Various approaches to the building of the Liquid Fluoride Thorium Reactors (LFTR).
—The Continuing Discussion of the Developing the Physical Economy of Humanity's Thorium Future—
On the central clearinghouse for all things LFTR, energyfromthorium.com we've had wide ranging discussions on every single conceivable aspects of LFTR and what it means:
1. How to build them?
2. Safety issues
3. Proliferation issues
4. Financing LFTR
5. Fueling LFTR
6. Deploying LFTR
7. LFTR applications
8. LFTR as a "Thorium Bullet" to solve 100% of our energy needs and the launching of the Thorium Century.
And that, folks, is a small list.
Point 2 above is what I want to focus here on.
The small scale size of the LFTR…maybe as little as 1/3 the size of an equivalent Light Water Reactor for the same MW output...and the ability to build LFTRs from as small as 5MWs up to 1.8 GWs (or bigger) gives LFTR siting a far more flexible deployable possibilities than any other source of energy except, perhaps, diesel electric generators used throughout the would for smaller grids and remote applications.
But the smaller intermediate units, from the 100 to 500 MWs range, used as a replacement for gas fired peaker units (site restricted for environmental reasons and access to natural gas lines) and baseload replacement of coal, allow a more creative approach to application of this, real Generation IV fission energy.
My own contribution to this in the past few years was the "Missile Silo" paradigm. A subsurface structure, with a removable, concrete reinforced 'lid' on top, making for barely any above ground profile.
Excavations can be made using standard industrial reinforced concrete for the floor and sides, much of that modularly cast above ground and installed below ground. The LFTR modules, turbine generator train, etc can be brought in and lowered into place and assembled. Only the control room and, the air/water coolers would be above ground (air cooled condensers or low profile cooling towers/once through cooling if located near surface water supplies).
LFTRs are small because they are operate at normal atmospheric pressure and don't require the huge containment domes and heavy piping you see around nuclear plants today.
But there is another, more fascinating, and perhaps much cheaper way to deal with LFTR sitings. Build them on barges in shipyards and ship them whole to any site with navigable sitings…like existing coal plants, for example, many that have river or canal access.
The Russians are in the process now of building floating nuclear power plants of the pressurized water reactor style used on Russian maritime vessels and submarines. They are marketing them as being deliverable almost anywhere in the world. The LFTR can follow this paradigm but the floating LFTR is not what I'm proposing.
Secondly, Northrop Grumman Shipbuilding and nuclear giant Areva just started construction of their nuclear components factory at Grumman's Newport News Shipyard: to use the facilities, cranes and drydock to help build, assemble and ship their components around the globe.
The barge the LFTR would be sitting on would not be a temporary structure designed to either transport the LFTR or as a permanent floating lodge for the power plant.
Here is a generalized outline of how the construction/assembly/shipping/siting would work:
1. Factories and machine shops in the shipyard would upgraded, where needed, to nuclear specifications.
2. These factories and shop would forge, shape, assemble and finish components for the LFTR.
3. Additionally components manufactured elsewhere would be laid out in the shipyard.
4. A barge would be built big enough to transport, either for ocean going or inner-coastal transport, that would be towed to the siting.
5. The LFTR barge would be assembled in the dry dock using existing facilities at the shop yard.
6. As the barge is built from the bottom of the drydock up, the main decking would be jacked up over the keel of the barge and sub-assembly of the LFTR and it's main components would be assembled: reactor core, associated piping, heat exchangers, turbine, generator, lube oil and associated balance of plant equipment.
7. The barge would be built for permanent dry stationing at a prepared site.
8. The site would be excavated and prepared with a temporary caisson off the main navigable waterway. The caisson is like a dam used to block water from following into the dry dock.
9. After the LFTR barge is assembled and towed to the site the caisson would be put back in place and the barge/site temporary drydock would be drained.
10. The LFTR barge would settle on prepared pre-stressed concrete blocks.
11. The LFTR barge itself would be of steel and concreted design and completely self contained as a nuclear power plant.
12. 1 large LFTR could be transported and sited this way or numerous smaller 100 to 500MW LFTRs on one barge as needed-->All "Factory Assembled".
13. The areas around the barge and supports could then be filled in with spoil or clay or concrete depending on regulations.
14. Hooking up the LFTR to the site balance of plant would commence (station power, grid access, control room, etc).
Charles Barton and others at energyfromthorium.com/forum are noted for advocating that the smaller LFTRs be constructed in-lieu of a larger one because it could be completed basically in a small series of modules and easily trucked and then assembled on site. This would be next to impossible for the larger 1GW-plus reactors as even the smaller-per-MW LFTR of this size is way to big. The advantage of course of the smaller ones is that they could, in theory, be composed of all-assembly line built components mass produced for low price and high volume.
The shipyard metaphor, described above, combines both this concept of factory production with the "line production" of large air craft and ships using existing facilities that give LFTR manufacturers the flexibility of designing any number of sized LFTRs, from the smallest 5 MW (or smaller) which could be shipped on an air plane to multi-module larger sizes of the plus-GW capacity…all factor produced and assembled, ship whole and sited in one fell swoop.
Saturday, July 25, 2009
Wednesday, June 17, 2009
Large vs. Small LFTR Reactors
Large vs. Small Nuclear Reactors
A comradely debate and discussion has been going on for a number of years over on the energyfromthorium.com/forum web site, the pre-eminent web site for all things concerning the Liquid Fluoride Thorium Reactor.
This contribution to that discussion will focus on the LFTR but a few other items of important to note.
This week, Babcock and Wilcox announced their new mPower reactor. It's a light water, pressurized water reactor like almost all currently running reactors but they are very, very small: 125MW modularly build, sited underground, reactors. B&W is suggesting that costs will run between $4,000 and $5,000 a KW installed, or, about $1 billion and change for one of these modules.
B&W joins a host of other companies and proposals for small reactors that include:
Hyperion Power Generations [http://www.hyperionpowergeneration.com/] Hyperion Power Module, designed for process heat (approx 70MW thermal) and 30 MWs of electricity if hooked up to turbine generator stet.
Toshiba's 4S (Super Safe, Small and Simple) reactor. [http://www.roe.com/about_techGalena.htm] This power plant is designed to provide 10 Megawatts of electrical power.
Even the Russians have developed one off of their advanced lead-cooled submarine reactors: The The SVBR-100 reactor. [http://sovietologist.blogspot.com/2009/06/svbr-russia-makes-it-modular.html]
Lastly, but certainly not least, Rod Adams, from Adam's Atomic Engines, also has a very small reactor design using a brayton cycle gas turbine with nitrogen as it's cooling source for the reactor and the propulsion for the turbine.
Modular Construction
All these reactors offer modular construction, transportability of those modules or even whole units to a siting, simplified and passive intrinsically safe designs, and affordability, items that for the most part the larger 1000+ reactors currently being deployed cannot, for the most past, offer.
Before getting into the question of 'large' vs. 'small' reactors, we need to parse out what the various reactors can be used for based on their 'product' and use and how the LFTR fits into all this.
