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#26 2021-03-11 10:33:37

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,361

Re: Hydrogen from Nuclear Fission Economy

SpaceNut,

There are a host of factors that determine reactor fabrication and operational costs, as well as maintenance issues.  The reactor surface area to volume ratio and type of coolant used significantly factor into thermal efficiency, therefore size, operational costs, and the potential risk of a melt down.  Smaller reactors are less thermally efficient than larger ones if both are operated at the same temperature, but far less costly to fabricate, maintain, and decommission.  With good basic design, smaller reactors are also less likely to melt down, with or without operator intervention (Fukushima) or interference (Chernobyl).  We have reactors that use H2O, D2O, CO2, molten salts like FLiBe, and liquid metals such as NaK and LBE as coolants.  The fissionable material selected significantly affects how long radioactive waste must be stored.  The half lives of the daughter products associated with fissioning U233 produced from Th232 are much shorter than those created from fissioning U235 and Pu239, for example, so less expense to store the end products of fission.  Reprocessing of fuel affects the total demand for new fuel, therefore fuel costs.  If the reactor design mixes the fuel and coolant in a slurry, then you don't have to reprocess fuel, although you still have to chemically separate the fission products that poison the chain reaction.  However, receiving nearly 100% of the original energy content from the fuel would be a huge technological leap forward and enormous operating cost reduction.  We've actually done this in the past, but there are monied interests who want to ensure that we continually purchase more fuel than is actually needed to produce the power output.  Even if those monied interests have their way, there are also certain types of reactors like the Canadian CANDU reactors that Robert pointed out in another thread, that burn natural Uranium, which is refined into metal oxide fuel but not enriched at all, meaning it's loaded into the reactor with the natural mix of U235 and U238.  However, that sets a minimum viable reactor size, which is quite large, and at odds with other aforementioned useful program goals.  That said, most types of commercial reactors use LEU.  Military reactors use HEU.

tahanson43206,

Producing pure Hydrogen is not that useful if the goal is to synthesize easily storable and transportable liquid fuels.  NH3 (Anhydrous Ammonia- for easy transport and storage of Hydrogen to Hydrogen cracking stations, aka Toyota Mirai "gas pumps") or C3H8 (Propane) works as a fuel for all gas or diesel piston engines, gas turbines, boilers, desalination plants, and lower cost (cheap catalyst) Alkaline or Solid Oxide fuel cells.  Apart from liquefying Hydrogen or Methane, all low storage density deeply cryogenic fuels are impractical for prototypical uses.

We should focus on CO2 capture and liquefaction using solar thermal (construction materials readily recyclable) or nuclear thermal power plants (long service life and minimal high level waste generation), synthesizing liquid fuels (Ammonia, Propane, Gasoline, Diesel, Kerosene) that are storable at room temperature (unlike Hydrogen and Methane), and development of CNT as an aerospace-qualified structural material.

Again, CO2 is 100% recyclable.  If we capture it after combustion or chemical reaction in a fuel cell, then we can use a solar thermal or nuclear thermal power plant to make more of it by combining it in a high heat and pressure vessel that combines CO2 / seawater / heat / pressure to synthesize new hydrocarbon chains.  We absolutely know that this works.  It's only "too expensive" because there's still hydrocarbons that can be extracted from the Earth for less money.  When that runs out, then we'd best have this technology scaled up or all of our battery issues (energy density, cell life, recyclability, enough raw resources pinned down) solved and implemented on a planet-wide scale.

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#27 2021-03-11 12:08:18

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,361

Re: Hydrogen from Nuclear Fission Economy

louis wrote:

These are just construction tonnages. You have to look at lifetime tonnages. How much tonnage is going in and how much waste is being produced with each system.

I'd be surprised if a large nuclear power station wasn't using a couple of tons of material a day (remember it's not just the power station - you have a large human infrastructure - offices, restaurants, WCs etc.). If I am right then that's 700 tons a year, or 28000 tons over a 40 year lifetime. A wind turbine keeps on turning without a great deal of human intervention - yes there will be input tonnages associated with maintenance but nothing like with a nuclear power station.

Louis,

Wind turbines in the northern US states last as little as 10 years before major refurbishment or replacement of components is required, and we already know that they require at least an order of magnitude more resources than nuclear.  The act of making a semiconductor of any kind, a photovoltaic cell being only one example, consumes around 100,000 times more input material than useful output semiconductor material.  There's another problem, though, and that's all the gas or battery production you intend to use to deal with the fact that your energy sources are so dilute.  If we include the natural gas or batteries in the total consumption tallies, then there's no contest whatsoever between nuclear and any other form of power.  The 700 tons of fresh fuel are a resource not being used for any other useful purpose, but the resource still exists, so those of us making rational rather than ideologically motivated arguments say we should use it.  Uranium and Thorium are only useful for generating electricity more efficiently than any other resource ever could, precisely because those resources are so energy-dense.

While you're correct about the fresh fuel consumption, it still doesn't matter unless the employees working at nuclear power plants cease to exist as living human beings merely because they're employed elsewhere, while consuming enormous quantities of coal / gas / oil / batteries to make up for the fact that nuclear materials are at least a million times more energy-dense.  This has to be one of the poorest arguments you've ever attempted to make here.

As someone who is intellectually honest, I must admit that there will likely be far more permanent high-paid employees going to work every day in nuclear power plants than employees going to work at wind farms or solar farms.  Fewer than 100 nuclear reactors supply just shy of 20% of America's electricity.  Those reactors directly employ 100,000 people and indirectly employ 475,000 people.  If we went 100% nuclear, then using simpleton math we'd employ 400,000 directly and 1,900,000 indirectly.

That said, all of those nuclear plant employees are going to one place.  If they live near the plant, as many of them do to make it easy to get to work, then transporting those 1,000 to 2,000 employees could be done with public transportation such as buses.  That's how we used to do it when we had fewer motor vehicles.  South Texas Nuclear Project has 1,200 employees.  The pay scale ranges between $56K and $140K a year.  Those are excellent middle class jobs.  You won't get rich, but you'll never go broke, either.  Many of their employees have college level education.  Mom can afford to stay home and raise her children and Dad can go work at the plant.  That was the way we used to do it, before our brain dead SJWs ruined social norms to distort the world to their dystopian worldviews.  My wife works like I do, but I've never once heard her say, "I really wish I could spend more time at work instead of with my children."  I hear the exact opposite quite often, though.

