Stop The Hemorrhaging

Our economy is being destroyed by three separate but oil related factors.

  1. Our energy imports far exceed our exports of goods to other countries resulting in a huge trade deficit causing our currency value to plummet. In response to the plummeting value of the dollar, the fed can either raise interests rates, which will shore up the value of the dollar but cause our economy to go into a depression, or they can keep interest rates low, in which case our money becomes worthless and the cost of importing energy continues to go up.
  2. The cost of gasoline and diesel is rising in response to the low value of the dollar and increasing world demand, sapping what little life remains in our economy.
  3. The cost of the war in Iraq is draining our national treasury and enriching Halliburton.

The world can’t continue to depend upon reacting carbon with atmospheric oxygen for energy, at least not at a rate higher than that which other processes remove carbon dioxide from the atmosphere and and release free oxygen to the atmosphere.

In order to have the economic capacity to transition to other energy sources, our economy and the economies of the world need to be healthy.

To strengthen our economy we need to fix those things which ail it. Other countries have implemented a carbon tax to encourage alternatives and discourage consumption of hydrocarbons. I believe this is something we should consider doing but additionally but with several caveats. First, in order to prevent this tax from simply sucking more money from the economy, it should be revenue neutral. Second, I think in addition to a tax on hydrocarbons, there should be an additional importation tax on hydrocarbons such that to the degree which we still must rely on hydrocarbons, the oil companies are encourages to develop domestic resources.

I also believe that it is time to address our energy problems and our economic problems head on with massive federal programs similar to those invoked by Franklin D. Roosevelt that helped bring us out of first great depression. I’m not in favor of everything he did, but our energy and economic problems are not being solved by industries which have every economic incentive to maintain the status quo. We have homeless on the streets and people starving. We need to address the energy problem nationally and now.

I believe that we should launch a federal energy program that addresses our countries energy needs with the following elements:

Modernize the national power grid combining east and western grids and turning them into a super-grid combination super-conducting high-voltage DC power transmission system and liquid hydrogen distribution system. High voltage DC is superior to AC transmission because it eliminates radiative power loss. Superconductive transmission lines are superior because they eliminate resistive “copper” loss. Eliminating these sources of losses would be reduce electrical energy generation needs by approximately 15% nationwide while at the same time providing a national hydrogen distribution system.

Embark on a crash program of Apollo or Manhattan Project scale to develop controlled nuclear fusion. At this point the science needed to confine a plasma at the necessary temperatures and pressures for fusion to occur has been done. What remains now is some materials science research, determining how materials will stand up to intense neutron and ion bombardment that certain reactor components will be subject to, particularly a component known as a diverter which skims helium waste off of the plasma. ITER was to perform this function but it is twelve years before it will be online, we can not afford to wait this long to do the research necessary. ITER is also not the best design for this purpose. A spherical Tokamak would be a better choice because the confinement is approximately three times better in a spherical design. There are at least five other possible alternative fusion routes and we should be simultaneously exploring all of them as rapidly as possible.

Embark on a program to develop and build fast-flux breeder reactors that can make much more efficient use of uranium ore and burn transuranic actinides eliminating the long term nuclear waste instead of burying it. These would allow us to extract 60-70 times as much energy from the same amount of uranium or thorium ore, and at the same time eliminate the long term waste that must be kept isolated from the environment for 50,000 years producing waste that will be at the same level of radioactivity as it was when mined within only 300 years. In addition the volume of waste would be much less.

Embark on a program to gear up production of renewable energy sources that are already technically proven, primarily wind power which with the diversification that would be afforded by a national superconductive grid, could contribute a substantial portion of our energy needs. A superconductive super grid would allow excess energy to be made into hydrogen and stored. Emerging technologies, artificial photo-synthesis may make it possible to make hydrocarbons from excess electricity while simultaneously sequestering carbon dioxide from the atmosphere.

Embark in a huge research program that will create the necessary energy storage technologies to utilize intermittent power sources effectively and also to provide for our transportation needs. This will have the additional benefits of reversing the “brain drain” that presently is affecting our country by making jobs available for scientists here.

If we can solve our energy problems then we can also become an exporter of this new technology which will provide additional improvement in our trade deficit situation. We need to find the political will to tell the oil companies we will not continue with the status quo. They can either be part of the solution or they can wither and die.

