3. The time period required to build, license, and commission our most recent nuclear plants (7-10 years) resulted in high finance charges for the capital the utilities had to borrowed to purchase the plants.  This protracted time period was in large-part the artifact of an inefficient licensing process that, in practice, made it extremely difficult to predict when a plant would be allowed to start operations and how much finance charges the owner would have to pay in the interim.  Neither financiers or owners liked that situation.

The solutions to these challenges ?


  1. One of the most exciting developments in this regard is the mushrooming interest in small modular reactors (SMRs).  These plants, ranging in size from as little as 10 MWe to around 300 MWe, would significantly reduce the "single purchase" cost of plant due simply to their small size.  Additionally, many of these plants have features that should enable more automated fabrication and construction, offering the potential to reap the benefits of high-volume "factory fabrication"and simplified field installation.
  2. During the past several years, the U.S. Nuclear Regulatory Commission has reformed and modified it's design certification and plant licensing process.  While maintaining a sharp focus on assuring the safety of new plants, the reformed process should provide a more predictable and accelerated licensing process compared to that experienced in the last several plants built in the U.S.  twenty-some years ago.
While there are a number of other relevant factors and dynamics in play, the advent of small nuclear power plant options, and (hopefully) a more reliable licensing process, should go a long way toward achieving Imperative 2.

Next time, Imperative 3.

Cheers,

Sherrell,  Col 1:17

Wednesday, July 7, 2010

Post # 19: Imperative 1: The Anchor of a Sustainable Energy Future

In Post #18, I introduced the concept of the Five Imperatives of Nuclear Energy.  Briefly, these Five Imperatives are:

  1. Extend the life, improve the performance, and sustain the health and safety of the current commercial nuclear power fleet;
  2. Improve the affordability of nuclear energy;
  3. Enable the transition away from fossil fuels in the transportation and industrial sectors;
  4. Achieve sustainable nuclear fuel cycles;
  5. Assure the deployment of nuclear power systems does not result in the proliferation of nuclear weapons.
Today I will briefly discuss Imperative 1.

Every year since 2005, the U.S. commercial nuclear fleet of 104 operating reactors has produced approximately 4 billion megawatt hours of ultra-low-carbon electricity .  This is 70% of our nation's low-carbon electricity.  According to statistics from the Nuclear Energy Institute, the U.S. nuclear fleet provided this energy while enabling us to avoid the annual production and release of ~ 52 million short tons of sulfur dioxide, 20 million short tons of nitrogen oxides, and 647 million metric tons of carbon dioxide that would have been released into the environment had the same amount of electricity been produced by fossil-fueled power plants in the regions where the plants operate.  In exchange for the electricity produced, the fleet produced approximately 2200 metric tons of used nuclear fuel.  This amounts to around 4400 fuel assemblies, each 12-14 feet long and about 8 inches square - not a large volume of "waste" for the tremendous amount of low-carbon electricity provided.  It would all fit into a box 15 feet high by 67 feet on a side if stored as we store used fuel today.

Every credible low-carbon energy scenario I have seen depends on and is anchored by the assumption our current nuclear fleet continues to operate well past the original 40 yr. license period of the reactors.  I'm convinced significant reductions in our carbon emissions rates are impossible unless we maintain the health and extend the operational lifetimes of these workhorses of clean energy, and supplement them with as much wind and solar energy we can produce.

Thankfully,  at this point, 59 of the 104 operating U.S. nuclear power plants have been grated 20-year license extensions, 20 additional units have filed applications for a license extension, and  19 additional units have indicated they will file for a license extension (total = 98 units).  

The next question is, "how long can these plants continue to safely operate?"  The U.S. Department of Energy's Office of Nuclear Energy, the U.S. Nuclear Regulatory Commission, and the Industry are currently partnered in an R&D program called, the "Light Water Reactor Sustainability (LWRS) Program, which has among its goals the development of the science-based understanding of plant aging required to answer this question.  In addition, DOE recently awarded its Nuclear Energy Modeling and Simulation Innovation Hub to the Consortia for Advanced Simulation of LWRs (or "CASL") –  a team led by Oak Ridge National Laboratory.  CASL has among its goals the development of a "virtual reactor" as a tool for exploration of many reactor performance and aging phenomena.

