Tuesday, January 27, 2009

How long will uranium last?

Ten countries responsible for 94% of the world's uranium supplies.
And then there are the oceans.

Scientific American recently posted a very interesting online article about future uranium supplies for nuclear reactors. I wrote a blog article about this subject last year on New Papyrus ( Fueling our Nuclear Future).

But to quote from the SciAm article "If the Nuclear Energy Agency (NEA) has accurately estimated the planet's economically accessible uranium resources, reactors could run more than 200 years at current rates of consumption."

The article further states "Using more enrichment work could reduce the uranium needs of LWRs by as much as 30 percent per metric ton of LEU. And separating plutonium and uranium from spent LEU and using them to make fresh fuel could reduce requirements by another 30 percent. Taking both steps would cut the uranium requirements of an LWR in half."

And finally the article states "...the extraction of uranium from seawater would make available 4.5 billion metric tons of uranium—a 60,000-year supply at present rates. Second, fuel-recycling fast-breeder reactors, which generate more fuel than they consume, would use less than 1 percent of the uranium needed for current LWRs. Breeder reactors could match today's nuclear output for 30,000 years using only the NEA-estimated supplies."

Links and References

1. How long will the worlds uranium supplies last?
Scientific American

2. Fueling our Nuclear Future
New Papyrus

3. Supply of Uranium
World Nuclear Association

Thursday, January 22, 2009

The Big Energy Gamble

If you didn't get a chance to see the PBS NOVA program 'The Big Energy Gamble' about the state of California's pursuit of a clean energy economy, you can watch this very interesting documentary on line at the PBS website at:


It features Governor Arnold Schwarzenegger and America's new Energy Secretary, Steven Chu.

Hasta la vista, baby!

Monday, January 19, 2009

Congratulations Mr. President

Here are three of my favorite Barack Obama music videos. Congratulations to the new president of the United States of America! Hopefully this will be the beginning of a new American scientific and economic renaissance!

Marcel F. Williams

The Mission - The Mission Riddim

Viva Obama!

Super Bowl Rock!

Wednesday, January 14, 2009

The Relative Safety of the New Generation of Nuclear Reactors

by Marcel F. Williams

The Chernobyl nuclear disaster occurred on April 26th, 1986 when reactor number four at the Chernobyl electric power facility in the Ukraine had a chemical explosion. Human error combined with the poor construction and design of the facility caused the chemical explosions and fires that released a plume of highly radioactive fallout into the atmosphere. Thirty-five people who attempted to put out the fires at Chernobyl died shortly after the accident of radiation poisoning. However, the immediate evacuation of about 116,000 people from areas surrounding the reactor reduce the general population from exposure to high levels of radiation. A United Nations report determined that a total of 57 people died as a direct result of the radiation from the disaster. Additionally, the UN study predicted that over several years up to 4000 additional deaths could result from radiation exposure from Chernobyl. However, the latest UN report suggest that these numbers may have been overestimated. Additionally, the IAEA reports that there has been no solid evidence of any additional deaths related to the Chernobyl disaster.

It should be noted that the Ukraine has lost hundreds of people since the Chernobyl disaster, deaths not due to the nuclear industry but due to coal mine disasters. In China, more than 44,000 people died in coal mine diasters from 2000 to 2007. Even in the US, over 800 people died in coal mines from 1980 to 2007. Additionally, it is estimated that coal pollution kills over 30,000 people annually in the US and over 170,000 people worldwide die annually because of coal pollution.

Seven years before the Chernobyl nuclear accident, there was a core meltdown at Unit Two at the Three Mile Island nuclear power facility in the United States. However, contrary to Chernobyl, no member of the public was injured during the accident. That's because nuclear reactors in the US are safely housed in containment structures. The off-site radiation exposure during the Three Mile Island accident was 0.46 mSv which is substantially lower than a gastrointestinal X-Ray (2.2 mSv). About 50 mSv is the lowest dose at which there is any evidence of cancer being caused in adult human beings.

It should be noted that humans expose themselves to their own natural radiation, from the radioactive potassium in their bones, at about 0.39 mSv annually. Exposure to cosmic radiation in the US can range from 0.35 mSv to 1.2 mSv annually and exposure to terrestrial radiation can range from 0.30 mSv to 1.15 mSv. Additionally, humans are also exposed to an average of 2.0 mSv from radon in the atmosphere annually.