Write your senators and representatives and tell them your vote is not for sale. If they want it they need to address these problems now.

The Cost Of Meat

I am not a vegetarian but I confess to feeling some serious guilt when I slice up a steak or even chomp down a hamburger.

Environmental costs of meat production are tremendous. Compared to soy protein, meat requires 6-17 times as much land, hydrocarbon fuels (oil), pesticides, and produces 6-17 times as much CO2 and water pollution.

You can only compare the environmental costs of meat production to soy or other plant based proteins when the land will support the production of plant based proteins. Humans are incapable of digesting cellulose. We can live on plants but we require protein and digestible carbohydrates.

While we can’t digest cellulose, cows and other grazing animals can. These animals then do provide human sustenance in regions of the world where the land will not grow suitable human food crops. We can hardly ask people living in these regions to stop eating meat because it’s unhealthy for the environment when they have no alternative.

Meat is also largely bad for our health, colon cancer, clogged arteries, stroke, heart attacks, meat contributes to these diseases. Some meats are much worse than others. How an animal is raised affects how healthy it is for you.

One thing that really puzzles me, given the much larger resource requirement for animal based proteins, why is it that fake meat patties, soy based, are more expensive than real ground up cow?

I’m trying to cut back but the expense of what should be cheaper alternatives makes that difficult.

Why Fusion?

I know a lot of people will ask, why a technological solution to problems technology caused? We can have a agrarian utopia with what nature providers, sunshine, wind, water, good earth.

I don’t wish to interfere with anyone who has that vision. They are welcome to purchase land, farm it in a sustainable manner, live with whatever level of technology they choose. I do believe the rest of us have an obligation to not pollute the planet so for those people who wish to live in that manner it is possible.

However, millions of people are living on land now that can’t support them, in Africa in particular. For those people to have a decent lifestyle they need to be part of a larger system involving trade, so that they can trade things they can make or do for food which they can not, on their land, produce in adequate quantities.

In order to bring those people out of poverty, the world economy needs to expand further; that can only happen with an expansion of the energy supply. If we expanded the energy supply by burning more hydrocarbons we’d hasten the demise of our ecosystem. We need a clean expandable energy source.

Expandable is a key word here, the density of solar power limits the degree to which it can be expanded. I have no doubt that solar and wind together could provide for our current energy consumptions with the appropriate infrastructure. However, by the time China and India scale their economies up to a level where their citizens can have a decent standard of living, and then also Africa, I do not feel as comfortable that these sources will scale adequately.

We are using water from the water table faster than it is replenished by nature. Soon, it will be necessary to desalinate and pump huge quantities of water in order to maintain the agriculture upon which we are dependent for food. Even with no economic expansion this will require large amounts of energy.

If not fusion, then I think we will be forced to rely on fission. Nuclear fission could be done cleanly and could provide power for millions of years through a combination of fast flux breeder reactors, on-site reprocessing, extraction of uranium from seawater, and the use of thorium fuel. With all the actinides re-used in fast-flux breeder reactors, there would be no actinide wastes, only fission products which decay to the same levels as they were when we mined the ore in 500 years, a much more short-term problem than the existing one-pass fuel cycle used here in the United States.

If we do not make either of these options happen, then I think we will doom many humans to poverty and starvation and I’d rather not see that happen, and of those two options fusion is infinitely cleaner and safer. There is zero possibility of a runaway reaction with fusion. There are no nuclear wastes produced as products of the reaction though with neutronic fuels there is some neutron activation of reactor structures so those will need to be dealt with when the reactor is dismantled. Even so that’s a trivial waste burden compared to fission reactors and most designs call for a lithium blanket to absorb most of the neutrons to breed tritium and shield reactor components simultaneously. Aneutronic fuels eliminate this issue entirely.

Fusion Energy Methods

I believe controlled fusion to be the Holy Grail of energy production for the human race given our current understanding of physics. I believe that when we understand physics better that may come with the ability to manipulate gravity, inertia, and time, and those abilities may render hydrogen fusion obsolete.

There are those who believe controlled hydrogen fusion is not possible or practical, I am absolutely not in that camp. I believe if we wanted to throw the resources at it, the type of resources we put towards the Manhattan project or Apollo, that we could have it online feeding power to our electricity grids within five years.