So... it's a good news story... Our commercial nuclear fleet currently operates at over 90% average availability, with a stellar safety record.  It's the anchor of any realistic low-carbon energy production future.  The fleet's operating life is being extended from the original 40 years to 60 years, and intensive research is underway to allow us to maximize  the safe operating lifetimes of the low-carbon work horses.

We'll discuss the other Imperatives in future posts.

Cheers,
Sherrell
Colossians 1:17

Saturday, June 26, 2010

Post # 18: The Five Imperatives of Nuclear Energy

This past week I was on the road.  I attended the American Nuclear Society Annual Meeting in San Diego where I presented a paper entitled, "Fluoride Salt High Temperature Reactors (FHRs) and the Five Imperatives of Nuclear Energy".   The Imperatives are the five nuclear energy objectives I believe the U.S. must achieve in order to secure a sustainable energy future for our country.  The Five Imperatives are:

  1. Extend the life, improve the performance, and sustain the health and safety of the current commercial nuclear power fleet;
  2. Improve the affordability of nuclear energy;
  3. Enable the transition away from fossil fuels in the transportation and industrial sectors;
  4. Achieve sustainable nuclear fuel cycles;
  5. Assure the deployment of nuclear power systems does not result in the proliferation of nuclear weapons.

These Five Imperatives are an integrated framework of outcomes that will assure a long-term supply of safe, secure, affordable, environmentally sustainable nuclear energy for generations to come.  I'll be discussing each of these Five Imperatives in more detail here in future posts.

Cheers,
Sherrell
Colossians 1:17

Saturday, May 29, 2010

Post # 17: The Gulf Oil Leak – A Tragedy In Slow Motion

Like virtually everyone else, I've been watching the unfolding tragedy in the Gulf of Mexico with a growing sense of doom and sickness in my stomach.  The oil has continued to spew at an alarming rate from the twisted remains of the Deepwater Horizon oil rig since the day of the explosion.  It's like watching a tornado destroy you home in super-slow motion.  And it continues.

The cost of the oil rig disaster in human lives (11 prompt fatalities) is terrible.  The ecological cost to our gulf cost is yet to be bounded, grows by the day, and will probably linger beyond my lifetime.  The economic impact on millions of Americans who draw their living from the sea and the vacation industry will likely be profound.

Why did this have to be the case - given the leak occurred ?

There are many avenues of pursuit to address this question, but the one I've been pondering during the past several days has to do with a simple technical reality: if the oil leak where in 200 feet of water, rather than 5000 feet of water, the leak might have been stopped by now.

Access is a prerequisite for remediation.  It would be nice if we could put human divers down there to work the problem.  I'm not a diver, but I understand commercial divers, using the best available equipment, can reach depths of less than 2000 feet and then only for very limited times.  More routine commercial diving is done in waters of less than 300 feet in depth.

It's a given that if one is in the oil drilling business, one must drill where the oil is to be found.  This said, drilling in shallow water is safer than drilling in deep water.  Easier access if things go wrong.  Oil drilling on land is safer still.  Even easier access.  (This does not account for the varying degress of sensitively of the natural environments surrounding drilling operations.)

But most vacationeers who pay a hefty sum for their ocean-front condos are not inclined to favor those places in which the views are dominated by oil rigs.  In this respect, oil rigs share some of the same "vista challenge" issues as wind turbines.

So we can drill in deep water.  Out of sight, out of mind.  And when something goes wrong, it may be devilishly-difficult to correct.  Or we can drill in shallow water.  Fouls our view of that golden sunset, but we can probably fix a problem in 200-300 feet of water.  Or we can drill on land.  Access not an issue,  but many of the remaining desirable drilling sights are in sensitive environmental areas.

As a personal note here, I've always been very circumspect about off-shore oil drilling due to my concerns that something like the Deepwater Horizon disaster might happen.  And I've never embraced drilling in the Arctic National Wildlife Refuge or similar sensitive ecosystems.

Just one more illustration of the complexity of our energy challenges and the difficult choices we must make to tackle them.