But when it comes to man made disasters in the 20th century, even the worse nuclear accident in human history is dwarfed by several other human caused events:

On December 20, 1987, the Philippine- registered passenger ferry, the MV Dona Paz, sank after colliding with the MT Vector oil tanker resulting in more than 4000 deaths. We all remember the substantial loss of life aboard the Titanic back in April 1912, but this is cited as the worst peace-time maritime disaster in history.

In response to a fog induced cold snap in London back in December of 1952, the people of London began to burn a lot more coal. This resulted in polluted air being trapped by an inversion layer formed by the dense mass of cold air. The 'Great Smog' initially killed some 4000 people with an additional 8000 dieing several months later.

The Bhopal India chemical disaster started on December 3rd, 1984. A Union Carbide subsidiary accidentally released 42 tonnes of toxic methyl isocyanate (MIC) gas from a pesticide plant. More than 8000 people died within two weeks time. Some estimate the people still suffering from this disaster may raise the death toll to over 15,000 people.

On August 8th, 1975, the breach of the Banqiao Dam in China released 700 million cubic meters of flood water in just 6 hours, wiping the Daowencheng Commune completely off the map, killing all 9,600 of its citizens. Approximately 26,000 people died from the flooding and an additional 145,000 died from the resulting famine and epidemics in the Henan Province area. 5,960,000 buildings collapsed affecting 11 million residents.

Now that the US and the world is experiencing a new energy and climate change crisis, nuclear power is being looked at as a possible long term solution to our energy and environmental problems. But how safe are current nuclear reactors? And how safe are the new generation of fission reactors such as the NRC certified AP1000?

The frequency in which a single nuclear reactor is likely to experience damage to its core (a nuclear meltdown) is referred to as "core damage frequency". The frequency in which a single nuclear reactor with a containment structure is likely to expose the surrounding environment with significant amounts of radioactive material after a major core damage event is referred to as "large release frequency".

There are less than 450 commercial nuclear reactors currently operating in the world. But what would the relative safety consequences be if our planet-- dramatically increased-- the number of fission reactors? What are the statistics?

Frequency of Core Damage in Current US Nuclear Reactors
(2 × 10−5 reactor years)

1 reactor -- once every 50,000 years
10 reactors -- once every 5,000 years
100 reactors -- once every 500 years
1000 reactors -- once every 50 years
10,000 reactors -- once every 5 years

Frequency of Core Damage for ABWR
(2 x 10-7 reactor years)

1 reactor -- once every 5 million years
10 reactors -- once every 500 thousand years
100 reactors -- once every 50,000 years
1000 reactors -- once every 5000 years
10,000 reactors -- once every 500 years

Frequency of Core Damage for ACR 1000 (CANDU)
(3 x 10-7 reactor years)

1 reactor -- once every 3.3 million years
10 reactors -- once every 330 thousand years
100 reactors -- once every 33,000 years
1000 reactors -- once every 3300 years
10,000 reactors -- once every 330 years

Frequency of Core Damage for ESBWR
(3 x 10-8 reactor years)

1 reactor -- once every 33 million years
10 reactors -- once every 3.3 million years
100 reactors -- once every 33o,ooo years
1000 reactors -- once every 33,000 years
10,000 reactors -- once every 3300 years

Frequency of Core Damage for AP 1000
( 5.09 x 10-7 reactor years)

1 reactor -- once every 2 million years
10 reactors -- once every 200,000 years
100 reactors -- once every 20,000 years
1000 reactors -- once every 2000 years
10,000 reactors -- once every 200 years

Frequency of Large Release of Radioactive Material for AP 1000
(6 x 10-8 reactor years)

1 reactor -- once every 17 million years
10 reactors --- once every 1.7 million years
100 reactors --- once every 170 thousand years
1000 reactors -- once every 17,000 years
10,000 reactors -- once every 1700 years

There are slightly more than 100 commercial nuclear reactors in the US. And all were upgraded for safety after the Three Mile Island incident . So at current power production levels, the probability of another meltdown in the US would be one in 500 years. And if we conservatively assume that a large release of radiation due to containment structure failure might occur perhaps once in every 5 core damage incidents, then we could expect the general public in the surrounding environment might be put in danger, once every 2500 years.

But as shown above, the safety of the new generation of reactors has been substantially improved. So that even if we powered our entire human civilization with about 10,000 AP 1000 (1,100 MWe) nuclear reactors, we could expect a meltdown just once every 200 years with a significant breach of containment occurring just once every 1700 years. And if Chernobyl is the best example of the worse case scenario for commercial nuclear power then we can expect less than 60 people will die when such a breach of containment does occur perhaps a few thousand years from now. Wow!