We are not throwing that kind of money at it. The US contribution to ITER, the first magnetic confinement confusion reactor that will operate at commercial power levels, is equal to what we spend on oil imports in two days. Two days worth of oil import money over twelve years for what could be the most important technological development in human history.

At this point, we know how to confine a plasma in a Tokamak good enough, we know the scaling laws, and we can engineer a power plant that will produce power. What we do not know is how some components will hold up under sustained neutron and ion bombardment. ITER will primarily be a materials research experiment to work out material issues and make any necessary refinements to components to operate in a sustained mode.

ITER was also to be the first reactor to use superconductive magnets for plasma confinement allowing longer operation. Current Tokamak’s are limited to one minute or so because they use copper coils which rapidly overheat. However, China built a reactor last year, EAST, using superconductive coils and so ITER will not be the first to do that.

ITER could be built more quickly if it were well funded. It is expected to be the last step between existing research reactors and a true power station reactor. So there is one path that if properly funded could bring us workable fusion soon.

ITER is a conventional Tokamak. There is an improvement on the standard Tokamak design called a Spherical Tokamak. In a normal Tokamak the plasma is donut shaped, short and wide. It was found that Tokamak designs where the plasma was less wide and taller, nearer to a sphere, performed much better, and in fact the idea plasma shape which turned out to be nearly spherical resulted in confinement that was more than three times better for a given magnetic field strength.

An UK based research group first designed a spherical research reactor called START, it out performed it’s design objective but was not designed for high power operation or break even. They then went on to design MAST, again not designed for break even but was designed for higher power operation so that plasma physics could be studied at higher power levels. MAST also outperformed design objectives. This same team then went on to design a commercial power reactor. As designed it would be less expensive to construct than a fission power plant of equal power. Given the track record of this group I find it odd that someone hasn’t offered to provide funding yet. So here is another route to fusion power that is sitting waiting for funding.

Then there is a reactor designed by Dr. Bussard, and I’m not aware of any name given to it yet so for now I’ll just refer to it as the Bussard reactor. Years ago there was a device invented by Dr. Farnsworth called the Farnsworth Fusor. This device used two concentric grids to accelerate deuterium and tritium atoms towards the center of a sphere where some collide and fuse. While useful as a neutron source, this device can not achieve high power levels because ion bombardment of the inner grid melts it.

The Bussard reactor is a very clever design that is based upon the fusor idea but sidesteps the problem of melting grids by creating virtual grids through magnetically steered electrons.

Many people who look at it believe it is an alternate approach to magnetic confinement fusion. It is not. The beauty of the Bussard reactor is that only electrons are magnetically confined. Electrons have a high charge to mass ratio compared to a proton or deuteron, and so a relatively weak magnetic field will suffice. The electrons are used to create a charge gradient that deuterons fall into and out of and oscillate through. This reactor uses electrostatic acceleration and confinement.

Prototypes were built, all performed as expected, scaling laws were understood, but funding ran out before a full scale version could be built. These reactors are super cheap to build compared to Tokamaks. This type of reactor is theoretically capable of reaching much higher collision energy levels making operations with aneutronic fuels possible. This in turn makes possible relatively compact designs because huge neutron shields would no longer be required.

The Levitated Dipole is a relative newcomer that is still highly experimental. It uses a levitated superconductive magnet to create a dipole field similar to the Earth’s. As with Dr. Bussards design, this method of confinement also may be capable of achieving energy levels that would allow the use of aneutronic fuels. This design hasn’t been tested sufficiently to really understand it’s potential yet.

Bogdan Magnich invented another approach referred to as Migma fusion. Two very low power particle accelerators aim two beams of deuterium ions at each other where they collide. The prototype found that the cross-section of the reaction was low and many ions missed each other and escaped. Maglich revised the design to trap deuterium ions in a magnetic trap that caused them to orbit in a circle in such a way that orbits intersected. Funding ran out and so far Dr. Magnich has not been able to find funding. This is yet another potential avenue towards controlled fusion as a power source and like the Bussard reactor and the Levitated Dipole reactor, this method has the potential of achieving the necessary energy levels for aneutronic fuels.