Cheers,
Sherrell

Tuesday, May 4, 2010

Post # 16: The Price of Our Addiction To Fossil Fuel

I was listening again tonight to the latest news from the Gulf Coast regarding the evolving consequences of the April 22 explosion at  the Deepwater Horizon oil rig.  The news reminded me of the price we pay for our "addiction" to oil.  While the potential environmental consequences are alarming, it is the human cost that attracted my attention.


Eleven workers were killed in the Deepwater Horizon accident.  The Deepwater Horizon explosion is the deadliest U.S. offshore drilling rig explosion since 1968, when 11 died and 20 where injured in an explosion on a rig owned by Gulf Oil.  The Deepwater Horizon tragedy follows on the heels of a March 2005 explosion in BP's Texas City refinery, when 15 were killed and hundreds were injured.


Then I thought of the tragic loss of 29 coal miners in early April in the Upper Big Branch coal mine explosion in West Virginia.  The Sago mining disaster in 2006 killed twelve miners.  The U.S. coal mining industry reported it's lowest fatality count in history in 2009 when 12 fatalities occurred.  (Historically, China apparently has suffered around 5000 coal mining fatalities every year.)


The extraction and use of fossil fuels is a dirty, dangerous business.


I consulted several sources in an attempt to uncover the mining fatality statistics for uranium mining.  All the sources I consulted acknowledged that uranium mining is much safer than coal mining, but I did not uncover hard statistics of the direct fatalities resulting from the uranium mining enterprise.  I will continue to seek hard data (I'm sure it's available - just couldn't find it conveniently tonight) and I will update this posting when I uncover meaningful data.


I did uncover an interesting (and somewhat controversial) article from the Next Big Thing website (http://nextbigfuture.com/2008/03/deaths-per-twh-for-all-energy-sources.html).  The article presents an analysis of the integrated "life-cycle" fatality rate per TWh of electricity generated from nuclear, coal, wind, and solar energy sources.   (I caution that credible analyses of this type of are devilishly difficult to perform.)   This analysis utilized a variety of data sources and it's methodology is not completely transparent.   So, while I cannot validate or endorse this analysis as authoritative, the results do provide interesting fodder for energy-geek party conversation:


Coal: 163 fatalities per TWh
Rooftop Solar:  0.44-0.83 fatalities per TWh
Wind:  0.15 fatalities per TWh
Hydro: 0.1 fatalities per TWh
Nuclear: 0.04 fatalities per TWh


I'll continue my search for more detailed analyses...


The bottom line?


1.  We pay a high cost in human loss and suffering from our addiction to fossil fuels.
2.  There is no zero-risk energy production technology.  No free lunch.
3.  Energy generation from renewable sources is far superior to that from fossil energy sources.
4.  Nuclear energy is among the most human-friendly, if not the most human-friendly energy production option.


Nuclear energy: a sustainable energy option.

Friday, April 23, 2010

Post # 15: Nuclear Energy As An Enabler of Renewable Energy

I believe the solution to many of our nation's most pressing energy and environmental challenges is more nuclear energy, as much solar and wind energy as we can "tolerate"; a smarter, more robust electrical transmission and distribution system; and electrification of the transportation sector.

I'm all for renewable energy.  Seriously.  Just don't mess-up my view of the mountains, don't kill endangered bats, useful insects, and birds.  And whatever you do – don't dam up my trout stream.

So how much renewable energy (wind/solar) can we integrate into our electrical system?  It turns out we have a few on-going real-world experiments that are giving us some good indicators.  Texas has embraced wind energy in a big way.  Around 9000 megawatts of windpower have been installed in the state.   Sometime back I attended a conference in which a representative from the Electric Reliability Council of Texas (ERCOT) spoke with pride about their success in expanding their wind-turbine-based electrical energy generation.   Then he made the following statement, "We've just about reached the limit of the amount of wind energy generation we can add to the system.  We will have to add more gas turbines or base-load coal or nuclear capacity in order to enable us to increase our wind generation."  The reason?

It turns out that due both to the variability of the wind, and the nature of the electrical generation systems used in today's wind turbines, too much wind energy can actually destabilize an electrical generation system - leading to all sorts of serious problems - including voltage surges, load drops and blackouts.