The people who installed the solar panels on my roof were all high school graduates or dropouts living paycheck to paycheck.  I think the sole person amongst them who had earned a college degree was their supervisor.  I guess if my goal was to exploit a bunch of working poor uneducated people, then I would make them all manual laborers installing solar panels and wind turbines for the rest of their lives so that wealthier Americans could afford to purchase the electricity that they could not.  In either case, all of those people operating the nuclear power plants continue to exist, with or without high paying STEM jobs that typically cause them to seek out college education so that they can learn about why protecting the environment is a useful goal, as well as the monetary wealth to educate their own children at a collegiate level.  I can't possibly fathom why we'd want more of that.

The US solar industry directly employs 250,000 people and solar supplies.  The pay scale can be every bit as high, but most of them, by numbers, who are installers, make between $30K and $40K per year, sometimes with benefits, which is nice, and very few of those people have college degrees, because they can't afford to go to college with $30K/yr salaries.  The US wind industry employs, I think, 100,000 to 110,000.  I'm almost certain that your next argument will be that wind and solar employ more people than nuclear, therefore it's better than nuclear due to the jobs created.  Those people are also consuming things and creating waste to transport and repair / refurbish / replace everything they install.

I don't want a future filled with barely-educated manual laborers who can scarcely afford to use the product or service that they produce.  Henry Ford had the correct model.  Nuclear power is the most efficient society-level pooling of labor, resources, and capital to produce the energy, the master resource, that technologically advanced human civilization requires, so that everyone can reap the benefits.

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#28 2021-03-11 13:11:08

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: Hydrogen from Nuclear Fission Economy

For kbd512 .... enjoyed your Post #27 in reply to Louis ...

Regarding the proposition of this topic .... Hydrogen is the feedstock for all kinds of value added products.

It is ** not ** necessary to sell the hydrogen a nuclear plant produces to the open market, although if the price is right then go for it.

Instead, it seems to me that a single nuclear reactor, situated as most are next to a river or a lake or the ocean, can support a nearby community of high value secondary products that can be stored until needed (a) or (b) the price is right.

In any case, ** real ** Boards of Directors of ** real ** nuclear plants are making these decisions today under market pressure.

I'd like to see reports of such decisions (and their benefits to shareholders) eventually show up in this topic.

(th)

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#29 2021-03-11 15:33:27

Terraformer
Member
From: Ceres
Registered: 2007-08-27
Posts: 3,800
Website

Re: Hydrogen from Nuclear Fission Economy

Extraction of Uranium from seawater

Firstly, pumping the seawater to extract this uranium would need more energy than what could be produced with the recuperated uranium. Then if trying to use existing industrial flow rates, as for example on a nuclear power plant, it appears that the annual possible quantity remains very low. In fact huge quantities of water must be treated. To produce the annual world uranium consumption (around 65,000 tU), it would need at least to extract all uranium of 21013tonnes of seawater, the volume equivalent of the entire North Sea.

Note that *current* consumption is 65 kilotonnes of uranium. If we tried delivering european level per capita energy consumption to the present world population, we would require a tripling of our global energy budget, which nuclear provides a tenth at present.

All this is to say, switching to nuclear would buy us maybe a decade (a lot of the energy is wasted due to inefficiencies, but it's not orders of magnitude) before we burn through our resources, so the only way we're going nuclear any time soon is if we have a crash Manhattan project to develop breeder reactors and other such new types.

Absent the will for such a program - which needs an advanced, competent, and functional country to do it - we're going down.


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#30 2021-03-11 15:56:04

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Hydrogen from Nuclear Fission Economy

kbd512 wrote:


Louis,

Wind turbines in the northern US states last as little as 10 years before major refurbishment or replacement of components is required, and we already know that they require at least an order of magnitude more resources than nuclear.  The act of making a semiconductor of any kind, a photovoltaic cell being only one example, consumes around 100,000 times more input material than useful output semiconductor material.  There's another problem, though, and that's all the gas or battery production you intend to use to deal with the fact that your energy sources are so dilute.  If we include the natural gas or batteries in the total consumption tallies, then there's no contest whatsoever between nuclear and any other form of power.  The 700 tons of fresh fuel are a resource not being used for any other useful purpose, but the resource still exists, so those of us making rational rather than ideologically motivated arguments say we should use it.  Uranium and Thorium are only useful for generating electricity more efficiently than any other resource ever could, precisely because those resources are so energy-dense.

While you're correct about the fresh fuel consumption, it still doesn't matter unless the employees working at nuclear power plants cease to exist as living human beings merely because they're employed elsewhere, while consuming enormous quantities of coal / gas / oil / batteries to make up for the fact that nuclear materials are at least a million times more energy-dense.  This has to be one of the poorest arguments you've ever attempted to make here.

In the UK we are currently seeing the demise of many high street shops as online shopping takes the place of physical shopping to a large degree. Now a retail economist will explain this by saying online shopping uses far fewer resources e.g. salaries for shop workers, floor space, staff facilities, heating and lighting etc etc. They don't say "Well human beings still have to live so we shouldn't take account of savings on servicing human beings." So not a poor or irrelevant argument at all. Nuclear power stations are consuming resources all the time, 24/7. If the staff car park needs re-tarmacing every ten years that is a valid material input to put into your calculation.

I have never heard of modern wind turbines needing major replacements as a matter of course during their 20 years advertised lifteimes. Think I would need some links. Perhaps it's been a design issue with a particular turbine. And by the way it's obvious lots of modern wind turbines are going to be operating way beyond their 20-25 year lifetimes. When they do, the cost of electricity they generate will plummet as with old LWRs which have paid back their initial investment. What's good for nuclear is good for wind. Once wind energy is a mature technology this is going to feed into lower costs across the board.

As someone who is intellectually honest, I must admit that there will likely be far more permanent high-paid employees going to work every day in nuclear power plants than employees going to work at wind farms or solar farms.  Fewer than 100 nuclear reactors supply just shy of 20% of America's electricity.  Those reactors directly employ 100,000 people and indirectly employ 475,000 people.  If we went 100% nuclear, then using simpleton math we'd employ 400,000 directly and 1,900,000 indirectly.

That said, all of those nuclear plant employees are going to one place.  If they live near the plant, as many of them do to make it easy to get to work, then transporting those 1,000 to 2,000 employees could be done with public transportation such as buses.  That's how we used to do it when we had fewer motor vehicles.  South Texas Nuclear Project has 1,200 employees.  The pay scale ranges between $56K and $140K a year.  Those are excellent middle class jobs.  You won't get rich, but you'll never go broke, either.  Many of their employees have college level education.  Mom can afford to stay home and raise her children and Dad can go work at the plant.  That was the way we used to do it, before our brain dead SJWs ruined social norms to distort the world to their dystopian worldviews.  My wife works like I do, but I've never once heard her say, "I really wish I could spend more time at work instead of with my children."  I hear the exact opposite quite often, though.