The above are pretty the limit of options that I believe have a short-term chance at being a practical source of electrical energy via fusion. But that’s five different avenues that I think are viable and four of them I believe could be brought online in a short time frame. The Levitated Dipole reactor is too new to really know it’s potential.

Then there is inertial confinement laser initiated fusion which while it keeps a lot of scientists employed around the NOVA laser system, a system of insanely powerful lasers that focus on a tiny pellet containing deuterium and compress it to one third it’s size and heat it to several hundred million degrees initiating fusion. While this approach works for one-shot and might be a way to trigger a nuclear fusion bomb without using a fission device, in terms of providing controlled nuclear fusion for energy generation I do not believe it has a chance in hell. It requires huge capacitor banks be charged which limits the cycle time and it is destructive.

Then there is are low power contenders, cold fusion, I am absolutely convinced it’s a real phenomena, I am absolutely convinced that it can’t be scaled up sufficiently to be a commercial power source for the grid even if reliability issues could be resolved. If reliability issues could be understood and resolved, it might be useful as a power source for small scale apparatus and possibly even vehicles provided it is both aneutronic and does not produce significant quantities of radioactive substances such as tritium.

The most familiar cold fusion experiment involves electrolytic cells in which deuterium ions are driven into a palladium electrode using electric forces. The theory has it that when the loading of deuterium into the metal is sufficient some form of fusion occurs. However, neutrons are not produced but excess heat and and helium are, also it seems some tritium and that may be problematic. This form has not been reproduced reliably but it has been reproduced. Some researchers have identified at least some of the variables so it can be made to happen more reliably but still not 100%.

However there are other cold fusion schemes that produce reactions, deuterium gas pressurized inside of a nickle tank produces neutrons. It is a very low power level howerver.

Bubble fusion, an off-shoot of sonoluminescence. Basically, when certain liquids are excited by ultrasonic sounds, little bubbles glowing blue are produced. This blue glow is caused by the bubbles being compressed and heated by the ultrasound acoustic energy. There is some evidence that fusion can be obtained in this manner. Not at high enough levels to be anything other than a laboratory curiosity, possibly a neutron source, but not a power source.

Crystal fusion.. I have to admit I like the name of this, but no it’s not a new age fusion reactor, it’s a device that uses special pyroelectric crystals which generate a high static charge when heated to produce a high voltage that accelerates deuterium atoms sufficiently to fuse. There is no reason to believe at this point that this would scale to commercial power levels.

This sums up the methods I am presently aware of. I’d welcome input from anybody that knows of others (preferably with pointers to online information).

Of these methods I believe the standard Tokamak, Spherical Tokamak, and the Bussard reactor are all immediately exploitable. On these reactors enough science has been done on the plasma physics and scaling laws to know how to build reactors that will produce power. Of these the Bussard reactor is the least developed but it is at least two orders of magnitude less expensive than the others so it is deserving of funding to produce a power producing prototype. The Spherical Tokamak has not had as much operational experience as standard Tokamaks but the experience with it has been very good. Because it is 3x as efficient at confining a plasma with a given magnetic field, it would be considerably less expensive than a standard Tokamak to build large enough to achieve a burning plasma. The Standard Tokamak is the most well researched, only some material questions remain and ITER will answer those.

Migma fusion is dirt cheap and for that reason alone it should be funded because we don’t have to gamble a lot to complete the research. A high school student with appropriate engineering knowledge could build one of these. This method is light and compact and could be a power source for ships, trains, planes, maybe even large trucks.

Levitated Dipole has the potential for being a useful power source but it is very immature at this time and not ready for prime time just yet, but if adequately funded that could change.

Peak Oil Debunked

I included a link to Peak Oil Debunked, not only because this person has taken a comprehensive look at the world energy situation and decided that not only is peak oil not immediately upon us but that civilization can continue even when that point is reached.

It is the demonstration of the latter that is of particular interest because many practical alternatives to oil as our primary energy source are pointed out and many of them are less obvious.

Here in the states, the ones we tend to hear about are only those that big corporations can make money on, and not so much the things we can do as individuals, or changes that can be “designed in” to new construction.

I think it’s a good resource so although on the surface it might seem to reinforce an oil economy, a good part of his argument is actually, “so what?”, with respect to peak oil, because here are all the alternatives…

Chinese Sustainable Energy Program

China, with it’s billion and a half citizens, faces a huge challenge. For them, it’s not just a matter of maintaining the status quo, it’s a matter of having a huge population desiring to enjoy a modern lifestyle.