I guess a good analogy would be to think of two vehicles you might drive.  Imagine one vehicle has a single 200-horsepower engine and a single throttle pedal you control.  Now imagine the second vehicle has one hundred, 2-horsepower engines.  You don't have a throttle pedal for any of them.  Worse yet, each of these one hundred engines runs independently, at varying speeds, on schedules that are very difficult to predict.  Now your job is to drive one of these two vehicles from point A to point B on a fixed schedule.  Which vehicle would you choose?

This (admittedly limited) vehicle analogy illustrates the problem we face as we add more and more wind and solar energy to an electrical grid.  Eventually we lose control and the ability to manage the system.  At some point, the variable nature of the renewable electrical generation overwhelms the predictable and controllable nature of the "base-load" generation and bad things happen.  That point appears to be somewhere in the range of 20 – 30% of the total electrical generation. (Much can also depend on how widely dispersed the wind turbines are in location due to the resultant time variability in generation.)

What do we need to enable us to go beyond 20% renewables?  Well, a breakthrough in energy storage devices for one thing – the ability to stabilize the system by storing the energy being generated that isn't needed on a moment-by-moment basis.  And smarter electrical grids that give us more robust and precise control over both generation and consumption.  Some of our best and brightest are working on these challenges.

So, in the near-term, how do places like Texas add more wind and solar capacity to their generating grid?  By adding more quite, emissions-free base-load nuclear capacity that keeps the percentage of renewables at or below 20% of the total.

So for now, the best "enabler" of renewable energy is .... nuclear energy.

Nuclear and renewable energy - a match made in heaven...

P.S.  For those of you more technically inclined and interested in the subject, a couple of interesting discussions of the Texas wind experience can be found at:

http://www.wind-watch.org/news/2010/04/03/wind-energy-under-fire-within-ercot/

http://www.rice.edu/energy/research/carbonsolutions/Hartley%20Presentation%20Aug09Workshop-SECURE.pdf

Cheers!
Sherrell

Friday, April 9, 2010

Post # 14: Nuclear Waste May Get A Second Life

Nuclear power is the most dependable and economical non-emitting electricity production source available today – accounting for 70% of the non-carbon-emitting electricity production in the U.S.  However, the once-through nuclear fuel cycle currently employed by our commercial nuclear power plants taps less than 10% of the energy value in the fuel.  Reprocessing and re-use of the contents of used nuclear fuel would enable us to significantly increase the fraction of available energy extracted from the fuel and more efficiently utilize the earth's uranium resources.


The goal of nuclear fuel reprocessing research is to develop reprocessing approaches that are economically viable, environmentally acceptable, and secure from the proliferation vulnerability standpoint.


I had an opportunity recently to spend the day with National Public Radio's award-winning science journalist, Richard Harris.  Richard came our way to research the status of nuclear fuel reprocessing research.  His story ran today on NPR's Morning Edition.  You can read and listen to the story at:


http://www.npr.org/templates/story/story.php?storyId=125740818


I think Richard did a nice job of presenting the issues, goals, and challenges associated with harnessing that untapped energy in used nuclear fuel and reducing the burden of the spent fuel and nuclear waste legacy of nuclear power.

Tuesday, February 16, 2010

Post # 13: A Common Sense Victory – The Vogtle Loan Guarantee

President Obama's announcement today that his administration will authorize the first federal loan guarantee for a new nuclear power plant should be a cause for celebration by all who seek a secure, low-carbon energy future for our nation.  The $8.3B loan guarantee for Southern Company's Vogtle project is contingent on NRC approval of the combined construction/operating license for the two AP-1000 pressurized water reactors, and is the first for a nuclear power plant.  This loan guarantee program, originally authorized under the Energy Policy Act of 2005, empowers the federal government to guarantee loans for projects that accelerate commercial deployment of new or improved technologies that will sustain economic grown, yield environmental benefits, or produce a more stable and secure energy future.  Previous loan guarantees have been issued to solar photovoltaic, wind turbine, and and energy storage projects, as well as a carbon manufacturing plant.  Thumbs up to the President !

Saturday, January 30, 2010

Post # 12: Your Life In Uranium and Coal

The average American consumes ~ 14000 kWh of electricity per year - among the highest in the world. That's roughly 1,120,000 kWh of electricity in an 80-year lifespan.