The people who installed the solar panels on my roof were all high school graduates or dropouts living paycheck to paycheck.  I think the sole person amongst them who had earned a college degree was their supervisor.  I guess if my goal was to exploit a bunch of working poor uneducated people, then I would make them all manual laborers installing solar panels and wind turbines for the rest of their lives so that wealthier Americans could afford to purchase the electricity that they could not.  In either case, all of those people operating the nuclear power plants continue to exist, with or without high paying STEM jobs that typically cause them to seek out college education so that they can learn about why protecting the environment is a useful goal, as well as the monetary wealth to educate their own children at a collegiate level.  I can't possibly fathom why we'd want more of that.

The US solar industry directly employs 250,000 people and solar supplies.  The pay scale can be every bit as high, but most of them, by numbers, who are installers, make between $30K and $40K per year, sometimes with benefits, which is nice, and very few of those people have college degrees, because they can't afford to go to college with $30K/yr salaries.  The US wind industry employs, I think, 100,000 to 110,000.  I'm almost certain that your next argument will be that wind and solar employ more people than nuclear, therefore it's better than nuclear due to the jobs created.  Those people are also consuming things and creating waste to transport and repair / refurbish / replace everything they install.

I don't want a future filled with barely-educated manual laborers who can scarcely afford to use the product or service that they produce.  Henry Ford had the correct model.  Nuclear power is the most efficient society-level pooling of labor, resources, and capital to produce the energy, the master resource, that technologically advanced human civilization requires, so that everyone can reap the benefits.

Lots of things are going to change in the future.

One of the changes will be that we will see solar panels on domestic properties installed by robots not humans, slashing the costs dramatically. In some ways that will be sad because solar panel installation has been a good source of jobs for less qualified but young and healthy people who enjoy outdoor work.   

Another change will be new build housing will have solar power tiles integrated into their roofs. Likewise when people re-roof this will become an increasingly attractive option.

With solar energy there are many, many possibilities. For instance,  I've floated (ha-ha) the idea of huge solar tankers heading to sunny latitudes and using huge "PV trawlers" to charge up 400,000 tons of chemical batteries, eventually collecting 100 GWhs. This would have the benefit of being able to serve large population centres at ports without need for long distance transmission. This might not be economic at the moment but it may become so if chemical battery costs continue to decline dramatically.

There's the possibility of commercial printed ultra-lightweight PV film.  This could be perfect for placing on roofs of industrial and warehouse buildings, again resolving many land use issues. This isn't a pipe dream as such film already exists for niche uses:

https://www.eni.com/en-IT/operations/or … c-opv.html

For me the future lies with solar and wind - with geothermal perhaps becoming increasingly important as well.

Last edited by louis (2021-03-11 15:58:10)


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#31 2021-03-11 18:04:39

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,361

Re: Hydrogen from Nuclear Fission Economy

tahanson43206,

Any product produced needs to be storable and the economic benefits associated with the derivative product must exceed the value of the nuclear fuel required to produce it.  Hydrogen isn't indefinitely storable and almost nothing runs on pure H2 in our society at this point in time because we stopped pursuing fuel cell technology in a serious way (a mistake, IMO), so it would be better to store the Hydrogen as a room temperature storable chemical, such as ammonia / propane / gasoline / diesel / kerosene.  Those have more energy-favorable synthesis processes associated with them than simple water electrolysis.  Even if we pursue AFCs and PEMFCs, then storing the Hydrogen as ammonia still makes far more sense to me, and once we produce something, we have to store or consume it.

A reactor sited near an ocean has a very healthy supply of H2O, CO2, Lithium, Magnesium, Sodium, Uranium, and Thorium available for the taking.  We can make a lot of the chemicals that our solar and wind evangelists prefer by collecting and refining those elements using power, process heat, and pressure provided by the reactor.  Additionally, manufacturing is not strictly limited to times when excess power happens to become available, as is the case with solar and wind power.

We have special "sponges", that require essentially no input power, capable of lapping up Uranium and Thorium, for example.  We could do the same thing to extract Sodium and Lithium to make batteries, but without the enormous human and environmental costs associated with using limited fresh water supplies in a desert, the way we do in South America.

Basically, I would like to use nuclear power to stockpile the chemicals and metals that humanity needs to generate energy or useful goods.  If we think a crash program to develop improved solar panels and wind turbines will work, then nuclear power can provide the energy to do that, until such time as we have durable or easily recyclable photovoltaics and wind turbines.  Alternatively, we could produce materials for more durable and permanent solar thermal power plants and much improve CNT fabrics for composites that can make wind turbine blades last 100 years, rather than 10 years.

I don't disagree with the underlying premise behind what our wind and solar evangelists want to ultimately do, even if most of them can't articulate what that is because they don't know enough about what they're talking around to pin down why wind and solar are our ultimate "forever" energy sources, I'm simply trying to point out to them that our present technology is too immature to do what they want to do, so we need to buy more time to improve it.  Idealists are very prone to fantasizing about idealized visions of what they think the future should look like, rather than what it will actually look like using what engineering can realistically achieve.

Anyway, the overriding point is that we use energy to recycle and stockpile, so we can decide what to build next after we work out the most long-term sustainable ways to do things.  We're already well past a tipping point where making the best choices about how to build things is of primary importance.

For example:

I claim and assert that the best way to make a light motor vehicle is to use the cheapest sheet steel available, advanced welding techniques to construct a relatively lightweight body / chassis using a heat-bonded honeycomb core to the steel panels, coat the thing with the cheapest paint we can buy, use a simple cast iron turbocharged in-line engine with a minimal number of different materials, take advantage of 3D printing and AI-optimized part design for particularly complex and heavy structural parts such as the suspension, and a simple utilitarian interior without a bunch of electronics and plastic crap, because no matter if the car is battery powered or combustion engine powered, they get relegated to the scrap heap in less than 10 years time, and often sooner than that.  Therefore, ease of assembly, dis-assembly, repair, and recyclability of energy-intensive raw materials are the figures of merit.

If we can reuse the engine and transmission because we design those to be truly durable, then we can pull the motor and drive train components from the old chassis, melt down the chassis to produce new sheet steel for the next chassis, refurbish the motor, add newer / better "electronic spices" to the computer control system for the engine and transmission, put it right back into the next motor vehicle, and we just saved all the energy associated with going from raw ore to finished motor vehicle while producing a "new car" that performs just as well as the old one did, if not better.