They intend to attain that for their citizens by quadrupling the gross national product and doubling energy consumption by 2050 over what it was in 2000. They are presently depending upon coal to generate 75% of their electricity. Their target is to reduce that to 38% by 2050. Presently electricity demand is increasing 15% per year and coal fired plants are the fastest way for them to meet that demand. Chana is installing more than one 1000 MW coal fired plant per week at present.

The pollution generated takes a huge toll on not only the health of Chinese citizens, but also on food production. The haze generated by burning all of that coal reduces net sunlight at ground level by more than 1%, with an attendant reduction in food crops. Presently, there is more than 250 GW of coal fired generating capacity under construction or in the pipeline. Already, over 40% of China’s rail capacity is dedicated to hauling coal, pollution aside this trend can not continue indefinitely.

China is planning on transitioning towards renewable sources, small scale hydro, biomass, wind, and solar among them. China also tends to make use of nuclear fission and in addition is aggressively pursuing a fusion research path aimed at bringing fusion online commercially.

To gain an understanding of just how aggressively the Chinese are pursing fusion power, consider this. The rest of the world is contributing to the twelve year construction of what was to be the worlds first superconducting tokamak fusion reactor, ITER, to allow sustained operating at commercial power levels so material issues such as how the diverter would function long term and engineering issues like heat load and neutron embriddlement could be worked out. The US contribution to this project over a 12-year period amounts to less than what we spend on imported oil in two days.

By contrast, the Chinese started construction of a superconducting fusion test reactor in February of 2006, it say first plasma in September of 2006. I’m going to lay odds that they will have fusion power online commercially before ITER is fully constructed.

China intends to build an additional 30 nuclear fission reactors for power production over the next fifteen years and by 2050, China intends to have a total of around 150GW of nuclear capacity online. This equates to about 150 nuclear fission plants if a gigawatt design is used, presently domestic plants are of a 300 MW and 600 MW size.

The Chinese are also having great success with wind power. While electricity produced by coal fired plants is averaging around 8¢/KWh, electricity produced by wind is averaging about 4.5¢/KWh. As one might expect, that is making wind power look like a very attractive investment, however, it can not be scaled up presently as fast as coal can and consequently coal still leads new power production. I suspect though that the economics of wind power will drive a rapid acceleration in the rate of wind power production.

China is also exploring advanced high temperature nuclear fission reactor technology. Conventional boiling water reactors or pressurized steam reactors operate at low temperatures with resulting poor thermal conversion efficiency. However, South Africa has produced and is operating gas cooled pebble bed reactors which can operate at far higher temperatures with an attendant improvement in efficiency.

China has demonstrated the inherent safety of a 10 MW pebble bed reactors by shutting off cooling while the reactor was operating at full power and demonstrating it’s ability withstand that without damage or radiation release. Pebble bed reactors use fuel pellets about the size of billiard balls that contain fuel inside of a graphite ball, and in some designs that is in an outer casing of silicon carbide. In my opinion the latter is a much better design because silicon carbide is not reactive with oxygen so even if the containment vessel cracks a silicon carbide encased fuel pellet will not allow radioactive materials to escape where a graphite pellet could potentially burn in that situation.

Pebble bed reactors are safe and thermally efficient, however, they are not efficient in their overall use of fuel because their operation is inherently one-pass meaning less than 1% of the uranium fuels potential can be extracted. The spent fuel is difficult to extract from used pebbles and so at present no reprocessing technology exists and the fuel can not be reprocessed.

Those are some of the things happening in China. I think it’s worth while viewing how other countries are addressing their energy needs and environmental concerns. For the time being China’s dependence upon coal is catastrophic for the environment but they are working on transitioning from coal which I see as a positive step.

Rig Zone

Even though in my opinion burning hydrocarbons for energy is the antithesis of a sustainable economy, I’ve added to the sidebar so those of you who wish to keep track of what the oil companies are doing have that resource readily available.

If you take a look at it on a daily basis, you won’t miss on the oil field discoveries. If you dig around a bit, the field development tab is a good place to look, you can look at the specifics, how much oil they find, how development is going on a particular field, the estimated production life of that field, etc.