Scalability/Uses
The LFTR is unique from all of the above because it is amazingly scalable...there is no real downward or upward limit to the size or use a LFTR can be employed in. Say, from a small LFTR 'battery' of 20 MWs to a large, base load plant offering 1800 MWs gross base-load power to the grid.
It is my contention that there will be a 'market' for all these sizes. We should first review what these markets are.
On the smaller end, the LFTR, as a high temperature reactor, can provide process heat. A small chemical plant, requiring thousands of tons of steam an hour, can use a LFTR to provide this heat and, to electrically power the plant. A slightly larger version may be able to provide power and vast qualities of heat to an oil refinery or a tar-sands operation thus providing carbon-free process heat to what otherwise would be a huge carbon-spewing operation.
These smaller LFTRs, from 20 to 200 MWs could provide, also, site specific load balancing for a grid that has a lot of load in place but generation many hundreds of miles away. Using a 200 MW LFTR to 'anchor' the grid would be very helpful to any utility. Additionally these smaller LFTRs could be plopped down in various transmission substations to provide quick, peaking power or variable load changing that responds to frequency changes throughout the day.
Additionally, along the process heat scenarios, these small and, larger LFTRs can be used to cheaply crack sea water into various products including and most desirably, hundred of thousands of cubic meters of fresh, potable water for drinking and agriculture, thus allowing a huge increase in agricultural output in drier climates, like California, Egypt or Tunisia. Thus electrical generation would be, or could be, the co-generation product of such plants. Additionally, another such product from process heat could be the cracking of hydrogen from water using high-temperature electrolysis, thus providing yet another alternative fuel for automotive transport.
Larger LFTR units could be would be used for base-load generation. Phasing out gas and coal plants with big 1000+ MW units.
There are many uses for all sizes of LFTRs that are all designed basically the same. Energyfromthorium.com has papers and discussion on how all this works, so I won't go into basic LFTR technology here.
One thing that is important for this discussion to note, however, is that LFTRs, from the get go, are cheaper to produce, having a much higher power density than any currently running or under-construction Generation II or III Light Water Reactors. From the reactor core itself to the turbine, size is about 1/2 to 2/3 smaller, thus allowing for a cheaper, and therefore far more efficient, product based on size/cost per MW output. We are looking at, generally a similar ratio in cost reduction.
So...to the meat of the issue
It is my contention, or thesis, that there is a use for both the smaller scale, sub-300 MW LFTR units AND the larger, up though 1800MW LFTRs as well.
The argument is poised this way: is it cheaper (safer, easier, efficient, etc etc) to build, for example, 15 100 MW LFTRs vs one 1500 MW LFTR to achieve a 1500 MW requirement for a single location? This is the heart of the debate.
Charles Barton over at nucleargreen.blogspot.com and a keen observer of nuclear and 'renewable' energy costs. Many nuclear bloggers have as well. I'm not an economist, financial expert or engineer. My experience is simply one of a interested observer, and commentator, on energy issues. Charles is an advocate of the LFTR deployment being one of small reactors. He has many blog posts on this question and I urge all left-atomics readers to go to his site and look for these posts.
Advantages of Smaller LFTRs...
So...what ARE the advantages of a small, sub-300 MW, or sub-100 MW LFTR? Because the overall size of a LFTR is at least 1/2 the size of the equivalent LWR to start with, and these smaller lifters are 2/3 to 1/10 the out put, small LFTRs may able to be transported, in total, on three tractor-trailers or rail cars (reactor core/housing, turbine, generator). Given that construction costs of large, LWR amount to almost half the costs of a large reactor today, this is a tremendous savings.
Additionally, almost the entire module assemblies may well be assembled in a factory, on a production line similar to that of the building of passenger and cargo aircraft today. Production costs for smaller, but quantitatively greater, components ARE the cheaper form of production based on economy of scale.
The reality, however, is that even for larger reactors of the LFTR variety, almost all their components are also factor built, just like in today's' fleet of reactors. There is something of a 'production myth' that these large reactors are somehow built more primitively. Almost every single component in a modern nuclear reactors is built 'on a line'. But even small pumps, motor, controls, etc are built 'by hand', albeit in a factory. A 100 HP pump is hand assembled for the most part, albeit the parts that compose the whole pump are more likely to be manufactured on a true assembly line process.
I suspect as we parse out the true production costs for larger and small components, even the smaller ones for the small LFTRs that the costs are not that different from the larger units.
The advantage for the smaller LFTR is that many more modules for different aspects of the plant can be cobbled together in a factory as opposed to hand assembled on site. Generally, the rule holds that a system that comes 'ready-to-install' it is cheaper than one assembled by hand on site. A CO2 fire suppression system is an example of this. While the pipe runs to each piece of electrical equipment has to be hand run, the CO2 discharge assembly, composed of dozens of small, say 1" diameter, pipe runs, regulators, pilot and stop valves, on unit that is, say, 10 feet by 10 feet, can easily be built in a factory and shipped to the site. But in a bigger plant, where you need pipe discharge valves and runs that use use, say, 2 and 3" diameter pipe and valves, and is 20 feet by 15 feet, then assembly on site may have to occur. Thus an increase in expense.
But If...
But if...and this is the big "IF", this bigger assembly which can service a 1000 MW plant is more expensive per unit, say by a factor of 3 (for the labor it takes to assemble it on site as opposed to a factory, and the large individual sub-components cost more as well), but you need 10 of the smaller cheaper assemblies for the 10 separate LFTR units, then those cost savings for the 10 smaller units disappear and are actually more expensive by a factor of 3.
So, what all of us need to do, and it would help if actual operations engineers, construction engineers, and manufacturing engineers chimed in here, is actually parse out the true costs of a complete, say, 100MW LFTR and that of a 1800MW LFTR. I argue that it will be *impossible* to determine until all sized units are built in mockups to scale, during the R&D that precedes actual deployment. We simply will not know.
Some more things to think about. A big expense for any reactor and turbine generator set are controls. This including things like monitoring radiation, temperatures throughout the reactor-to-heat exchanger loops to the turbine and, of course, volts/amps/watts on the generator. A generator, regardless of the size, has a voltage relay device that reads the system voltage and the voltage of the generator. A set of leads from the high and low side of the transformer banks "potential transformers" (PTs) runs back to a relay and monitor in the plant's control room. There are *hundreds* of these sorts of systems on any modern power plant, regardless if they are geothermal, conventional steam plants or hydro units.
The PTs generally are all the same size and installation uses the same methods. Their testing, 'stressing' and maintenance are all the same based on conditions at the plant. So, regardless of the size of the LFTR, they will all get the same sort of PTs and all the costs associated with them. So, for 1500 MW plant, the costs for 15 100 MW LFTRs for the PT sets required are *likely* to be 15 times more expensive than for the 1500 MW unit (to be fair, there may be a larger redundancy for the larger units as they often have more than one transformer bank). But even if divided by 2, the costs, or "economy of scale", is now reversed and favor the single larger 1500 MW unit.