The only other long term viable alternative is making cars / appliances / homes as durable as is practical, but that depends upon the purchasing habits of the consumer.  They like buying cheap crap early and often (it's not a problem limited to the US, either, since the Europeans and Chinese and Indians are starting to exhibit the same purchasing habits as American consumers), but there's nothing ultimately "cheap" about making things you can't recycle, because there's a finite supply of all resources and making new materials requires a lot more energy than recycling the existing materials.

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#32 2021-03-11 18:53:02

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,361

Re: Hydrogen from Nuclear Fission Economy

Louis,

louis wrote:

In the UK we are currently seeing the demise of many high street shops as online shopping takes the place of physical shopping to a large degree. Now a retail economist will explain this by saying online shopping uses far fewer resources e.g. salaries for shop workers, floor space, staff facilities, heating and lighting etc etc. They don't say "Well human beings still have to live so we shouldn't take account of savings on servicing human beings." So not a poor or irrelevant argument at all. Nuclear power stations are consuming resources all the time, 24/7. If the staff car park needs re-tarmacing every ten years that is a valid material input to put into your calculation.

I have never heard of modern wind turbines needing major replacements as a matter of course during their 20 years advertised lifteimes. Think I would need some links. Perhaps it's been a design issue with a particular turbine. And by the way it's obvious lots of modern wind turbines are going to be operating way beyond their 20-25 year lifetimes. When they do, the cost of electricity they generate will plummet as with old LWRs which have paid back their initial investment. What's good for nuclear is good for wind. Once wind energy is a mature technology this is going to feed into lower costs across the board.

Well, now you can't claim ignorance about an actual problem that I expected you would already have an answer for:

Los Angeles Times - Wind turbine blades can’t be recycled, so they’re piling up in landfills

Here's a similar story from your own country's primary propaganda source:

What happens to all the old wind turbines?

At least we've discovered new ways to turn old wind turbine blades into rabbit turds so we can put more plastic into glue, paint, and concrete.  There's only one problem with that.  New rabbit turds are not equivalent to new wind turbine blades, which would be required to produce new wind turbines, that we'll then need to replace every 20 years, provided that they last that long in service.

The problem is that wind and solar are not getting any cheaper.  In point of fact, all forms of energy are getting more expensive, not less expensive, because the least expensive forms of energy are now more expensive, in terms of relative cost.  When electricity rates continually increase as more and more unreliable energy is dumped onto the grid, that's not a sign of costs going down, no matter what religious propaganda you've chosen to buy into.  Contrary to what you've been indoctrinated to believe, generating energy doesn't have to be a never-ending Chinese fire drill, which is what we'll be in for unless we solve the sustainability and durability problems with wind and solar.

louis wrote:

Lots of things are going to change in the future.

One of the changes will be that we will see solar panels on domestic properties installed by robots not humans, slashing the costs dramatically. In some ways that will be sad because solar panel installation has been a good source of jobs for less qualified but young and healthy people who enjoy outdoor work.   

Another change will be new build housing will have solar power tiles integrated into their roofs. Likewise when people re-roof this will become an increasingly attractive option.

With solar energy there are many, many possibilities. For instance,  I've floated (ha-ha) the idea of huge solar tankers heading to sunny latitudes and using huge "PV trawlers" to charge up 400,000 tons of chemical batteries, eventually collecting 100 GWhs. This would have the benefit of being able to serve large population centres at ports without need for long distance transmission. This might not be economic at the moment but it may become so if chemical battery costs continue to decline dramatically.

There's the possibility of commercial printed ultra-lightweight PV film.  This could be perfect for placing on roofs of industrial and warehouse buildings, again resolving many land use issues. This isn't a pipe dream as such film already exists for niche uses:

https://www.eni.com/en-IT/operations/or … c-opv.html

For me the future lies with solar and wind - with geothermal perhaps becoming increasingly important as well.

I already have solar panels on my property, as well as a pair of Tesla PowerWalls.  Nothing fundamentally changed.  I still have to get power from the gas generating station every single day of the year.  That's fine for us because we spent our money, not everyone else's money.

Thin film PV doesn't change the recycling problem at all, except by making it more difficult, so it doesn't change much at all.  All of these new technologies are akin to having a single bazooka and a dozen oncoming tanks to contend with.

In the future, I'm going to live on Mars with my own cyborg that talks to me, wears a Star Fleet uniform, and can sing and dance.  There's just one problem with that "glittering vision of tomorrow".  We're not there yet, nor anywhere close to "being there".

For me, the future lies with making better decisions about what to build, how to best use reliable energy sources that truly are "lowest cost" over time, rather than the next 10 years, what materials are easiest to recycle, and how to restrain the continual growth in consumption without killing poor people by denying them energy, which seems to be what the wind and solar evangelists intend to do without explicitly stating as much.

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#33 2021-03-11 19:18:17

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,361

Re: Hydrogen from Nuclear Fission Economy

Terraformer wrote:

Extraction of Uranium from seawater

Firstly, pumping the seawater to extract this uranium would need more energy than what could be produced with the recuperated uranium. Then if trying to use existing industrial flow rates, as for example on a nuclear power plant, it appears that the annual possible quantity remains very low. In fact huge quantities of water must be treated. To produce the annual world uranium consumption (around 65,000 tU), it would need at least to extract all uranium of 21013tonnes of seawater, the volume equivalent of the entire North Sea.

Note that *current* consumption is 65 kilotonnes of uranium. If we tried delivering european level per capita energy consumption to the present world population, we would require a tripling of our global energy budget, which nuclear provides a tenth at present.

All this is to say, switching to nuclear would buy us maybe a decade (a lot of the energy is wasted due to inefficiencies, but it's not orders of magnitude) before we burn through our resources, so the only way we're going nuclear any time soon is if we have a crash Manhattan project to develop breeder reactors and other such new types.

Absent the will for such a program - which needs an advanced, competent, and functional country to do it - we're going down.

Terraformer,

The seawater Uranium extraction technology doesn't pump anything.  A special type of floating sponge (nano-bentonite, aka "fancy kitty litter") is dragged through the water using tidal action.  The waves do all the pumping.  The technology I saw demonstrated didn't have any moving parts, so it's not consuming any energy to collect Uranium and Thorium.  We do have to expend energy to release the Uranium from the sponge.  In the demo the guy in the lab coat washed the Uranium ore out of the sponge using a garden hose.  We have to do that anyway since we need to refine the collected Uranium and Thorium into metal.  If we attached it to one of Louis' solar powered ships, then what would it matter if we did want to slowly drag it through the water to collect the Uranium faster?