Peak Oil

In spite of everything I’ve presented here there are people who still want to buy into the peak oil scam. I’m not sure how much I should try to convince people otherwise because while there isn’t a peak oil situation immediately looming, at least not in the sense that we’ve used up half of all the worlds oil reserves, there is the problem of damage to our environment, and that is real and threatening and the right reason for transitioning to alternatives to oil.

I’m sure that James Howard Kunstler is a far more persuasive author than I am, and he’s also motivated to sell books. So what chance do I have of competing?

Those of you who really want to know the truth, it’s out there if you dig for it. One place I like to look is It is geared towards the oil industry and consequently not high in entertainment value like Kunstler’s book, however, it contains real data, the new oil field discoveries, the technological developments, the economics involved. There are other sites like it but that one makes everything available to anyone who cares to go and take a look.

On the other hand, if you just want to be entertained, read Kunstler’s book. Really, I’m not sure it’s a bad thing for the public to believe a peak oil crises is upon us, because if that actually provides the motivation to get us to move onto something environmentally less damaging then it’s not a bad thing.

My only gripe with the peak oil scam, besides the fact that it is a scam, is that by creating a perceived shortage it’s driving the price of oil up and sucking money out of the economy that could be used to invest in alternatives. It’s also causing major problems for many people economically forcing people to choose between heating and eating while the oil companies rake in 35 billion a quarter in profits. And it’s causing many Americans to look the other way while we conduct a war in the middle east because they believe it’s securing oil. In reality, it’s cut the production in Iraq considerably driving the cost of oil up which of coarse is what the multinationals had intended in the first place.

All of this isn’t to say that cheap oil is not getting scarce. There is plenty of oil left but it’s not the low sulfur light crude under so much pressure that all you have to do is poke a hole in the ground and it comes gushing out. There is plenty of deep oil, the kind you have to drill down 20,000+ feet and through granite or basaltic capstone to get to. There is plenty of oil shale and tar sands, which yield thick bitumen that has to be cracked into lighter molecules in order to be commercially useful and that increases refinery costs. There is about as much heavy oil in California as there is Venezuela. There is much oil off the Gulf of Mexico yet to be tapped but much of it is in deep water and requires deep drilling to get to. There are regions off the Pacific coast believed to have oil but they haven’t been allowed to even be explored let alone tapped.

I’d much rather see us move to clean renewable resources than tap all of these and spew more filth into the atmosphere and environment in general. I’d rather see it happen though because it’s the right thing to do for our planet and not because oil companies thought they could boost their profits by creating a perceived shortage.

Nuclear Fuel Shortage?

This article concerning a nuclear fuel shortage, on MIT’s website, leaves me shaking my head and wonder what they up to. There has to be an agenda behind this besides a genuine concern over having enough fuel for reactors because if we really had a fuel shortage we wouldn’t be creating a national waste repository that is intended to store nuclear waste for 20,000 years.

Some background is necessary regarding the entire nuclear fuel cycle. We mine natural uranium ore, the uranium once extracted from that ore contains proximately .72% U-235, and 99.27% U-238, and .0055% U-234.

In a uranium fueled nuclear fission reactor, the isotope U-235 is the fuel because it can be caused to fission, that is break into lighter elements, by absorbing a slow (thermal) neutron, and in turn also give off neutrons when that happens, which are then absorbed by another U-235 atom, continuing the chain. The resulting daughter elements are slightly lighter than the original uranium element and that mass difference is converted into energy.

U-238 isn’t completely inert however. It absorbs neutrons becoming U-239, decays to Np-239 through beta emission (emits an electron, one of the neutrons becomes a proton), and then Np-239 decays into Pu-239, again through beta decay. Pu-239, like U-235 is fissionable with thermal neutrons.

Thus in a reactor fueled with U-235 and U-238, a percentage of the U-238 atoms will absorb neutrons and become Pu-239 adding to the fissionable fuel inventory in the reactor.

However, notice that U-238 does not emit neutrons during it’s conversion to Pu-239. A light-water moderated reactor can not sustain a nuclear chain reaction with a natural isotopic mix. It is possible to sustain a nuclear fission chain reaction using natural uranium if graphite or heavy water is used as a moderator. Heavy water is expensive in the quantities required and graphite is a fire hazard as was demonstrated in Chernobyl.