Possible future commercial reactors such as the Pebble Bed Modular Reactor (PBMR) and subcritical reactors like the ADS (Accelerator-Driven Systems), of course, would have a zero possibility of meltdowns. And such inherently safe reactors could compliment or eventually replace some of the new extremely safe reactor systems within the next 20 or 30 years.

References and Links

1. G. Olah, A. Goeppert, and G. Prakash, (2006) Beyond Oil and Gas: The Methanol Economy, Wiley-VCH Verlang, Weinheim, Germany

2. AECL ACR-1000 - Technical Report

3. AP 1000

4. Nuclear Safety

5. Three Mile Island Accident

6. Chernobyl disaster

7. U.S. coal mining deaths: 1990-2007

8. The Catastrophic Dam Failures in China in August 1975

9. After 30 years, secrets, lessons of China's worst dams burst accident surface

10. Subcritical Reactors

New Papyrus 2009

Saturday, January 3, 2009

Mining the Moons of Mars

by Marcel F. Williams

Moving towards a non carbon dioxide polluting energy economy does face a few problems as far as natural resources are concerned. Without breeder technologies, nuclear power faces the problem of limited terrestrial uranium resources. However, if emerging technologies designed to extract uranium from seawater come into fruition then there could be enough marine uranium resources to power all of human civilization for over 3000 years-- even without the reprocessing of spent fuel or the use of breeding technologies.

The new electric vehicle (EV) and plug-in hybrid vehicle (PHEV) technologies face the problem of limited lithium resources for their electric batteries. Here too, emerging technologies to extract lithium from seawater may be a partial solution. But PHEVs may have to fall back to using nickel-iron batteries in order to deal with the lithium shortage. This would reduce the projected range of these vehicles during electric mode to just 20 or 30 kilometers per charge instead of the 60 kilometer range, if billions of people on Earth are going to have access to these partially electric vehicles. The range for commuters could be doubled if they were able to recharge their vehicles again in cities that have recharging units located at every parking spot or parking lot in a city. That would be a very good infrastructure investment for the new Obama administration.

But its clear that synfuels are going to have to make up the brunt of power for the next generation of ground vehicles. Liquid fuel efficiency could be substantially increased, however, if future ground vehicles used methanol fuel cells. According to the Department of Energy, urban and rural biowaste in the US has the potential to produce up to 30% of our current transportation fuel needs within the next 20 or 30 years. But additional hydrogen is going to have to be added to the process if we are to take full advantage of 80% of the carbon dioxide wasted during synfuel production if we are going to completely replace petroleum for our transportation and industrial chemical needs. CO2 extracted from air could also be an additional source of carbon dioxide for carbon neutral synfuel production.

However, renewable sources of hydrogen could be a problem. The electrodes for the electrolytic production of hydrogen from water and the fuel cells required for high efficiency methanol and hydrogen ground vehicles requires-- platinum.

Platinum is an extremely rare metal that is 30 times rarer than gold. It occurs as only 0.003 ppb (parts per billion) in the Earth's crust. If all of the world's gold reserves were poured into an Olympic-size swimming pool, three such pools would be required to accommodate the total gold supply. But all of the world's platinum reserves would not even fill up one such Olympic-sized pool, only coming up deep enough to reach one's ankles.

Platinum currently sells at approximately $27 per gram. And 239 tonnes of platinum was sold in 2006. 80% of that supply came from South Africa with most of the rest coming from Russia and Canada. Approximately 130 tonnes of platinum was used for automobile catalytic converters, a demand that is likely to increase as rapidly growing economies like China and India begin to conform to Western automobile pollution standards. Another 49 tonnes was used for jewelry. The remaining 60 tonnes was utilized for various applications including electronics, chemical catalyst, electrodes, spark plugs and even anticancer drugs.

But if platinum were required for high efficiency fuel cells for automobiles, only 20% of the world's ground vehicles could be supplied. This of course doesn't even include the substantially higher demand for platinum if electrolysis became the primary means for producing hydrogen for a carbon neutral hydrocarbon fuel and industrial chemical economy.

While alternatives to platinum use in fuel cells and electrodes for electrolysis are currently being intensely pursued by researches, it is interesting to note that while platinum is rare in the regolith of Earth, it is extremely abundant in space-- in the form of asteroids. In fact, the largest sources of platinum on Earth occur in regions that appear to have been hit by large asteroid impacts in the more recent geologic past.