Current Uranium consumption is the result of nearly zero fuel reprocessing and very little breeding.  The breeder reactors exist and they do work, but we're choosing not to use them.  The actual problem is that even though we've led our horse to water, it doesn't want to drink.  If we closed down the Uranium mines, there's still enough Uranium fuel sitting in Paducah, Kentucky, to supply 100% of the electricity demand in America for at least the next century, if not several centuries by using a more moderate mix of nuclear and other energy generating technologies.  My point was that we could supply 100% of our energy needs, not that we should.  With recycling, a single load of fuel in a reactor that recycles its fuel, is sufficient fuel to produce full rated output for 75 years.  There's no fuel shortage.  There never has been.  We've decided that we don't want to run fuel / coolant slurries to extract 100% of the original energy content and don't want to recycle fuel, because either option would cost more money and, more or less, put the Uranium mines out of business for the next century or three.

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#34 2021-03-11 20:10:31

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Hydrogen from Nuclear Fission Economy

Yes they are replacing the blades and turbines but the towers remain - this is after 25-30 years of operation. I expect we'll find turbines and blades from more modern wind turbines last even longer.

Sounds like the recycling issue is being addressed.

The PV film obviously far, far less waste.

Green energy is a realistic way forward. I think this guy is right about the future of solar energy:

https://rameznaam.com/2020/05/14/solars … heap-2020/

We need to crack the energy storage problem but if solar power can generate electricity at 1 cent per KwH, the money is automatically there to solve it.


kbd512 wrote:

Louis,

louis wrote:

In the UK we are currently seeing the demise of many high street shops as online shopping takes the place of physical shopping to a large degree. Now a retail economist will explain this by saying online shopping uses far fewer resources e.g. salaries for shop workers, floor space, staff facilities, heating and lighting etc etc. They don't say "Well human beings still have to live so we shouldn't take account of savings on servicing human beings." So not a poor or irrelevant argument at all. Nuclear power stations are consuming resources all the time, 24/7. If the staff car park needs re-tarmacing every ten years that is a valid material input to put into your calculation.

I have never heard of modern wind turbines needing major replacements as a matter of course during their 20 years advertised lifteimes. Think I would need some links. Perhaps it's been a design issue with a particular turbine. And by the way it's obvious lots of modern wind turbines are going to be operating way beyond their 20-25 year lifetimes. When they do, the cost of electricity they generate will plummet as with old LWRs which have paid back their initial investment. What's good for nuclear is good for wind. Once wind energy is a mature technology this is going to feed into lower costs across the board.

Well, now you can't claim ignorance about an actual problem that I expected you would already have an answer for:

Los Angeles Times - Wind turbine blades can’t be recycled, so they’re piling up in landfills

Here's a similar story from your own country's primary propaganda source:

What happens to all the old wind turbines?

At least we've discovered new ways to turn old wind turbine blades into rabbit turds so we can put more plastic into glue, paint, and concrete.  There's only one problem with that.  New rabbit turds are not equivalent to new wind turbine blades, which would be required to produce new wind turbines, that we'll then need to replace every 20 years, provided that they last that long in service.

The problem is that wind and solar are not getting any cheaper.  In point of fact, all forms of energy are getting more expensive, not less expensive, because the least expensive forms of energy are now more expensive, in terms of relative cost.  When electricity rates continually increase as more and more unreliable energy is dumped onto the grid, that's not a sign of costs going down, no matter what religious propaganda you've chosen to buy into.  Contrary to what you've been indoctrinated to believe, generating energy doesn't have to be a never-ending Chinese fire drill, which is what we'll be in for unless we solve the sustainability and durability problems with wind and solar.

louis wrote:

Lots of things are going to change in the future.

One of the changes will be that we will see solar panels on domestic properties installed by robots not humans, slashing the costs dramatically. In some ways that will be sad because solar panel installation has been a good source of jobs for less qualified but young and healthy people who enjoy outdoor work.   

Another change will be new build housing will have solar power tiles integrated into their roofs. Likewise when people re-roof this will become an increasingly attractive option.

With solar energy there are many, many possibilities. For instance,  I've floated (ha-ha) the idea of huge solar tankers heading to sunny latitudes and using huge "PV trawlers" to charge up 400,000 tons of chemical batteries, eventually collecting 100 GWhs. This would have the benefit of being able to serve large population centres at ports without need for long distance transmission. This might not be economic at the moment but it may become so if chemical battery costs continue to decline dramatically.

There's the possibility of commercial printed ultra-lightweight PV film.  This could be perfect for placing on roofs of industrial and warehouse buildings, again resolving many land use issues. This isn't a pipe dream as such film already exists for niche uses:

https://www.eni.com/en-IT/operations/or … c-opv.html

For me the future lies with solar and wind - with geothermal perhaps becoming increasingly important as well.

I already have solar panels on my property, as well as a pair of Tesla PowerWalls.  Nothing fundamentally changed.  I still have to get power from the gas generating station every single day of the year.  That's fine for us because we spent our money, not everyone else's money.

Thin film PV doesn't change the recycling problem at all, except by making it more difficult, so it doesn't change much at all.  All of these new technologies are akin to having a single bazooka and a dozen oncoming tanks to contend with.

In the future, I'm going to live on Mars with my own cyborg that talks to me, wears a Star Fleet uniform, and can sing and dance.  There's just one problem with that "glittering vision of tomorrow".  We're not there yet, nor anywhere close to "being there".

For me, the future lies with making better decisions about what to build, how to best use reliable energy sources that truly are "lowest cost" over time, rather than the next 10 years, what materials are easiest to recycle, and how to restrain the continual growth in consumption without killing poor people by denying them energy, which seems to be what the wind and solar evangelists intend to do without explicitly stating as much.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#35 2021-03-11 20:27:48

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Hydrogen from Nuclear Fission Economy

Those real directors of real nuclear power companies are really desperate - hence trying to buy into the green economy. They can see the writing on the wall. The price drops for solar, wind and battery storage all point in one direction and it's not a nuclear future. They can't even compete with gas.

tahanson43206 wrote:

For kbd512 .... enjoyed your Post #27 in reply to Louis ...

Regarding the proposition of this topic .... Hydrogen is the feedstock for all kinds of value added products.