Let's examine how much fuel must be consumed in modern nuclear and coal-fired power plants to produce this amount of electricity – "your life in uranium and coal" so to speak...

Nuclear reactors are powered by fission process  ~ 51000 fuel pins (in a typical gigawatt-class nuclear power plant).  Each of these fuel pins is approximately 1/3-inch in diameter and ~ 12 feet in length (there are many variations, but these are reasonable average numbers.)

Based on the current once-through nuclear fuel cycle (which, by the way, extracts < 10% of the energy that is theoretically available in the fuel), the 14000 kWh of electricity each of us "consume" in a year is produced in only 2.6 inches of ONE nuclear fuel rod!  If you "run the numbers", this means that all of the electricity consumed by one American during their 80-yr life is produced by less than two of these small fuel pins !  In more familiar terms, that's about a soda can of nuclear fuel, or a cube of nuclear fuel a bit less than 4 inches on a side.  How's that for an efficient energy source?

Now compare these estimates to the amount of coal required to produce the same amount of energy.  The average energy content of coal is ~ 6150 kW(t)h / metric ton.  If we assume 40% overall thermal efficiency of the coal-fired plant (generous on average), that same American would consume ~ 455 metric tons of coal.  That's equivalent to a solid cube of coal 135-ft on a side.

So picture this... a soda can of nuclear fuel or a cube of coal 135 feet on a side:


That's "your life in uranium and coal"...

Cheers,
Sherrell

Monday, January 18, 2010

Post # 11: Putting A Lid On Bottled Water ?

Do you ever wonder about the energy consumption and CO2 footprint of a bottle of that cold, clear, water you pickup from the local quick-mart on the way to/from your kid's soccer game?  I became curious about this recently after noticing a beautiful bottle of south-pacific water in my hotel room.


After some digging, I found a very interesting short paper by Gleick and Cooley of the Pacific Institute (http://www.pacinst.org/reports/bottled_water/index.htm) that analyzed this exact question (well.. the energy consumption part of it anyway).  The paper, entitled, "Energy Implications of Bottled Water," is available online at http://www.iop.org/EJ/article/1748-9326/4/1/014009/erl9_1_014009.pdf?request-id=9c25df5f-a5c7-4263-aae2-e12b73d47bb0 .


Gleick and Cooley analyzed three scenarios for bottled water consumed in the Los Angles area: (1) water locally bottled, (2) water bottled in Fiji, and (3) water bottle in France.  The paper concludes that, depending on the bottling location, the energy required to purify, bottle, and deliver 1 liter of cold, clear bottled water to the consumer's lips is between 5.6 and 10.2 MJthermal/liter. (The larger number is associated with water produced in Fiji.  The energy demand would be even larger for an east-coast USA consumer.


According to Gleick and Cooley, the US consumed approximately 33 million liters of bottled water in 2007.  So if we extrapolate to the total effective energy required to meet the US market, 33E6 liters * 10 MJthermal/liter = 330E6 MJthermal.


The effective carbon footprint of this bottled water depends, of course on the source of the thermal energy.  If we assumed ALL of the energy required came from coal, and assuming a conversion factor of ~ 0.38 kg CO2 / MJthermal, the total CO2 footprint of our bottled-water addiction is approximately 330E6 MJthermal * 0.38 kg CO2 / MJthermal = 125,400,000 kg CO2 or 125,400 MT CO2.  Recalling our total annual US CO2 emissions is approximately 6,000,000,000 MT  CO2, this represents approximately 0.002% of our total annual CO2 emissions.


Significant?  You be the judge...


Cheers,
Sherrell


Tuesday, January 12, 2010

Post # 10: A Home For Life: Dynamic Energy-Sensitive Housing

My wife and I are at the stage in life where we are looking to "right-size", "down-size", and "optimize" our home.  Our kids are grown and out of the house.  Home functionalities that were important at one point in our life are no longer so important.  Functions we've never really considered important are now becoming important (like living on one floor).  We need to move.

Americans have an almost sacred attraction to the concept of "owning our own home".  Our federal policies promote it, our tax laws enable it, and we are taught from birth that home ownership is a major element of the "American Dream".  Our home also becomes a major element of our personal financial worth as we move through life.