And this, fellow nukes, is my point. All these factors have to be taken into account when supplying what the customer wants in terms of gross MWs installed in a single location.
To be fair, this is VERY, very simplified presentation of counter-positions. But this does need to be seriously parsed out, eventually.
I believe the real advantage of the smaller units will be it's flexibility in installations, where they can be located, how, etc. Many times utilities want the bigger units because the are compelled by many reasons to group their "MWs together" in one big unit. The smaller LFTR modules can be "distributed" for, in some/many cases, a more reliable grid. Thus the same 1500 MWs the big public utility may want can now be distributed over a greater, and therefore more reliable area. Because the price difference and environmental impact for doing this with conventional fossil plants was prohibitive, you did not see this occur. Thus the LFTR gives advantage because if it's "infinite scalability" to distribute it's power production.
Secondly, and more importantly, while I will continue to put an "equal sign" between the big and small versions of the LFTRs that will be deployed in the future, for many, perhaps most, parts of the world, the smaller LFTR versions will be highly desirable. Many countries have electric grids that have, because of the legacy of colonialism and imperialism, war and revolution, dilapidated, incomplete or basically retarded development and mass under or non-electrified sections of their countries. This is one of the reasons why India is still interested in nuclear energy in *under* 700 MW units.
A grid that is relying on 200 MWs of diesel powered in 10 locations and subject to blackouts, fuel shortages, can add, for example, as part of a rural and small town electrification program, a set of, say, 3 100 MW LFTRs to boost over all capacity to 500 MWs while load increases from 200 to, say, 300 over a year or two. Multiple non-joined grids could be developed this way and then joined as transmission finally ties the country or region together. Smaller, 50 MW LFTRs can be installed incrementally. Eventually you'd have a larger, regional grid composed of about a dozen or more variable sized LFTRs. As the economy improves because of the addition to the *physical* economy of the nation gets stronger, larger LFTR units could be installed in more centralized locations with the smaller ones previously installed used to balance frequency/voltage and provide peaking power.
A comradely debate and discussion has been going on for a number of years over on the energyfromthorium.com/forum web site, the pre-eminent web site for all things concerning the Liquid Fluoride Thorium Reactor.
This contribution to that discussion will focus on the LFTR but a few other items of important to note.
This week, Babcock and Wilcox announced their new mPower reactor. It's a light water, pressurized water reactor like almost all currently running reactors but they are very, very small: 125MW modularly build, sited underground, reactors. B&W is suggesting that costs will run between $4,000 and $5,000 a KW installed, or, about $1 billion and change for one of these modules.
B&W joins a host of other companies and proposals for small reactors that include:
Hyperion Power Generations [http://www.hyperionpowergeneration.com/] Hyperion Power Module, designed for process heat (approx 70MW thermal) and 30 MWs of electricity if hooked up to turbine generator stet.
Toshiba's 4S (Super Safe, Small and Simple) reactor. [http://www.roe.com/about_techGalena.htm] This power plant is designed to provide 10 Megawatts of electrical power.
Even the Russians have developed one off of their advanced lead-cooled submarine reactors: The The SVBR-100 reactor. [http://sovietologist.blogspot.com/2009/06/svbr-russia-makes-it-modular.html]
Lastly, but certainly not least, Rod Adams, from Adam's Atomic Engines, also has a very small reactor design using a brayton cycle gas turbine with nitrogen as it's cooling source for the reactor and the propulsion for the turbine.
Modular Construction
All these reactors offer modular construction, transportability of those modules or even whole units to a siting, simplified and passive intrinsically safe designs, and affordability, items that for the most part the larger 1000+ reactors currently being deployed cannot, for the most past, offer.
Before getting into the question of 'large' vs. 'small' reactors, we need to parse out what the various reactors can be used for based on their 'product' and use and how the LFTR fits into all this.
Scalability/Uses
The LFTR is unique from all of the above because it is amazingly scalable...there is no real downward or upward limit to the size or use a LFTR can be employed in. Say, from a small LFTR 'battery' of 20 MWs to a large, base load plant offering 1800 MWs gross base-load power to the grid.
It is my contention that there will be a 'market' for all these sizes. We should first review what these markets are.
On the smaller end, the LFTR, as a high temperature reactor, can provide process heat. A small chemical plant, requiring thousands of tons of steam an hour, can use a LFTR to provide this heat and, to electrically power the plant. A slightly larger version may be able to provide power and vast qualities of heat to an oil refinery or a tar-sands operation thus providing carbon-free process heat to what otherwise would be a huge carbon-spewing operation.
These smaller LFTRs, from 20 to 200 MWs could provide, also, site specific load balancing for a grid that has a lot of load in place but generation many hundreds of miles away. Using a 200 MW LFTR to 'anchor' the grid would be very helpful to any utility. Additionally these smaller LFTRs could be plopped down in various transmission substations to provide quick, peaking power or variable load changing that responds to frequency changes throughout the day.
Additionally, along the process heat scenarios, these small and, larger LFTRs can be used to cheaply crack sea water into various products including and most desirably, hundred of thousands of cubic meters of fresh, potable water for drinking and agriculture, thus allowing a huge increase in agricultural output in drier climates, like California, Egypt or Tunisia. Thus electrical generation would be, or could be, the co-generation product of such plants. Additionally, another such product from process heat could be the cracking of hydrogen from water using high-temperature electrolysis, thus providing yet another alternative fuel for automotive transport.
Larger LFTR units could be would be used for base-load generation. Phasing out gas and coal plants with big 1000+ MW units.
There are many uses for all sizes of LFTRs that are all designed basically the same. Energyfromthorium.com has papers and discussion on how all this works, so I won't go into basic LFTR technology here.
One thing that is important for this discussion to note, however, is that LFTRs, from the get go, are cheaper to produce, having a much higher power density than any currently running or under-construction Generation II or III Light Water Reactors. From the reactor core itself to the turbine, size is about 1/2 to 2/3 smaller, thus allowing for a cheaper, and therefore far more efficient, product based on size/cost per MW output. We are looking at, generally a similar ratio in cost reduction.
So...to the meat of the issue
It is my contention, or thesis, that there is a use for both the smaller scale, sub-300 MW LFTR units AND the larger, up though 1800MW LFTRs as well.
The argument is poised this way: is it cheaper (safer, easier, efficient, etc etc) to build, for example, 15 100 MW LFTRs vs one 1500 MW LFTR to achieve a 1500 MW requirement for a single location? This is the heart of the debate.
Charles Barton over at nucleargreen.blogspot.com and a keen observer of nuclear and 'renewable' energy costs. Many nuclear bloggers have as well. I'm not an economist, financial expert or engineer. My experience is simply one of a interested observer, and commentator, on energy issues. Charles is an advocate of the LFTR deployment being one of small reactors. He has many blog posts on this question and I urge all left-atomics readers to go to his site and look for these posts.
Advantages of Smaller LFTRs...