It is ** not ** necessary to sell the hydrogen a nuclear plant produces to the open market, although if the price is right then go for it.

Instead, it seems to me that a single nuclear reactor, situated as most are next to a river or a lake or the ocean, can support a nearby community of high value secondary products that can be stored until needed (a) or (b) the price is right.

In any case, ** real ** Boards of Directors of ** real ** nuclear plants are making these decisions today under market pressure.

I'd like to see reports of such decisions (and their benefits to shareholders) eventually show up in this topic.

(th)


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#36 2021-03-11 20:36:46

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,361

Re: Hydrogen from Nuclear Fission Economy

louis wrote:

Yes they are replacing the blades and turbines but the towers remain - this is after 25-30 years of operation. I expect we'll find turbines and blades from more modern wind turbines last even longer.

Sounds like the recycling issue is being addressed.

Yeah, by either setting them on fire or mixing the plastic into concrete.  We need more Chlorine and Fluorine bearing compounds in the atmosphere or ground water like we need another hole in the head.

louis wrote:

The PV film obviously far, far less waste.

That's good, because the materials used are much harder to come by.  Eventually, the recycling problem needs to be addressed.

louis wrote:

Green energy is a realistic way forward. I think this guy is right about the future of solar energy:

https://rameznaam.com/2020/05/14/solars … heap-2020/

Apart from lasers transmitting over specific wavelengths, there's no such thing as "green energy", so "green energy" isn't "the way forward" to anywhere.  There's only energy that pollutes one way versus another.  Your favored energy sources produce orders of magnitude more toxic waste that remains toxic until the end of time or until human physiology is altered to remain unaffected by elements like Arsenic and Gallium, unlike most types of nuclear waste.

Incidentally, I read your article and observed the graphs use.  They don't show wind and solar prices falling forever.  In fact, all of the grapsh presented show prices being about as low as they can be, as of right now (a time when most people can't afford to put a solar roof on their home).

louis wrote:

We need to crack the energy storage problem but if solar power can generate electricity at 1 cent per KwH, the money is automatically there to solve it.

We're just ten years away from cracking the energy storage problem, and much like fusion, we always will be.

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#37 2021-03-11 20:44:22

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,361

Re: Hydrogen from Nuclear Fission Economy

louis wrote:

Those real directors of real nuclear power companies are really desperate - hence trying to buy into the green economy. They can see the writing on the wall. The price drops for solar, wind and battery storage all point in one direction and it's not a nuclear future. They can't even compete with gas.

Louis,

They probably are desperate to continue living in a technologically advanced human civilization, because there's no such thing as a 100% wind and solar powered civilization that's anything but energy-poor and in the dark half the time.

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#38 2021-03-11 22:11:20

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Hydrogen from Nuclear Fission Economy

This thing is hugeBB1bxtRp.img?h=488&w=799&m=6&q=60&o=f&l=f
1,600 megawatts of offshore wind electricity

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#39 2021-03-12 03:20:21

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,352

Re: Hydrogen from Nuclear Fission Economy

kbd512 wrote:

They probably are desperate to continue living in a technologically advanced human civilization, because there's no such thing as a 100% wind and solar powered civilization that's anything but energy-poor and in the dark half the time.

Indeed.  Unfortunately it would appear that politicians on both sides of the Atlantic do not.  In Britain, we have been building high temperature gas reactors since the 1970s.  We had an active fast breeder reactor programme throughout the 1970s and 80s.  By 1990, it was complete and ready for commercial development.  The entire programme was dumped, along with all of the research findings, by the then Tory government, who observed at the time that Britain's low cost natural gas reserves in the North Sea could generate electricity at a lower cost.  Fast forward to 2000 and the UKs North Sea gas production had peaked and by 2020, the country was heavily dependent on imported gas from Norway and LNG from the Middle East.  Electricity prices have risen continuously, the UK outside of London is one of the poorest regions in Europe and what little industry the country has left is itching for an excuse to leave the country.

Meanwhile politicians appear to be completely ignorant of the role that energy plays in the industrial economy.  To the extent that they take an interest at all, it is to satisfy ideological lobby groups.  Lack of technology has never been the root of our problem.  The problem is a political class that are wholly incompetent and unqualified.  They live in a detached world and appear blithely unaware of the economic crisis that they are stumbling into.

The Chinese on the other hand, have active fast breeder and high temperature reactor programmes.  And their nuclear build programme is running at full capacity, churning out new reactors every single year.  These people are planning for the future, knowing full well that their coal production faces geological limits.  All indicators suggest that they are going to be running the world 10 years from now.

Lack of technology has never been a problem in the western hemisphere.  The problem is that we are run by morons who don't appear to care about the future.  The latest piece of economic news from the US.
https://www.zerohedge.com/economics/so- … ollar-dies

I rest my case.  I think we can forget about colonisation of Mars.  Fully equipped with all of the tools needed to build a prosperous technological society, our elites are deliberately running us into the ground.

Last edited by Calliban (2021-03-12 03:30:20)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#40 2021-03-12 03:58:18

Terraformer
Member
From: Ceres
Registered: 2007-08-27
Posts: 3,800
Website

Re: Hydrogen from Nuclear Fission Economy

The problem is a political class that are wholly incompetent and unqualified.

Nothing laid this bare in the way last year did. I honestly don't think our Prime Minister has studied maths at all at any level since he was 16... and benefit cost analysis isn't something our political class is fond of. They're unsuited to run a parish, let alone a country that presumes to be a great power.


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#41 2021-03-12 06:01:47

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: Hydrogen from Nuclear Fission Economy

This topic is about production of hydrogen by nuclear fission power plants, as a way of increasing the economic value of the energy they are releasing from nuclear fuel.  While discussion of human failings is (probably) appropriate in this topic as it is in any topic, I'd like to see some of the "energy" created by the topic invested in finding evidence in support of the opening thesis ... that managers (Boards of Directors) of nuclear facilities are (finally) looking beyond the original idea of delivery of raw power, to the (potentially) much more lucrative production of high value products.

kbd512 recently gave a comprehensive overview of the potential of nuclear power for production of high value derivative products.  I'd like to see examples cited as they become available in the media or other sources. 

Thanks to all for helping to give this topic a running start!

(th)

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#42 2021-03-12 08:17:35

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,352

Re: Hydrogen from Nuclear Fission Economy

Nuclear reactors produce heat.  The product that they are built to produce is usually electricity, although in ships and submarines they are used to generate mechanical shafts power for propulsion.  The large LWRs presently in use, are not really suited for production of anything other than electricity as a primary product.  You could say that the electricity is stored in the products it is used to produce.