To get around this problem uranium is enriched, isotopes are separated using gas diffusion, centrifugal, or laser isotopic enrichment methods so that fuel containing 2.5%-5% U-235 and 95-97.5% U-238 results.

When natural uranium is enriched, typically 15% of the natural uranium becomes enriched uranium at 3.5% U-235, and 85% becomes deplented uranium with .3% U-235. So only 29.2% of the U-235 present in the original ore ever gets into the reactor and about 17% of the U-238. More than 80% of the energy potential of the ore has been eliminated before it ever makes it into the reactor.

During the reactors operation, approximately 1% of the U-238 is turned into Pu-239 and a percentage of that is then fissioned along with U-235 fuel. But at some point the ratio of fissionable isotopes drops too far and waste products that absorb neutrons but do not fission and supply neutrons increases to the point where a chain reaction can no longer be sustained and the reactor must be refueled.

At that point when the spent fuel is removed from the reactor and placed in waste ponds, only 4-5% of the U-238 present in the original fuel (1% or so of what was in the original ore) was used and much of the Pu-239 bred from that is still unused as well as a percentage of the original U-235. Between than .75% and 1% of the natural uranium’s energy potential has been utilized in a one-pass fuel cycle.

MIT is saying we have a fuel shortage because we are presently mining uranium at a rate of only about 65% of the rate that we’re using it in reactors. In the United States, reactors are only using it in a 1-pass fuel cycle and thus more than 99% of the energy potential of that fuel is being wasted.

In addition to that we have huge stockpiles of Pu-239 that have accumulated as part of the weapons programs in the United States and Russia and this also could be used to fuel reactors. It is more problematic however because it is relatively easy to build a bomb from Pu-239, but not from reactor grade uranium which is only enriched to a maximum of around 5% and more typically 2.5-3.5%.

The problem that shuts down the reaction isn’t just a lack of fissionable U-235 and Pu-239, it is the build-up of other actinides, elements heavier than uranium, which absorb thermal neutrons but do not fission and provide additional neutrons as well as some fission products that are neutron absorbers which poison the reaction by absorbing too many neutrons. Fission products also create mechanical problems.

If we reprocess the spent fuel, remove the U-235 and Pu-239, and re-use those in MOX fuel (mixed metal oxides, U-235 and Pu-239), and do this to the greatest extend that we can, we can extract around 2% of the uraniums fuel potential.

Just moving from a single pass to a multi-pass fuel cycle would reduce the amount of uranium that we would need to mine to less than that which is currently being mined. There really isn’t a shortage of uranium, it’s just less expensive to mine fresh ore than to reprocess waste.

We should reprocess, because by doing so not only do we reduce the amount of uranium that needs to be mined, but we reduce the long-lived radioactive wastes by a similar amount.

However, there is a way that we can extract 60-70% of the uraniums fuel potential (with current isotopic separation efficiency) and eliminate most of the long-lived radioactive waste.

In the spent fuel there are two radioactive components. Actinides which includes uranium and all elements that are heavier, and fission products, the daughter products of the fission products. The fission products are highly unstable and decade to stable isotopes in a relatively short time frame. By the time 300 years have passed, they will have decayed to the point where there radioactivity is no higher than the natural ore that was originally mined and are considered safe for disposal at that point.

It is the actinides that are problematic because they have much longer half-lives and it will require in excess of 20,000 years for them to decay to the point where radioactivity is no greater than the original ore.

Of all the actinides produced, only the isotopes U-235 (present in the original uranium fuel), U-233 (bred from thorium, and Pu-239 and Pu-241 are fissionable with thermal neutrons. But all of the actinides are fissionable with fast neutrons. Burning these requires the use of fast-flux nuclear reactors. Early fast-flux reactors had some inherent safety issues because reaction rates could vary rapidly.

However, generation IV reactors have been developed which have inherent stability features. For example, fuel designs that have negative temperature – reactivity coefficients such that as the temperature increases the reaction rate automatically decreases. There are numerous schemes for accomplishing this.