But, in a mobile society, home ownership can also impede the periodic relocations that are becoming the norm in today's world.  Further, in a world of limited energy resources, living in a home that is larger than we need is a wasteful.

Our housing needs (size and type of space) change as we move through life.  A single person becomes a couple.  A couple becomes a family.  A family becomes a couple, and often, a couple becomes a widow or widower.  The mobility of youth is traded for the fragility of old age.

This got me to thinking...

What if we pursued a very different approach to home ownership?  Imagine a model in which you purchase the land upon which you will live, but then had the option to add, in a modular fashion, the space you need as you need it, and reduce the space you no longer need as your needs diminish.

How might we accomplish this?

Imagine inter-connecting standardized panels for floors, walls, ceilings, and roofs.  When you need more space (extra bedrooms, bathrooms, etc), you run down to the local Home Depot and purchase more panels or modules.  When you no longer need that second story, that extra bedroom or bath, or that extra garage space, you conveniently disassembly the unneeded modules, truck them back to the local "housing" co-op, and sell them  Voila!  Less space to clean, less space the heat and cool, and a less real estate tax to pay!

How would such a model impact our society and our culture?  Our lifetime energy consumption?  Personal wealth strategies?  Worker mobility?  Community stability?  Governmental fiscal policies,  our banking system, etc.?

My guess is the impacts would be profound in ways we can predict, and in some we cannot.

Imagine...

Cheers,
Sherrell

Thursday, January 7, 2010

Post # 9: Disruptive Technologies and Our Energy Future

I have long been intrigued by the phenomenon of "disruptive technology" (DT). The term was originated by Clayton Christensen in the mid-1990s. Put simply, disruptive technology (also referred to as "disruptive innovation") is a technical innovation that profoundly changes society by providing either a paradigm shift in functionality, delivering existing functionalities at dramatically lower cost than current options, or extending functionalities in to new markets and cultures.

DTs are usually unexpected by the market, and often (but not always) accompanied by rapid rates of societal adoption and market penetration. Recent examples of DT include digital photography, iPods, and cell phones (now merged in many platforms). Other examples might include LEDs, transistors, internal combustion engines, the telephone, the telegraph, and (no doubt) the wheel.

I've given some thought to a "wish list" of disruptive energy technology innovations that would fundamentally change our world and our energy/society/environment dialog. Some of these DTs are in the energy supply sector, some in energy distribution, and some in energy use.

So here goes, "Greene's Wish List of Disruptive Energy Innovations"

1. Carbon capture and storage: Effective, economic carbon capture and storage technologies. This innovation opens the door to continued use of fossil fuels. ScottishPower recently announced a "breakthrough" in carbon capture - 90% carbon capture with a 1/3 reduction in energy consumption relative to current best practice. (See: http://www.energyefficiencynews.com/power-generation/i/2620/) However, the cost of this technology is still undesirably-high, and then there's the possibly more difficult issue of what to do with all that carbon once you've captured it. (There's got to be a Nobel prize in this for someone.)

2. Energy Storage: Deep-cycle battery or other electrical energy storage technologies with 10 times the current energy storage densities of consumer batteries. Today's lithium-ion batteries are at ~ 0.5 MJ/kg. So we're going for ~ 5 MJ/kg. (Recall crude oil is about 50 MJ/kg energy content. So even such a revolutionary change as I'm describing here would still only move "man-made" energy storage to 10% of that found in nature.) Such technology would open the door to greater production and use of wind and solar electricity, and major reductions in petroleum consumption in the transportation sector by enabling wide-scale adoption of electric vehicles. Without this, it's difficult to see how wind and solar can ever provide more than 25-30% of our electricity because of their destabilizing impact (time and frequency domains) on the grid. An interesting recent (brief) overview by House and Johnson can be found at: http://www.thebulletin.org/web-edition/columnists/kurt-zenz-house/the-limits-of-energy-storage-technology. A second Nobel for someone.

3. Energy Conservation: Heating and cooling of buildings accounts for almost 40% of total U.S. primary energy consumption. I'm thinking user-installed, mass-market (think Home Depot and Lowes), low-cost, technologies to reduce residential and commercial energy consumption. How about attractive insulating panels that could be backfit to the interiors of homes and office buildings to cut through-wall energy-loss by 50%?