So...what ARE the advantages of a small, sub-300 MW, or sub-100 MW LFTR? Because the overall size of a LFTR is at least 1/2 the size of the equivalent LWR to start with, and these smaller lifters are 2/3 to 1/10 the out put, small LFTRs may able to be transported, in total, on three tractor-trailers or rail cars (reactor core/housing, turbine, generator). Given that construction costs of large, LWR amount to almost half the costs of a large reactor today, this is a tremendous savings.
Additionally, almost the entire module assemblies may well be assembled in a factory, on a production line similar to that of the building of passenger and cargo aircraft today. Production costs for smaller, but quantitatively greater, components ARE the cheaper form of production based on economy of scale.
The reality, however, is that even for larger reactors of the LFTR variety, almost all their components are also factor built, just like in today's' fleet of reactors. There is something of a 'production myth' that these large reactors are somehow built more primitively. Almost every single component in a modern nuclear reactors is built 'on a line'. But even small pumps, motor, controls, etc are built 'by hand', albeit in a factory. A 100 HP pump is hand assembled for the most part, albeit the parts that compose the whole pump are more likely to be manufactured on a true assembly line process.
I suspect as we parse out the true production costs for larger and small components, even the smaller ones for the small LFTRs that the costs are not that different from the larger units.
The advantage for the smaller LFTR is that many more modules for different aspects of the plant can be cobbled together in a factory as opposed to hand assembled on site. Generally, the rule holds that a system that comes 'ready-to-install' it is cheaper than one assembled by hand on site. A CO2 fire suppression system is an example of this. While the pipe runs to each piece of electrical equipment has to be hand run, the CO2 discharge assembly, composed of dozens of small, say 1" diameter, pipe runs, regulators, pilot and stop valves, on unit that is, say, 10 feet by 10 feet, can easily be built in a factory and shipped to the site. But in a bigger plant, where you need pipe discharge valves and runs that use use, say, 2 and 3" diameter pipe and valves, and is 20 feet by 15 feet, then assembly on site may have to occur. Thus an increase in expense.
But If...
But if...and this is the big "IF", this bigger assembly which can service a 1000 MW plant is more expensive per unit, say by a factor of 3 (for the labor it takes to assemble it on site as opposed to a factory, and the large individual sub-components cost more as well), but you need 10 of the smaller cheaper assemblies for the 10 separate LFTR units, then those cost savings for the 10 smaller units disappear and are actually more expensive by a factor of 3.
So, what all of us need to do, and it would help if actual operations engineers, construction engineers, and manufacturing engineers chimed in here, is actually parse out the true costs of a complete, say, 100MW LFTR and that of a 1800MW LFTR. I argue that it will be *impossible* to determine until all sized units are built in mockups to scale, during the R&D that precedes actual deployment. We simply will not know.
Some more things to think about. A big expense for any reactor and turbine generator set are controls. This including things like monitoring radiation, temperatures throughout the reactor-to-heat exchanger loops to the turbine and, of course, volts/amps/watts on the generator. A generator, regardless of the size, has a voltage relay device that reads the system voltage and the voltage of the generator. A set of leads from the high and low side of the transformer banks "potential transformers" (PTs) runs back to a relay and monitor in the plant's control room. There are *hundreds* of these sorts of systems on any modern power plant, regardless if they are geothermal, conventional steam plants or hydro units.
The PTs generally are all the same size and installation uses the same methods. Their testing, 'stressing' and maintenance are all the same based on conditions at the plant. So, regardless of the size of the LFTR, they will all get the same sort of PTs and all the costs associated with them. So, for 1500 MW plant, the costs for 15 100 MW LFTRs for the PT sets required are *likely* to be 15 times more expensive than for the 1500 MW unit (to be fair, there may be a larger redundancy for the larger units as they often have more than one transformer bank). But even if divided by 2, the costs, or "economy of scale", is now reversed and favor the single larger 1500 MW unit.
And this, fellow nukes, is my point. All these factors have to be taken into account when supplying what the customer wants in terms of gross MWs installed in a single location.
To be fair, this is VERY, very simplified presentation of counter-positions. But this does need to be seriously parsed out, eventually.
I believe the real advantage of the smaller units will be it's flexibility in installations, where they can be located, how, etc. Many times utilities want the bigger units because the are compelled by many reasons to group their "MWs together" in one big unit. The smaller LFTR modules can be "distributed" for, in some/many cases, a more reliable grid. Thus the same 1500 MWs the big public utility may want can now be distributed over a greater, and therefore more reliable area. Because the price difference and environmental impact for doing this with conventional fossil plants was prohibitive, you did not see this occur. Thus the LFTR gives advantage because if it's "infinite scalability" to distribute it's power production.
Secondly, and more importantly, while I will continue to put an "equal sign" between the big and small versions of the LFTRs that will be deployed in the future, for many, perhaps most, parts of the world, the smaller LFTR versions will be highly desirable. Many countries have electric grids that have, because of the legacy of colonialism and imperialism, war and revolution, dilapidated, incomplete or basically retarded development and mass under or non-electrified sections of their countries. This is one of the reasons why India is still interested in nuclear energy in *under* 700 MW units.
A grid that is relying on 200 MWs of diesel powered in 10 locations and subject to blackouts, fuel shortages, can add, for example, as part of a rural and small town electrification program, a set of, say, 3 100 MW LFTRs to boost over all capacity to 500 MWs while load increases from 200 to, say, 300 over a year or two. Multiple non-joined grids could be developed this way and then joined as transmission finally ties the country or region together. Smaller, 50 MW LFTRs can be installed incrementally. Eventually you'd have a larger, regional grid composed of about a dozen or more variable sized LFTRs. As the economy improves because of the addition to the *physical* economy of the nation gets stronger, larger LFTR units could be installed in more centralized locations with the smaller ones previously installed used to balance frequency/voltage and provide peaking power.
Monday, April 27, 2009
Toward a Thorium Economy: the Future of Nuclear Energy Part II: the technology. A discussion with D. Walters.
Toward a Thorium Economy: the Future of Nuclear Energy
Part II: the technology. A discussion with D. Walters.
"So, David, can you explain more on the "Thorium Economy" and what you mean by that now that we pave the basics of the technology down?"
Sure. Just remember what was part of Part I was only the basics, it can be a far more complex system and one should read more. Going to energyfromthorium.com will help increase your knowledge of the subject so will you do that?
"Sure, thanks."
Not a problem. So, let's continue.
Given that the LFTR can provide energy based on the abundance and easy processing of it's fuel, Thorium (Th), we need to talk some more about the technology.
"...but you said..."
I know, but there is a bit more. Because of the design of the LFTR, it can produce the same amount of power as a Light Water Reactor for a much, smaller footprint. Probably 1/3 or even smaller on a megawatt to megawatt basis. This is important because it will lead us to discuss how we can deploy the LFTR and for what kind of usages.
"Usages? You mean to make electricity."
Yes, but there is more. The LFTR can produce a tremendous amount of heat, and this heat can be used directly in a variety of energy intensive industries, like oil refining and chemical production, desalination of sea water, synthetic fuels and a variety of other purposes. And, of course generate electricity. And, do it very cheaply.