There has been discussion of using centralised heat sources for district heating in cities.  It is done in Scandinavia and Russia.  There is no reason why a small modular light water reactor could not be used to produce combined heat and power in this way.

Hydrogen production can take place using electrolysis, high-temperature electrolysis, or thermo-chemical water splitting.  In the first case, any source of electricity would work in principle.  The second concept involves using heat to provide part of the enthalpy change needed to split water in an electrolysis cell.  A high temperature nuclear reactor could therefore provide this heat directly, without prior conversion of heat into electricity.  The third process is thermochemical.  The most commonly cited process is the iodine-sulphur cycle, which requires temperatures greater than 800°C to be effective.

Steel production could make use of nuclear energy as well.  To produce steel using entirely nuclear energy, we would mix pieces of scrap steel with iron oxide and a flux within an electric furnace.  The mixture is then heated using a rotating electromagnetic field to the melting point of steel.  By passing hydrogen gas through the mixture, iron oxide is reduced into iron.  Small amounts of pure carbon can then be added to the mixture to produce carbon steel.

Ammonia production requires heat at about 500°C.  Again, this can be direct process heat from a high temperature nuclear reactor.  In fact, we could operate the process in steady flow mode by passing nitrogen through a gas cooled reactor and then into a steady flow chemical reactor.

Aluminium plants are typically located close to nuclear reactors or hydropower facilities.  It takes 20kWh of electric power to produce 1kg of aluminium.  A dedicated nuclear power plant is certainly a feasible option for aluminium production.

Brick making is a potential technical stretch option for high temperature reactors.  It requires temperatures in the region of 900-1100°C.  To achieve those sorts of temperatures, something other than steel is needed for fuel cladding.  Triso particles have been suggested.  Maybe stainless steel clad fuel, cooled by liquid metal would also be possible if fuel elements are vented and avoid building up internal pressure.

Biofuels could be produced from raw biomass using nuclear heat.  Chopped biomass could be dehydrated and subject to pyrolysis within an anaerobic furnace, using nuclear process heat with temperatures of around 500°C.  Vapours driven off of the furnace would be things like formaldehyde, methanol, methane and hydrogen.  All things that can be used as gaseous or liquid fuels.  A charcoal like solid residue would remain after heating.  This could be reacted with hydrogen to produce alkane or used as a coke substitute in steel manufacturing.  The ash would be returned to the fields as fertiliser.

There a probably more examples that I can't even think off.  Wherever large amounts of heat are needed, a nuclear reactor is a possible supplier of that heat.  On Mars, we could use high temperature reactors to provide heat for splitting CO2 into CO and O2.  Likewise, thermochemical water splitting to produce hydrogen and oxygen for fuel and metal production.  Small light water reactors mounted on trailers, would be useful tools for water mining.  You pump steam into the ground under pressure and then drill wells into the surrounding ice.  Water rises through the wells, driven up by a combination of steam pressure and static pressure of the overbearing rock.

Last edited by Calliban (2021-03-12 08:56:12)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#43 2021-03-12 08:54:22

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Hydrogen from Nuclear Fission Economy

106 metre blades.

Not sure where you get the 1,600 MW figure from - it's 14 MW capacity. Annual elecriticity production is more than enough to power the whole of the UK for one hour! 

https://www.ge.com/renewableenergy/wind … re-turbine



Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#44 2021-03-13 09:47:21

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Hydrogen from Nuclear Fission Economy

The wind is an issue for like you made note of blade sweep to wind speed and not all wind levels are applicable to a fixed size unit so its optimized for consistent levels of wind speed. Once its drops to low or are to high the blades are locked in place and no power is generated.

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#45 2021-03-13 10:14:47

Terraformer
Member
From: Ceres
Registered: 2007-08-27
Posts: 3,800
Website

Re: Hydrogen from Nuclear Fission Economy

The impression I'm getting is that breeder reactors are basically the highest technology readiness level option we have for maintaining our current energy levels. The dominant nuclear reactors designs aren't an option, because we hit peak uranium within a decade or so. Batteries are not there yet (Lithium-Ion is not an option to power the entire world, because don't have enough Lithium to provide even a single day of power storage at european consumption levels; we need Sodium-Ion for that).

My worry is that we'll fall into the energy trap - that by the time we acknowledge the need to construct large numbers of breeder reactors, energy scarcity will make them difficult to build. Related to this is the lead time to design and built plants, as well as the need to train people to work on and in them. The best time was two decades ago, the second best time is now, and all that. Non-breeder reactors should not be permitted.


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#46 2021-03-13 10:40:01

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Hydrogen from Nuclear Fission Economy

The battery technology is also dependent on the metals of the formula as the density of them are still increasing for some of the competing types.

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#47 2021-03-13 11:00:25

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,361

Re: Hydrogen from Nuclear Fission Economy

Terraformer,

If we already know that we can't produce enough Lithium-ion batteries to store enough power, and Sodium-ion batteries are still experimental technology, then the only remaining energy stores that can scale up to the level required are liquid hydrocarbon fuels made from recycled CO2 and H2O.  That means we're not going to stop burning liquid hydrocarbons.  The entire stated purpose of the wind and solar was to stop burning hydrocarbon fuels, so even with wind and solar, we're every bit as "stuck" in that energy trap.

Throughout all human history, we did not grow technologically by moving down the energy density ladder.  We went from wind (mechanical power for pumping water, grinding grains, etc) and solar (farming crops), to coal (mass producing concrete and steel), to oil and gas (larger and/or more efficient combustion engines, producing less pollution than coal, and capable of powering a variety of useful machines such as farming equipment / cars / trucks / buses / ships), to nuclear (the highest energy density fuel used to date, with the least quantity of waste generated), and now we're trying to go back to wind and solar, albeit with improved efficiency of the collection devices, which still doesn't address the intermittency issues with using those devices.

Unless the answer is to go up the energy density and efficiency pyramid, not down, then technologically advanced human civilization will regress, people will die, and our technological progress will stall for lack of energy.  SpaceNut has pointed out how numerous efficiency increases have not caused total demand for energy to go down.  There are quite a few examples of the opposite effect, which means a civilization with ever-increasing energy requirements needs more dense, rather than dilute, energy sources, if the goal is to continue technological progress and improved quality of life for more and more of our population.  I don't see any way around that problem.

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#48 2021-03-13 11:38:32

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: Hydrogen from Nuclear Fission Economy

For kbd512 .... on the chance you haven't seen Noah's application, please review his answer to your question for membership in the forum.