4. Energy Production: Flexible, low-cost, super-efficient solar-PV panes for roof-top (and other surface) mounting. I'm talking efficiencies > 40% at mass-market (think Home Depot and Lowes) prices. Today's best multi-junction concentrating solar cells have run at ~ 40% efficiency in idealized laboratory tests. Moving this efficiency into affordable mass-market products would be revolutionary. There is hope. Researchers at Idaho National Laboratory have recently developed a "nanoantenna" technology that might someday achieve efficiencies as high as 80% according to their reports. See: https://inlportal.inl.gov/portal/server.pt?open=514&objID=1269&mode=2&featurestory=DA_101047

5. Energy Production: Small (say 100 - 300 MWe), high-temperature (800-900 C) nuclear process heat and electricity systems. I'm talking factory-fabricated power and process heat systems for less than $2B/kWe. These affordable high-temperature systems will enable 50% efficient electric power conversion systems and high-temp process heat for a wide variety of industrial uses.

These five Disruptive Innovations would fundamentally change the nature of our energy/environment challenge, reduce global greenhouse gas emissions, and improve the energy security of the U.S. It is an interesting reality that most of these "wish list" items will require solution to long-standing challenges in the materials engineering and science arena.

Let's get cracking ....


Sherrell


Monday, January 4, 2010

Post # 8: The Carbon Footprint of Electricity Production

I've been searching for credible information on the "life-cycle" carbon footprint of electricity generation from different sources. By "life-cycle", I mean the total effective carbon footprint ( CO2 emitted / unit of electricity generated) including resource extraction, power plant and equipment manufacturing and construction, and power production operations. Reliable information is difficult to come by - principally because it is devilishly hard to calculate these life-cycle CO2 footprints in a consistent manner.

The five studies I've chosen to summarize here are referenced at the end of this post. The studies were conducted by a variety of organizations for different purposes over a 9-year period between 1998 and 2006. I've summarized the results of the five studies in the graphic below, which displays the range and the average value of the emissions estimates from the five studies for each of the generation types. All generation types were not evaluated by each study, and in some cases (Wave/Tidal and Oil) only point estimates were give. (Note to reader: g CO2/kWh = kg CO2/MWh = MT CO2/GWh). You'll probably need to click on the image to see the expanded version if you want to read the values from the chart.

Several conclusions can be drawn from the chart above and from a more detailed review of the actually reports from which the data are taken:

(1) there is no significant difference between the life-cycle carbon footprint of hydro, nuclear, and wave/tidal power; and all three electricity generation sources are substantially better (by two orders of magnitude or more) than coal and natural gas.

(2) wind and biomass have ~ twice the CO2 emission footprints of hydro, nuclear, and wave/tidal - but still far superior to natural gas, coal, and oil

(3) solar-PV appears to have a significantly higher CO2 emission footprint than hydro, nuclear, wave/tidal, wind and biomass. There's some interesting details in the analysis. While the majority of studies place it's CO2 footprint near that of hydro, nuclear, and wave/tidal, some studies estimate a significantly higher footprint (hence the range shown the plot). Some of this may be due to different assumptions regarding the specific solar-PV technologies employed, differing assumptions regarding the deployment location of the solar-PV systems,and some may be due to the specific analysis methodologies employed.  I find it difficult to believe solar-PV's CO2 footprint could be even close to that of natural gas, but I need to understand this better.

(4) the three fossil sources (natural gas, coal, and oil) are all problematic unless/until we overcome the carbon capture/storage challenge . Breakthroughs in carbon capture and sequestration technologies for these fossil-driven electricity sources would tremendously improve our chances of achieving the global green house gas emission reductions we need.

Last words... if you're interested in reducing CO2 emissions, and you believe in dealing with the facts, you must give serious thought to the "low-carbon portfolio": hydro, nuclear, wave/tidal, geothermal, and biomass. I'm not putting solar in this category just yet. Solar probably belongs in the low-carbon portfolio, but I want to understand the wide variation in CO2 emissions footprints noted above, before I draw that conclusion..