So we have smaller sizes of LFTRs and, it's process heat, we can deploy these reactors in thousands of industries around the world.
"Wait. Go back. What's this 'synthetic fuel' you mentioned?"
Syn-fuel can be made by combining hydrogen, carbon and oxygen atoms in the proper chemical compound. With enough process heat from nuclear power plants, specially our thorium powered LFTR, we can "thermo-chemically" crack hydrogen from water. The H2 can then be used directly as a fuel, or, be combined with carbon drawn from atmospheric CO2 to create either methanol, a gasoline substitute, or di methyl ether, a diesel substitute. Most estimates see approx $2/gal to make this. Not to shabby.
In effect, we can replace all liquid fuels, which is about 50% of the worlds energy form, for cars, trucks, trains, planes and even motorcycles, with synthetic fuel made in part from water and atmospheric CO2. A totally carbon neutral, zero particulate, fuel regime for the world.
Additionally the LFTR can be mass produced in factories, that is the smaller, 50 MW or there abouts, size, or as big as the biggest any turbine-generator around, the 1800 MW Alstrom. The scalability is, basically 'total'...from 30 MW (or smaller) totally sealed "LFTR batteries" that are fueled once and run for, say, 30 years, to the bigger plants.
Because of the ability to use what is called a "Brayton cycle" turbine (like the design of a jet engine), much less cooling water is needed. In fact, the waste heat from the bottom of this cycle can actually be put to use directly in flash-distillers to crack fresh water from sea-water. Not to shabby, huh? The LFTR can actually solve, almost completely, the major world wide issue fresh water shortages (for drinking and irrigation).
"OK, I'm impressed".
Is that why you are down on one knee?
"No, I have to scratch my ankle"
OK. So, do you want to hear more?
"OK".
The Thorium Economy concept is a paradigm of the physical economy of the planet that can say, with optimism if not certainty, that the planet can be fueled totally by one form of energy derived from the use of the element Th in the form of molten salt reactors, called the Liquid Fluoride Thorium Reactor or LFTR for short.
"Yeah but what about "diversity", "conservation/efficiency" "sustainability" and "decentralization? What about that, huh?"
What's with the attitude? Look, lets define what the issues are vis-a-vis energy before we get into catch-phrases and haikus, OK?
"Alright, sorry".
Don't worry about. The issues are these, but they are not ranked in order of importance, they are all important:
1. Carbon particulate. This is what kills people everyday as the result of the burning of coal and, diesel fuel. It's the cause of mercury and other heavy metal poisoning world wide, on land and in the oceans. See those warning signs about mercury at fish stores? Coal. It kills, in the U.S., 30,000 people a year and at least 10 times that number are made ill.
2. CO2. If you don't know this as an issue, please turn your computer off and go away, I don't want educate you on this. Thank you for reading this far.
3. Energy abundance. Every advance in human culture has come about as the result of the development of the productive forces, that is, increasing skills in labor, the number of workers, the efficiency of applied technology in industry, the ability of industry to produce commodities and higher technologies that make our lives better and less drudgery, in a healthier and safer lifestyle. This has been, historically, dependent upon the increase in energy efficiency through the use of denser and denser, more efficient generation of energy. The more abundant the energy, the more more advanced civilization can become.
The world is awash in poverty and underdevelopment. It is most easily measured in two ways:
A. Calorie intake and
B. Kilowatt hour usage over a year.
The average KW usage in the developed world is around 2,000 - 6,000 a year. Yes, it's used inefficiently and we can talk about that, but over all, this is about 10 times the amount used in the underdeveloped world. What does this mean practically?
"No flat screen TVs in Gabon or margarita mixers in Nepal?"
Don't be an idiot.
"Sorry..."
It means that simple things like a light-switch, which gives students the ability to read after the sun goes down, or the use of a refrigerator, to prolong foodstuffs longevity and store medicines, are simply absent, with the resultant lowering of life spans and increases in diseases. That's what it means. The more electrical energy there is, the healthier we can become, the more prosperous our a society, the higher the cultural level our people can achieve.
Oh, and the internet, home and school computers, vaccine production, operations, recordable music, etc etc. We don't think about that often in the U.S. or other better developed countries but electricity provides the material basis for advanced civilization. Without, our life expectancy drops, education drops, health care drops or disappears.
This is whey the catch phases you use above are completely secondary to the the points A. and B. I noted after that. We should be for conservation and efficiency simply because it's a cheap thing to do. Why waste resources? But it should be done in the frame work of a massive, truly massive expansion of the productive forces as I described above based on the ability to produce super-abundant sources of energy. Everything else should be subordinate to that and that alone.
"...diversity and decentralization?"
Oh, yeah. OK. So, there is nothing intrinsically 'good' about diversity. Many, especially those on the political left, tend to see diversity of energy as some sort of liberal paradigm extended from our multi-cultural society. It's a false analogy by them to do this. Brazil, to site a VERY culturally diverse society, derives almost ALL it's electrical energy from hydro-electric power. What is wrong with this? Absolutely nothing. It's essentially carbon/particulate free and it's totally renewable. Remember the two issues that are really under discussion. This was my point "1." Diversity of energy sources is a paradigm brought on by those who reject the vision of energy abundance and believe that either we have no choice and we have to ration energy (those that believe in energy scarcity) or those that advocate intermittent and unreliable sources of energy in the renewable crowd, like wind and solar. The renewable energy paradigm is basically based on energy scarcity, not abundance, thus a major difference.
Decentralization is basically the same as diversity. There is no intrinsic value in 'decentralization' as it's often not defined and can mean anything to any one. Does it mean people "living of the grid and cutting wood for warmth"? Does it mean every community having it's own wind farm some place praying for the wind to keep blowing? Does it mean having wind and solar farms spread about the land tied together by so-called "smart grid" technology and high voltage DC lines?
Nuclear energy, especially LFTR nuclear energy, can be anything anyone wants as it can be located almost anywhere and give reliable power 24/7 365 days a year.
"How do we get there, then, from here...?"
Good question. That will be part III
Part II: the technology. A discussion with D. Walters.
"So, David, can you explain more on the "Thorium Economy" and what you mean by that now that we pave the basics of the technology down?"
Sure. Just remember what was part of Part I was only the basics, it can be a far more complex system and one should read more. Going to energyfromthorium.com will help increase your knowledge of the subject so will you do that?
"Sure, thanks."
Not a problem. So, let's continue.
Given that the LFTR can provide energy based on the abundance and easy processing of it's fuel, Thorium (Th), we need to talk some more about the technology.
"...but you said..."
I know, but there is a bit more. Because of the design of the LFTR, it can produce the same amount of power as a Light Water Reactor for a much, smaller footprint. Probably 1/3 or even smaller on a megawatt to megawatt basis. This is important because it will lead us to discuss how we can deploy the LFTR and for what kind of usages.
"Usages? You mean to make electricity."