Thanks!

And thanks for keeping ** this ** topic moving!
 
For Terraformer ... thanks for your contribution to this topic!  Please keep a watch for articles or announcements about the theme, which is decisions of Boards of Directors of nuclear sites to manufacture hydrogen as feedstock for high value products.

Vertical integration should provide organizations who are managing nuclear facilities a way to sustain them over the longer term.

(th)

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#49 2021-03-14 20:55:25

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: Hydrogen from Nuclear Fission Economy

Here is an OilPrice report on the favorable trends toward a successful Hydrogen Economy ...

I'm dropping it into ** this ** topic because Hydrogen is the focus of the topic, although nuclear power is not mentioned in the OilPrice article.

https://www.yahoo.com/finance/news/way- … 00674.html

Editor OilPrice.com
Sun, March 14, 2021, 5:00 PM
After decades of stagnation and multiple false dawns, the hydrogen economy is now ready for prime time.  Investments in hydrogen technologies have skyrocketed over the past two years, with hydrogen being touted as the 'fuel of the future.' Meanwhile, industry experts predict that hydrogen could become a globally traded energy source, just like oil and gas, while Bank of America says the industry is at a tipping point and set to explode into an $11 trillion marketplace.
<snip>
The push to take hydrogen costs below $2/kg is, therefore, a potential game-changer for the entire hydrogen ecosystem because it could mean that, for the first time ever, hydrogen becomes cheaper than gas.

In fact, a recent analysis by the Hydrogen Council suggests that $2/kg as the tipping point required to make green hydrogen and its derivative fuels competitive in power generation, steel and fertilizer production, and long-range shipping. Green ammonia, which is made from green hydrogen, and being tested in the marine industry and also as a possible replacement for fossil fuels in thermal power generation. Compared to its grey brethren, green ammonia produces zero carbon when burned; boasts an energy density 80% higher than hydrogen, and is much safer than hydrogen.

The icing on the cake: the consortium of green hydrogen producers says we can expect to see $2/kg hydrogen in just four years' time.

"From an industry perspective, we see no technical barriers to achieving this, so it's time to get on with the virtuous cycle of cost reduction through scale up. Having led the race to deliver photovoltaic energy at well-below US$2 cents per kilowatt-hour, in certain geographies, we believe the collective ingenuity and entrepreneurship of the private sector can deliver green hydrogen at less than US$2 per kilogram within four years,"" Paddy Padmanathan, CEO of ACWA Power, has declared.

(th)

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#50 2021-03-15 07:41:06

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,352

Re: Hydrogen from Nuclear Fission Economy

I would propose a modular lead-cooled fast reactor as the best heat source for hydrogen and electricity production. Lead melts at 327°C and does not boil until 1749°C and does not react violently with water, air or CO2. Simple, single wall heat exchangers can be used to transfer heat to a secondary steam or SCO2 power generation loop.

There are other strong advantages to using lead as a coolant, compared to sodium, NaK, molten salt or gases. Because lead is a high Z material, it introduces very little moderation into the core, whilst retaining the excellent heat transfer properties of a metallic coolant. The high thermal conductivity of lead means that there is only a small temperature gradient between the fuel and the coolant. This allows the use of metallic Pu-U-Zr alloy fuel even at coolant temperatures of 600°C. The combination of metallic fuel and lead coolant result in an extremely hard neutron spectrum, which is very advantageous in a fast reactor.

1. At neutron energy greater than 1MeV, 238U will fast-fission without any requirement for breeding into 239Pu. Neutrons are born with an average energy of 2MeV. With very little moderation in the core and with heavy actinides dominating the number density of atoms in the core, direct fast-fission of 238U would represent a large proportion of total fission events. This is something that contributes negligible energy in a thermal spectrum reactor and very little even in an optimised sodium cooled breeder reactor. This reduces the required enrichment of Pu239 and substantially increases breeding ratio.

2. The number of neutrons yielded by any fission event, increases as incident neutron energy increases. So a harder neutron spectrum allows lower plutonium enrichment and a smaller critical core. There are also advantages in terms of breeding ratio, as there are more excess neutrons available to leak into blankets.

3. A hard neutron spectrum would allow the reactor to function as a travelling wave, breeding its own fuel as it operates. As the core leaks neutrons into surrounding depleted uranium blankets, breeding of plutonium occurs. The very hard neutron spectrum of this reactor type, allows the fission zone to gradually migrate into radial and axial blankets, without removing the materials for reprocessing. A small fissile starter core can therefore breed the fuel needed for decades of operation without the need to remove fuel for reprocessing. This saves a great deal of cost, as it allows an initial small amount of plutonium to gradually convert a much larger volume of depleted uranium into fissile fuel. Such a reactor could operate for decades without the need to shut down for refuelling. That is a huge economic advantage, as the only time the reactor would need defuelling and reprocessing, would be at the end of a 20-40 year life. The core would contain at least twice as much plutonium as it started with, allowing reactor capacity to rapidly increase between generations.

4. With a hard neutron spectrum, this type of reactor would fission actinide wastes that would not usually be considered useful as fuel materials. Actinides like Neptunium, Americium, Plutonium-240, Curium, etc, are non-fissile in LWRs, but most isotopes would fission in the very hard spectrum of the lead cooled, metallic fuel reactor. This reactor type can therefore take advantage of actinide nuclear waste streams as fuel. With successive generations of lead cooled reactors, the fuel cycle can be fully closed and long-term nuclear waste limited to fission products with half-lives no more than a few decades. That greatly simplifies radioactive waste disposal.

5. Lead coolant surrounding the core is an excellent neutron reflector. Lead cooled reactors can therefore be extremely compact. Combined with the high power density that liquid metal cooling allows, it should be possible to build reactors capable of generating 1000MW of heat, with a core diameter of just 1.5m and reactor vessel diameter ~2.5m. This allows the reactor to be shipped as a single modular component on a railway trailer or even by truck. This combined the economy of scale advantages of series factory production, with economy of size for a relatively high power core.

An operating temperature of 600°C would allow the reactor to provide process heat for both high temperature electrolysis and also ammonia production. Combined with an SCO2 power generation cycle, the thermal efficiency for electricity production would be ~50%. One disadvantage to the hard spectrum of this reactor would be the requirement for high worth control rods to achieve reactivity control. For small cores with high leakage, one alternative to control rods would be to control reactivity by reducing the amount of reflection into the core. This could be done using hollow steel rods, which displace the liquid lead reflector as they are are inserted.


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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