REFERENCES:

1. "ExtremE - Externalities of Energy. National Implementation In Germany,"Krewitt, Mayerhofer, Friedrich, et al., IER, Stuggart, 1998

2. "Hydropower-Internalized Costs and Externalized Benefits," Frans H. Koch, International Energy Agency (IEA), Implementing Agreement for Hydropower Technologies and Programs, Ottawa, Canada, 2000

3. "A guide to life-cycle green house gas (GHG) emissions from electric supply technologies", Daniel Weisser, PESS/IAEA, IAEA Bulletin 2000

4. "Life-Cycle Assessment of Electricity Generation Systems and Applications for Climate Change Policy Analysis," Paul J. Meier, University of Wisconsin - Madison, August, 2002 (http://fti.neep.wisc.edu/pdf/fdm1181.pdf)

5. "Carbon Footprint of Electricity Generation", Science and Technology Postnote # 268, UK Parliamentary Office of Science and Technology, October 2006 (http://www.parliment.uk/documents/upload/postpn268.pdf)

Friday, January 1, 2010

Post # 7: My 2010 Reading List



I've been giving some thought to my personal reading list for 2010. I have rather eclectic interests and resultant reading habits. (I like classical english novels, a few english-language poets, and the Bible - but that's a different reading list.) When it comes to energy/society/environment issues, I like to read penetrating analysts by broad thinkers - even if I don't agree with them. (Why waste my time only reading authors who think like me?) I believe our reading should stretch us, enrich us, inform us, and stir us to action.

With this as background, here' s my current 2010 energy/society/environment reading list:

The GeoPolitics of Energy: Achieving a Just and Sustainable Energy Distribution by 2040 by Judith Wright and James Conca. I've met Jim Conca. He's an articulate and passionate communicator of our global energy plight, and its connection to quality-of-life issues for the 2/3 of the world population who are suffer through their days and nights with little of no access to energy.

The Long Emergency by James Howard Kunstler: A controversial hit that sparked an intense debated among businessmen, environmentalists, and bloggers when it was published 2005 and 2006. Kunstler is a strong critic of rural sprawl in America, and a strong believer in peak oil. (I'm already into this one...)

Sustainable Energy - Without the Hot Air by David JC MacKay: A recent, very popular book on low-carbon energy options. MacKay is getting high marks for his pragmatic, penetrating analysis of our options.

Whole Earth Discipline: An Ecopragmatist Manifesto by Stewart Brand. Brand is the founder of the Whole Earth Catalog. In recent years, he (like Patrick Moore, the co-founder of Greenpeace) has evolved away from his earlier narrow solution set to our global energy/environment problems, to a broader "portfolio" approach to solving our complex problems.

Blackout by Richard Heinberg. Heinberg is a well-known advocate of our need to move away from fossil energy sources. Has a sharp focus on global, systems-level solutions. From what I know of him, he also has a refreshing tendency not to sugar-coat the warts of any of the energy sources and solutions.

Two books by Vaclav Smil: (1) "Energy in Nature and Society: General Energetics of Complex Systems", and (2) the more recent "Global Catastrophes and Trends: The Next Fifty Years". Smil, a Distinguished Professor in the Faculty of Environment at the University of Manitoba has a reputation as a provocative and thoughtful analyst. However, from my limited exposure to his writings, his position on nuclear energy appears dated and unbalanced. Nevertheless, he tends to be a mind-stretcher.

Guns, Germs, and Steel by Jared Diamond: Pulitzer Prize winning book on the fate of human societies (His more recent book, "Collapse" is one of my favorites.)

A Short History of Nearly Everything by Bill Bryson. Bryson is a great science writer. This book, which was originally published in 2003, is supposed to be one of his best.

A Road More or Less Traveled by Otis & Roberts. A book recently published by two young men who hiked the Appalachian Trail from Maine to Georgia. It's full of hilarious stories, thought provoking introspective, and reflective criticism about our society and our culture. (Yes, I'm already well into it...)

What Jesus Demands From the World by John Piper. Piper is one of my favorite modern Christian writers. Always thought-provoking, hard hitting, and always focused on bringing the reader to a personal engagement with Jesus Christ and personal obedience to His Word.

I told you it is an eclectic list .... :)

Cheers, and Happy New Year!
Sherrell