Yes, but there is more. The LFTR can produce a tremendous amount of heat, and this heat can be used directly in a variety of energy intensive industries, like oil refining and chemical production, desalination of sea water, synthetic fuels and a variety of other purposes. And, of course generate electricity. And, do it very cheaply.
So we have smaller sizes of LFTRs and, it's process heat, we can deploy these reactors in thousands of industries around the world.
"Wait. Go back. What's this 'synthetic fuel' you mentioned?"
Syn-fuel can be made by combining hydrogen, carbon and oxygen atoms in the proper chemical compound. With enough process heat from nuclear power plants, specially our thorium powered LFTR, we can "thermo-chemically" crack hydrogen from water. The H2 can then be used directly as a fuel, or, be combined with carbon drawn from atmospheric CO2 to create either methanol, a gasoline substitute, or di methyl ether, a diesel substitute. Most estimates see approx $2/gal to make this. Not to shabby.
In effect, we can replace all liquid fuels, which is about 50% of the worlds energy form, for cars, trucks, trains, planes and even motorcycles, with synthetic fuel made in part from water and atmospheric CO2. A totally carbon neutral, zero particulate, fuel regime for the world.
Additionally the LFTR can be mass produced in factories, that is the smaller, 50 MW or there abouts, size, or as big as the biggest any turbine-generator around, the 1800 MW Alstrom. The scalability is, basically 'total'...from 30 MW (or smaller) totally sealed "LFTR batteries" that are fueled once and run for, say, 30 years, to the bigger plants.
Because of the ability to use what is called a "Brayton cycle" turbine (like the design of a jet engine), much less cooling water is needed. In fact, the waste heat from the bottom of this cycle can actually be put to use directly in flash-distillers to crack fresh water from sea-water. Not to shabby, huh? The LFTR can actually solve, almost completely, the major world wide issue fresh water shortages (for drinking and irrigation).
"OK, I'm impressed".
Is that why you are down on one knee?
"No, I have to scratch my ankle"
OK. So, do you want to hear more?
"OK".
The Thorium Economy concept is a paradigm of the physical economy of the planet that can say, with optimism if not certainty, that the planet can be fueled totally by one form of energy derived from the use of the element Th in the form of molten salt reactors, called the Liquid Fluoride Thorium Reactor or LFTR for short.
"Yeah but what about "diversity", "conservation/efficiency" "sustainability" and "decentralization? What about that, huh?"
What's with the attitude? Look, lets define what the issues are vis-a-vis energy before we get into catch-phrases and haikus, OK?
"Alright, sorry".
Don't worry about. The issues are these, but they are not ranked in order of importance, they are all important:
1. Carbon particulate. This is what kills people everyday as the result of the burning of coal and, diesel fuel. It's the cause of mercury and other heavy metal poisoning world wide, on land and in the oceans. See those warning signs about mercury at fish stores? Coal. It kills, in the U.S., 30,000 people a year and at least 10 times that number are made ill.
2. CO2. If you don't know this as an issue, please turn your computer off and go away, I don't want educate you on this. Thank you for reading this far.
3. Energy abundance. Every advance in human culture has come about as the result of the development of the productive forces, that is, increasing skills in labor, the number of workers, the efficiency of applied technology in industry, the ability of industry to produce commodities and higher technologies that make our lives better and less drudgery, in a healthier and safer lifestyle. This has been, historically, dependent upon the increase in energy efficiency through the use of denser and denser, more efficient generation of energy. The more abundant the energy, the more more advanced civilization can become.
The world is awash in poverty and underdevelopment. It is most easily measured in two ways:
A. Calorie intake and
B. Kilowatt hour usage over a year.
The average KW usage in the developed world is around 2,000 - 6,000 a year. Yes, it's used inefficiently and we can talk about that, but over all, this is about 10 times the amount used in the underdeveloped world. What does this mean practically?
"No flat screen TVs in Gabon or margarita mixers in Nepal?"
Don't be an idiot.
"Sorry..."
It means that simple things like a light-switch, which gives students the ability to read after the sun goes down, or the use of a refrigerator, to prolong foodstuffs longevity and store medicines, are simply absent, with the resultant lowering of life spans and increases in diseases. That's what it means. The more electrical energy there is, the healthier we can become, the more prosperous our a society, the higher the cultural level our people can achieve.
Oh, and the internet, home and school computers, vaccine production, operations, recordable music, etc etc. We don't think about that often in the U.S. or other better developed countries but electricity provides the material basis for advanced civilization. Without, our life expectancy drops, education drops, health care drops or disappears.
This is whey the catch phases you use above are completely secondary to the the points A. and B. I noted after that. We should be for conservation and efficiency simply because it's a cheap thing to do. Why waste resources? But it should be done in the frame work of a massive, truly massive expansion of the productive forces as I described above based on the ability to produce super-abundant sources of energy. Everything else should be subordinate to that and that alone.
"...diversity and decentralization?"
Oh, yeah. OK. So, there is nothing intrinsically 'good' about diversity. Many, especially those on the political left, tend to see diversity of energy as some sort of liberal paradigm extended from our multi-cultural society. It's a false analogy by them to do this. Brazil, to site a VERY culturally diverse society, derives almost ALL it's electrical energy from hydro-electric power. What is wrong with this? Absolutely nothing. It's essentially carbon/particulate free and it's totally renewable. Remember the two issues that are really under discussion. This was my point "1." Diversity of energy sources is a paradigm brought on by those who reject the vision of energy abundance and believe that either we have no choice and we have to ration energy (those that believe in energy scarcity) or those that advocate intermittent and unreliable sources of energy in the renewable crowd, like wind and solar. The renewable energy paradigm is basically based on energy scarcity, not abundance, thus a major difference.
Decentralization is basically the same as diversity. There is no intrinsic value in 'decentralization' as it's often not defined and can mean anything to any one. Does it mean people "living of the grid and cutting wood for warmth"? Does it mean every community having it's own wind farm some place praying for the wind to keep blowing? Does it mean having wind and solar farms spread about the land tied together by so-called "smart grid" technology and high voltage DC lines?
Nuclear energy, especially LFTR nuclear energy, can be anything anyone wants as it can be located almost anywhere and give reliable power 24/7 365 days a year.
"How do we get there, then, from here...?"
Good question. That will be part III
Saturday, April 25, 2009
Toward a Thorium Economy: the Future of Nuclear Energy Part I
Toward a Thorium Economy: the Future of Nuclear Energy
Part I: the technology. A discussion with D. Walters.
This is not a diary on what we need to do tomorrow to solve fossil fuel carbon particle caused death or an immediate solution to climate change (or even an entry on that debate). No, this is more or less along the same lines as other "Grand Plans" that are presented in the popular press like Scientific American and Greenpeace who try, through smoke and mirrors, to present a non-Nuclear future (but fail miserably).
This Thorium Economy Grand Plan will not use smoke or mirrors or engage in scientific or economic make-believe. It is designed to look outward, forward, to a "Physical Economy" that is based on heavy metal fission with an abundance, not scarcity, of energy.