In general fast-flux reactors use either a liquid metal (typically sodium or lead), a liquid salt, or a gas coolant operating at greater temperatures than a boiling water or pressurized water reactor would operate at. This higher temperature translates into higher efficiency. Also, the liquid metal cooled reactors operate at close to atmospheric pressure so there are less plumbing problems.

By using these reactors, 60-70% of the energy content of the uranium ore can be extracted. This can be improved further as separation efficiency improves. Right now however, we have an excess of weapons plutonium stockpiled that can be blended with natural uranium rather than enriching it, and that is providing for a portion of our fuel needs and is the reason we do not have to mine more.

The cost of uranium is a trivial portion of the total cost of producing electricity. If it were to increase by 100x, it would still only account for approximately .7¢/KWh and a 100x cost increase would increase the supply tremendously.

A uranium shortage doesn’t exist and won’t limit nuclear power production. Intelligent use of uranium could reduce the fuel consumption to less than 2% of that which is presently required to generate a given amount of electricity. Thorium can be used as a fuel and there is 3x as much thorium in the Earth’s crust as there is uranium, and what’s more uranium produces more long-lived actinides than does thorium for the amount of energy produced.

What is the motivation behind MIT’s announcement of an impending uranium shortage?

Heat Pump Dryers

The Japanese have had microwave clothes dryers for some time. These use microwaves to heat the wet clothes rather than hot air and by doing so they save approximately 35% in energy consumption. They switch to resistive heating for about the last 10% of the cycle to prevent problems with metal objects. For reasons I am not familiar with these are not available in the United States.

Heat pump dryers are now available in the United States, and these save approximately 65% of the energy consumed by an ordinary dryer. Dryers generally represent around 6% of a households energy consumption, and if you have teenage kids even more. In addition to directly consuming 6% of a households energy budget, dryers also contribute to energy required for heating and/or air conditioning because the air they exhaust to the outside hot came from the inside, and that air will be replaced by cold or hot air from the outside requiring additional energy for heating or cooling the house.

Heat pump dryers cost about $300 more than a conventional resistive heating dryer. Over a ten year lifespan, they will save approximately $1000 in electricity costs assuming the average cost of 8¢/KWh and average household laundry. The savings will be even greater where the rates are higher or if your household has a higher than average amount of laundry. This is before you factor in heating and air conditioning savings which are even greater.

A heat pump dryer is also more convenient to install, requiring only a drain like a washer and no external vent. In addition a heat pump dryer requires only a standard 120 volt outlet, not the larger 240 volt 30 or 40 amp circuit of a resistive heating dryer.

Instead of heating air, blowing it over clothes, and then exhausting the hot air outdoors and taking fresh air from indoors, a heat pump dryer heats air, passes it over clothes, dehumidifies the air, and passes it over clothes again and again. No air is exhausted outdoors, and liquid water from the dehumidified air is simply drained. Heat energy is not wasted.

Not including the savings in heating and cooling, if everyone switched to heat pump clothes dryers it would save 445 billion KWh of electricity every year, 35 billion dollars in electricity costs each year nation wide. Because our trade deficit, and economic woes, are in large part the result of the energy we import, this would be a very good thing for our domestic economy. Surplus electricity could be used by electric vehicles, or we could burn less natural gas for power generation and instead liquify it and use it to power our vehicles instead of imported oil.

It would reduce the average load on the power grid by 50 megawatts, about 1/10th the output of a medium sized nuclear reactor, but it would reduce the peak load by more than this because most people don’t do clothes at 4AM.

Anything we can do to save energy consumption will allow a larger portion of our energy needs to be satisfied by renewable and environmentally benign sources and less carbon dioxide will be generated as a result.

Don’t get me wrong, I actually like warm weather. It’s the species dying off, cities underwater, desertification of farmland and forest, things that really bothers me. Unfortunately they seem to be an intrinsic part of global warming. A great deal of global warming would be happening without our contribution. We should not accelerate or intensify it further by altering our atmosphere.

Even better than a dryer when weather permits is a clothes line. 100% renewable (solar) powered, no electricity consumption.

Heat Pump dryers are available in Japan and Europe from multiple vendors but like microwave dryers they are not widely available in the United States. One company that does produce a number of heat-pump consumer appliances is Nyle Special Products, and I’ve included a link on the side bar. If anyone knows of other suppliers that make household heat pump dryers available in the United States, please contact me and I will add them.