The total mass of the asteroid belt between the planets Mars and Jupiter is estimated to be about 3.0–3.6 quintillion tonnes (3.0 t0 3.6 billion billion tonnes of material). If all of this asteroid material were sprinkled over the entire land area of the Earth, it would be approximately 8 kilometers deep. Asteroids on average contain about 15,000 parts per billion (ppb) of platinum vs an average of only 0.003 ppb of platinum found in the Earth's crust.

Planetary scientist, John Lewis, estimated that if all of the total platinum wealth in the asteroid belt were divided amongst every person on Earth, each-- individual's-- share would come out to be over $30 billion. Furthermore, he estimated that if the total value of resources of the asteroids: iron, nickel, aluminum, titanium, gold, silver, uranium, etc. were divided amongst every individual on Earth then each individual's share would come out to be over $100 billion. So its clear that while we may live on a planet of limited industrial material resources, we also live in a solar system of virtually unlimited industrial material resources.

Interestingly, two additional potential sources of asteroid material may be in orbit around the fourth planet of our solar system. Mars has two moons, Phobos and Deimos. Both of these rocky moons resemble C type asteroids and may have originated elsewhere in the solar system before being permanently captured in orbit around the red planet. The inner moon, Phobos, orbits approximately 9377 kilometers from the center of Mars. The outer moon, Deimos, orbits more than 23,000 kilometers away from Mars. Our own Moon, orbits the Earth more than 384,000 kilometers away. It is interesting that Russia and China are currently planning a joint robotic mission to Phobos to be launched in 2009 to analyze-- and retrieve-- a sample of the material from the surface of Phobos for return to Earth.

The Martian Moon Phobos

The potato shaped Phobos has a maximum diameter of nearly 27 kilometers with surface area of approximately 6100 square kilometers and an estimated mass of more than 10 trillion tonnes. So at possibly 15 parts per million, Phobos could contain 150 million tonnes of platinum, enough to supply the Earth at current levels for about 500,000 years and at ten times current consumption for 50,000 years.

The Martian Moon Deimos

Deimos is the smaller outer moon of Mars. It has a maximum diameter of 15 kilometer and a total mass of approximately 1.5 trillion. So at 15 parts per million, Deimos could contain more than 20 million tonnes of platinum.

Even without platinum mining, the resources of the Martian moons would be extremely valuable for space exploration, space tourism and colonization and perhaps even for the extraterrestrial manufacturing and deployment of satellites in space. Because of the deleterious effects of cosmic and solar radiation, permanently manned facilities in orbit-- even within the Earth's magnetic field, are going to require at least hundreds to thousands of tonnes of shielding material. Phobos and Deimos with their low gravity wells have the potential to supply such shielding much more economically than such resources from the Earth or even the Moon-- if interplanetary lightsails are utilized to transport the material from the orbit of Mars. Approximately 40% of the chemical material of Phobos and Deimos is composed of oxygen, the principal oxidizer for rocket fuel and of course the essential element for breathing aboard space vehicles and orbiting space stations. Phobos and Deimos may also contain significant amounts of chemicals containing hydrogen, and essential rocket fuel and chemical component water (H2O) essential for human life and for growing food. Phobos and Deimos could also contain other valuable chemicals for growing food such as carbon and nitrogen. The metals and silicates from these Martian moons could also be used for manufacturing satellites for eventual deployment in Earth orbit.

Phobos has a tiny escape velocity of only 40 kilometers per hour (11.3 m/s). Deimos has an even tinier escape velocity of only 20 kilometers per hour. The Earth's moon, on the other hand, has an escape velocity of 2380 m/s. So transporting materials off the surfaces of these tiny Martian moons should be very inexpensive. However, Phobos and Deimos are still within the significant orbital influence of Mars which would require a delta v of 8.0 kilometers per second to transport material to low Earth orbit (LEO). So it would actually be cheaper to transport material from the lunar surface to Earth orbit than from the moons of Mars-- if chemical rockets were used.

However, there have been proposals to use lightsails (solar sails) for interplanetary travel. Unmanned lightsail space craft could transport hundreds or perhaps thousands of tonnes of freight practically anywhere within the inner part of the solar system from Mercury to Jupiter without any fuel cost. Lightsails simply use the reflected photons from the sun to provide acceleration for travel between the planets. While the acceleration of light sails is low compared to rockets, it is continuous. While a chemical rocket may fire its powerful engines for several minutes, a light sail can continue accelerating for hours, days, weeks, months and even years with zero cost of fuel. Such sails could be principally made of aluminum film as thin as 0.1 microns (one ten thousandth of a millimeter) and could be several kilometers in diameter while weighing less than 30 tonnes-- if constructed in space. Lightsails, therefore, could be the key towards giving humans affordable access to the vast material resources of the solar system.