[I should point out here that I am a left-wing Socialist. That's with a capital "S". I helped found the Marxists Internet Archive and Left-Atomics.blogspot.com. I'm not a liberal, I'm a believer in working class power and an end to religion of the "Marketplace". I want to make this clear from the get-go: I'm a big advocate of "Public Power" and a nationalized energy system. But I oppose those that under capitalism would hinder the development of technological progress because of their unscientific understanding of technology, physics and the need to provide a material basis for a future that puts human needs ahead of profits and is based on a rising, not shrinking standard of living for the world. 'nuf said on politics]
The Liquid Fluoride Thorium Reactor is a Generation IV reactor. The R&D for the basic technology has already been proven and deployed in test reactors at Oak Ridge National Labortories in the 1960s and early 1970s. Because of politics, the link between the Military and the "Uranium Industrial Complex" that sought to marry military nuclear WMD with civilian nuclear energy through the original Fast Breeder Reactor experiments, technologies that did not rely on uranium and produce weapons grade plutonium, like the LFTR, was denied funding. The old Atomic Energy Commission killed the LFTR (called various names like the Molten Salt Reactor) and fired Dr. Alvin Weinberg (holder of the Light Water Reactor patent and original herald of the issue of global warming and who gave Ralph Nader his first 'class' on the issue in the 1970s), then head of the MSR experiment team.
Most of the information garnered here comes from the two leading on line sites for LFTR technology: energyfromthorium.com and The Nuclear Green Revolution [nucleargreen.blogspot.com] sites. Both assemble a multitude of professional engineers and alternative (REAL alternative) energy advocates who are trying to publicize the issue of LFTR and how this does in fact represent a "Thorium Bullet" to the future of the world's energy needs.
This also is not the only diary/blog here that I've done on the LFTR. There will be more as our job is to publicize and develop LFTR concepts and get serious funding to re-start and then jumpstart the LFTR R&D deployment program via either the Department of Energy and/or University/Academic interest and/or private investors and entrepreneurial type interests. We don't really care. We have our preferences (Public Power) but it is the technology I we are focusing on here.
Thorium is No. 90 on the Periodic Table. Its symbol is "Th". Two to the left of Uranium. It is a fertile, not fissile material. This means that while the atoms of Th can split and produce more nuetrons when hit by a nuetron, it can under nuclear 'alchemy' turn into something called "protractium". Protractium, after 27 or so days, decays into another isotope of uranium called "U-233". This material makes excellent fuel for a nuclear reactor. That is the basics.
Our intervenor asks:
"More?"
OK, since you asked. There is 4 times more Th than uranium in the earth's crust. But wait! There is more! The basis of the LFTR is that it 's a reactor where the fuel is suspended in liquid fluoride salt and thus, because it's liquid, it can be chemically treated. This means that the nasty fission producets and anticides produced by fissioning of U233 can easily be removed.
"But David, that's W-A-S-T-E!".
Yes, it is. But the differences is that the LFTR burns up 99.9% of the U233 and leaves very little waste behind.
"Explain this please?".
OK, the LFTR is a BREEDER. It doesn't breed vast qunatiies of plutonium like a "Fast Breeder". This is what is called a 'thermal spectrum breeder'. Actually it can also be a 'fast breeder' and anything in between. But the basis of this is that Th is totally fertile and ALL of it can be turned into U-233. Unlike a light water reactor (LWR) where only a very small percentage of the overall uranium is used for energy, the LFTR uses all of the Th injected into it.
"So what?"
What do you mean "So What?". This means that you don't need a lot of Th. In fact, you need VERY little of it. The average LWR uses about 30 tons of uranium fuel for a GW year (I'm NOT going to explain what that is, you look it up, ok?). Suffice it to say about the energy out put in electricity for a large power plant that can power a city of a million for about one year. A lot of energy for a mere 30 tons. But that is for a LWR. The LWR then produced about 30 tons a year of Spent Nuclear Fuel, or, coloquealy speaking, "nuclear waste".
The LFTR is different. It uses only ONE TON a year. That's it. And not refined, enriched or otherwise expensive 'manufactured' fuel like in a LWR but RAW Th with only the soil and dirt removed through standard low-energy using milling processes like removing chaf from the wheat. Really. One Ton! For One GW Year! This means that LFTR can supply a city of one million people for a year with enough electrical generation on a fuel that works out to be 6.5 lbs of fuel a day. 4 people with shovels can mine enough of this Th for a LFTR to run for a 1 GW year by digging Th ore between morning coffee break and lunch in one day. See where I'm going with this?
Secondly, but as importantly, because it's one ton of Th a year that goes in, a little less than one ton of SNF comes out. And because the anticides and fission products are removed chemically through recycled chemical reprocessing train on site, never leaving the LFTR compound, the SNF is only dangerous for about 300 years after which the SNF, in the form of a metal, can simply be...recycled for other non-nuclear purposes. The LWR produces over 20 tons of highly radioactive long lived wastes (which is still very little compared to polluting wastes from coal and gas plants).
"But you said it was a 'Breeder'".
Yes, you are correct, and I digressed. The breeding ratio of the LFTR is can be anywhere from <1 to 1.09, meaning it produces as much fuel as it uses or a little bit more, making a doubling of the actual fuel in the form of U233 every 9 years or so. This means we only have to add that 1 ton of Th a year and we actually gain on the fuel used, the U233 for start up charges for new LFTRs.
"What's the start up charge"?
It's the initial 'charge' or supply of fissionable material. Remember, Th is fertile, it can decease into fissionable material, but only after 27 days. So each new LFTR needs needs a charge of something fissionable. This can be highly enriched U235, Plutonium 239 from weapons or the waste of LWRs, or U233 produced in other Th breeder reactors like the LFTR.
"So we need only that 1 ton of Th per gigawatt of power for a year?".
Now you are getting it.
"How much is there? We keep hearing that their are limits to uranium fuel..."
Th is 4 times as more abundant than say, Uranium. The U.S. in particular is blessed with hundreds of thousands of tons of it. The US gov't had refined during the 1960s and 1970s about 3500 tons of Th which are buried in a shallow vault in Nevada. That 3500 tons alone can be used to run 100 1 GW (1,000 MW) LFTR type reactors for 35 years each. 100GWs is about how much nuclear or, 1/5 of the US energy supply. And, we have 200 times that amount that we know if.
"What do you mean "that we know of"?"
No looks for it any more and so we don't know if there are more economically recoverable reserves because we simply haven't prospected for it in the last 30 years. This also true with other heavy metal fuels like uranium.
"David, what then is in Part II of this discussion?"
Part II will deal with both techinical and political aspects of this struggle for a Thorium Economy and will define better what we mean by a "Thorium Economy", what it would look like, how we can get there.
END PART I
Part I: the technology. A discussion with D. Walters.
This is not a diary on what we need to do tomorrow to solve fossil fuel carbon particle caused death or an immediate solution to climate change (or even an entry on that debate). No, this is more or less along the same lines as other "Grand Plans" that are presented in the popular press like Scientific American and Greenpeace who try, through smoke and mirrors, to present a non-Nuclear future (but fail miserably).
This Thorium Economy Grand Plan will not use smoke or mirrors or engage in scientific or economic make-believe. It is designed to look outward, forward, to a "Physical Economy" that is based on heavy metal fission with an abundance, not scarcity, of energy.
[I should point out here that I am a left-wing Socialist. That's with a capital "S". I helped found the Marxists Internet Archive and Left-Atomics.blogspot.com. I'm not a liberal, I'm a believer in working class power and an end to religion of the "Marketplace". I want to make this clear from the get-go: I'm a big advocate of "Public Power" and a nationalized energy system. But I oppose those that under capitalism would hinder the development of technological progress because of their unscientific understanding of technology, physics and the need to provide a material basis for a future that puts human needs ahead of profits and is based on a rising, not shrinking standard of living for the world. 'nuf said on politics]
The Liquid Fluoride Thorium Reactor is a Generation IV reactor. The R&D for the basic technology has already been proven and deployed in test reactors at Oak Ridge National Labortories in the 1960s and early 1970s. Because of politics, the link between the Military and the "Uranium Industrial Complex" that sought to marry military nuclear WMD with civilian nuclear energy through the original Fast Breeder Reactor experiments, technologies that did not rely on uranium and produce weapons grade plutonium, like the LFTR, was denied funding. The old Atomic Energy Commission killed the LFTR (called various names like the Molten Salt Reactor) and fired Dr. Alvin Weinberg (holder of the Light Water Reactor patent and original herald of the issue of global warming and who gave Ralph Nader his first 'class' on the issue in the 1970s), then head of the MSR experiment team.
Most of the information garnered here comes from the two leading on line sites for LFTR technology: energyfromthorium.com and The Nuclear Green Revolution [nucleargreen.blogspot.com] sites. Both assemble a multitude of professional engineers and alternative (REAL alternative) energy advocates who are trying to publicize the issue of LFTR and how this does in fact represent a "Thorium Bullet" to the future of the world's energy needs.
This also is not the only diary/blog here that I've done on the LFTR. There will be more as our job is to publicize and develop LFTR concepts and get serious funding to re-start and then jumpstart the LFTR R&D deployment program via either the Department of Energy and/or University/Academic interest and/or private investors and entrepreneurial type interests. We don't really care. We have our preferences (Public Power) but it is the technology I we are focusing on here.
Thorium is No. 90 on the Periodic Table. Its symbol is "Th". Two to the left of Uranium. It is a fertile, not fissile material. This means that while the atoms of Th can split and produce more nuetrons when hit by a nuetron, it can under nuclear 'alchemy' turn into something called "protractium". Protractium, after 27 or so days, decays into another isotope of uranium called "U-233". This material makes excellent fuel for a nuclear reactor. That is the basics.
Our intervenor asks:
"More?"
OK, since you asked. There is 4 times more Th than uranium in the earth's crust. But wait! There is more! The basis of the LFTR is that it 's a reactor where the fuel is suspended in liquid fluoride salt and thus, because it's liquid, it can be chemically treated. This means that the nasty fission producets and anticides produced by fissioning of U233 can easily be removed.
"But David, that's W-A-S-T-E!".
Yes, it is. But the differences is that the LFTR burns up 99.9% of the U233 and leaves very little waste behind.
"Explain this please?".
OK, the LFTR is a BREEDER. It doesn't breed vast qunatiies of plutonium like a "Fast Breeder". This is what is called a 'thermal spectrum breeder'. Actually it can also be a 'fast breeder' and anything in between. But the basis of this is that Th is totally fertile and ALL of it can be turned into U-233. Unlike a light water reactor (LWR) where only a very small percentage of the overall uranium is used for energy, the LFTR uses all of the Th injected into it.
"So what?"
What do you mean "So What?". This means that you don't need a lot of Th. In fact, you need VERY little of it. The average LWR uses about 30 tons of uranium fuel for a GW year (I'm NOT going to explain what that is, you look it up, ok?). Suffice it to say about the energy out put in electricity for a large power plant that can power a city of a million for about one year. A lot of energy for a mere 30 tons. But that is for a LWR. The LWR then produced about 30 tons a year of Spent Nuclear Fuel, or, coloquealy speaking, "nuclear waste".
The LFTR is different. It uses only ONE TON a year. That's it. And not refined, enriched or otherwise expensive 'manufactured' fuel like in a LWR but RAW Th with only the soil and dirt removed through standard low-energy using milling processes like removing chaf from the wheat. Really. One Ton! For One GW Year! This means that LFTR can supply a city of one million people for a year with enough electrical generation on a fuel that works out to be 6.5 lbs of fuel a day. 4 people with shovels can mine enough of this Th for a LFTR to run for a 1 GW year by digging Th ore between morning coffee break and lunch in one day. See where I'm going with this?
Secondly, but as importantly, because it's one ton of Th a year that goes in, a little less than one ton of SNF comes out. And because the anticides and fission products are removed chemically through recycled chemical reprocessing train on site, never leaving the LFTR compound, the SNF is only dangerous for about 300 years after which the SNF, in the form of a metal, can simply be...recycled for other non-nuclear purposes. The LWR produces over 20 tons of highly radioactive long lived wastes (which is still very little compared to polluting wastes from coal and gas plants).
"But you said it was a 'Breeder'".
Yes, you are correct, and I digressed. The breeding ratio of the LFTR is can be anywhere from <1 to 1.09, meaning it produces as much fuel as it uses or a little bit more, making a doubling of the actual fuel in the form of U233 every 9 years or so. This means we only have to add that 1 ton of Th a year and we actually gain on the fuel used, the U233 for start up charges for new LFTRs.
"What's the start up charge"?
It's the initial 'charge' or supply of fissionable material. Remember, Th is fertile, it can decease into fissionable material, but only after 27 days. So each new LFTR needs needs a charge of something fissionable. This can be highly enriched U235, Plutonium 239 from weapons or the waste of LWRs, or U233 produced in other Th breeder reactors like the LFTR.
"So we need only that 1 ton of Th per gigawatt of power for a year?".
Now you are getting it.
"How much is there? We keep hearing that their are limits to uranium fuel..."
Th is 4 times as more abundant than say, Uranium. The U.S. in particular is blessed with hundreds of thousands of tons of it. The US gov't had refined during the 1960s and 1970s about 3500 tons of Th which are buried in a shallow vault in Nevada. That 3500 tons alone can be used to run 100 1 GW (1,000 MW) LFTR type reactors for 35 years each. 100GWs is about how much nuclear or, 1/5 of the US energy supply. And, we have 200 times that amount that we know if.
"What do you mean "that we know of"?"
No looks for it any more and so we don't know if there are more economically recoverable reserves because we simply haven't prospected for it in the last 30 years. This also true with other heavy metal fuels like uranium.
"David, what then is in Part II of this discussion?"
Part II will deal with both techinical and political aspects of this struggle for a Thorium Economy and will define better what we mean by a "Thorium Economy", what it would look like, how we can get there.
END PART I
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