Interplanetary light sail

So once material is transported out of the meager gravity well of a Martian moon, the delta v of getting the material out of Martian orbit would cost nothing since the cost of transporting material via light sail would only be determined by the capital cost of the sail plus the operational cost. In 1977, Eric Drexler determined that the cost of transporting material via lightsail could cost only 22 cents per kilogram; in 2009 dollars, that would be approximately 66 cents per kilogram ($66o per tonne, $660,000 per 1000 tonnes). However, if the source of material for light sail construction came from the low gravity wells of the Earth's moon or from the moons of Mars, then capital cost could potentially be even cheaper.

But even if the Earth were annually importing a million tonnes of material from the moons of Mars, and all of the platinum from this material was extracted, it would still only supply the Earth with about 15 tonnes of platinum annually (about 16% of current annual demand). So as far as platinum mining is concerned, it might be substantially more efficient to extract and process the platinum on site, on the surface of the Martian Moons.

If we assume that full fledged mining and processing facilities operated by a few companies on each Martian moon could conservatively process 10,000 tonnes of material daily on each moon, then about 110 tonnes of platinum (46% of annual demand) could be exported to Earth annually. Such large scale mining operations on the Martian Moons would probably require a significant human presence on the surface of Mars which would allow humans to operate such facilities mostly by remote control in the relatively healthier gravitational environment on the surface of Mars. It would also be much more convenient and cheaper for humans to access the Martian moons via rocket from the surface of Mars than from Earth.

Of course it might be possible to extract 10 million tonnes of platinum from Phobos and Deimos every year for the next 1000 years in order to supply all of Earth's current needs for platinum. This would still mean that only 0.1 per cent to 1 per cent of the total mass of the Martian Moons would be commercially exploited. But I consider Phobos and Deimos 'natural wonders' and would be strongly against over exploiting the resources of these Martian moons. The over mining of Phobos and Deimos might be somewhat alleviated by using lightsails to capture and import asteroids ( perhaps 500 to 5000 tonnes in mass) from the asteroid belt and transporting them safely into Mars orbit for processing.

But there are also many other large asteroids in the asteroid belt where platinum could probably be processed on site. And these large asteroids could help contribute to the platinum supplies needed for the Earth currently and in the future. There are nearly 30 large asteroids in the asteroid belt that are larger than 200 kilometers in diameter; and thre are more than 200 asteroids in the asteroid belt larger than 100 kilometers in diameter (all larger than Phobos and Deimos). These large asteroids would be lonely outpost that would probably require orbiting manned rotating facilities capable of producing at least some marginal but significant simulated gravity. Such outpost, however, would probably require thousands to millions of tonnes of radiation shielding that could be cheaply supplied by the host asteroids that they're mining.

The US currently has a 10 to 20 billion dollar a year civilian space program predominantly dedicated towards the 'exploration' of space and an even more expensive military space program. In my opinion, the new Obama administration needs to reprioritize NASA's goals away from space exploration in order to utilize their funds in a manner that would be more economically beneficial to the American people. Exploiting the natural resources of the Martian Moons would be a good start in that direction, in my opinion, which would probably require manned facilities on Phobos and Deimos, in Martian orbit, and on the surface of Mars.

Perhaps in the future when people are off duty after working all day or all week on the Martian surface or in orbit on one of the Martian moons, they could spend at least some of their free time-- exploring-- the exotic places where they're living and working!

New Papyrus 2009

References and Links

1. The Hydrogen Economy and Peak Platinum

2. Platinum (Wikipedia)

3. Highly Efficient Hydrogen Generation via Water Electrolysis Using Nanometal Electrodes

4. Asteroid Composition Table

5. Going (almost) all the way to Mars

6. AsterAnts: A Concept for Large-Scale Meteoroid Return and Processing

7. Why Mars?


9. World Book at NASA (Asteroids)

10. Mining the Sky: Untold Riches from the Asteroids, Comets, and Planets
John S. Lewis

11. Out of the Cradle: Exploring the Frontiers beyond Earth
Williams Hartmann, Ron Miller, and Pamela Lee

12. Lightsails

13. Solar Sailing- Eric Drexler

14. Starsailing: Solar Sails and Interstellar Travel
Louis Friedman

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