New Material Could Up Efficiency of Concentrated Solar Power (arstechnica.com) 80
An anonymous reader shares new work that could allow us to generate electricity using supercritical carbon dioxide. Ars Technica reports: The researchers involved in the new work, a large U.S.-based collaboration, focus on a composite material: tungsten and zirconium carbide. These have extremely high melting points: 3,700K for both materials. Both of them conduct heat extremely well, and neither of them expands or softens much under these conditions, meaning they would hold up better to the mechanical stresses. While the stats are impressive, the amazing part of this is how the material is fabricated. The researchers started with tungsten carbide, a ceramic that can be formed into a porous material simply by pouring it as a powder into a mold and heating it. At this point, the ceramic can be further machined to produce a final shape. Once in its final form, the ceramic was placed in a bath of a molten mixture of copper and zirconium. The molten mixture filled the pores, and the zirconium reacted with the tungsten carbide, replacing the tungsten. The copper in the molten material formed a thin film on the surface of the solid.
The tungsten then filled the pores in the resulting material, allowing it to retain the same shape and size despite the chemical changes. The zircon carbide ends up providing the material with a stiffness even at high temperatures, while the tungsten is flexible enough to keep the whole thing from being brittle. And the whole thing conducted heat better than the metals currently in use. The remaining issue is that, at the conditions involved in solar thermal plants, the copper on the material would react with the carbon dioxide, forming a copper oxide and releasing carbon monoxide. But the researchers determined that adding a small amount of carbon monoxide to the supercritical CO2 would suppress this reaction, something that they confirmed experimentally. Because the material holds up to these conditions so much better than the metals currently in use, it's possible to use much less of it to build a heat exchanger. This is great economically (since you need fewer raw materials), and the small size increases the power density and efficiency of the heat exchanger.
The tungsten then filled the pores in the resulting material, allowing it to retain the same shape and size despite the chemical changes. The zircon carbide ends up providing the material with a stiffness even at high temperatures, while the tungsten is flexible enough to keep the whole thing from being brittle. And the whole thing conducted heat better than the metals currently in use. The remaining issue is that, at the conditions involved in solar thermal plants, the copper on the material would react with the carbon dioxide, forming a copper oxide and releasing carbon monoxide. But the researchers determined that adding a small amount of carbon monoxide to the supercritical CO2 would suppress this reaction, something that they confirmed experimentally. Because the material holds up to these conditions so much better than the metals currently in use, it's possible to use much less of it to build a heat exchanger. This is great economically (since you need fewer raw materials), and the small size increases the power density and efficiency of the heat exchanger.
Then what (Score:2)
With this stuff you could make a really hot solar oven.
But what are you going to cook in it?
Re:Then what (Score:4, Interesting)
Solar-thermal is dying and this material is unlikely to revive it. Solar PV has dramatically declined in price, and is likely to continue to do so as manufacturing improves. Solar-thermal isn't cost competitive, and has far less room for improvement, since mirrors and pipes are mature tech. Solar-thermal requires more maintenance, and requires direct sun. Unlike PV, it will produce no power on overcast days.
The only significant advantage of solar-thermal is that it can store heat and time-shift power generation. But that is not enough of an advantage to offset the higher costs.
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> The only significant advantage of solar-thermal is that it can store heat and time-shift power generation
That's a pretty useful "advantage".
you made the argument (Score:2)
Solar thermal it works in the DARK! (Efficiency isn't always about $.)
baseline power.
I don't think battery + PV costs + land have costs have caught up. I would think thermal gets more power for the land area. Why can't they generate power during overcast days? Concentrating thermal towers should still have some output...not parabolic troughs. I would think that improvements on IR light are still possible since a lot of that goes thru clouds.
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Solar thermal it works in the DARK! (Efficiency isn't always about $.)
Power prices are higher during the day than at night. So cutting back on valuable power to make more cheap power isn't a good business strategy.
Also, building a storage tank that can hold billions of watt-hours of superheated steam isn't free.
Why can't they generate power during overcast days?
Because mirrors can't concentrate diffuse light.
I would think that improvements on IR light are still possible since a lot of that goes thru clouds.
IR does not go through clouds.
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Also, building a storage tank that can hold billions of watt-hours of superheated steam isn't free. ...
That is exactly why you don't store steam, but molten salts
IR does not go through clouds. :D
It does. But it has the same problem with "diffuse light"
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Think about it - it is NOT as bas as you think (Score:2)
Correction: prices TODAY are higher during the day. With increased solar driving down daytime demand those prices will drop and with enough solar the sunny daytime prices will become the lowest price; while the night and overcast days will raise prices. DEMAND is not the only factor setting rates and nothing says in the future it has to be as much of a factor or at all. Think ahead.
Massive energy storage is horrible for electricity. For heat, is very efficient. They don't store heat as steam, duh!! Hea
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You can use thermal storage for PV generated electricity, the round trip efficiency is pretty dire but if the electricity cost is low enough it doesn't really matter.
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Solar-thermal is dying and this material is unlikely to revive it.
No it is not.
It is actually the future of solar power. They have reservoirs build in and work up to 4 days without sunlight, and they are dispatchable.
But that is not enough of an advantage to offset the higher costs.
Seems the power plant companies disagree.
You forget that the typical mirror based plants are not the only ones, e.g. we have up wind plants, too. They are simple and cheap.
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Solar-thermal is dying and this material is unlikely to revive it.
I think this will come in pretty handy for the molten salt solar.
Solar PV has dramatically declined in price, and is likely to continue to do so as manufacturing improves.
That doesn't mean that the two compete. PV appears to be in the peak power market during the day and molten solar at night when people are home.
Solar-thermal requires more maintenance, and requires direct sun.
Yes. It is solar power.
Solar-thermal isn't cost competitive, and has far less room for improvement, since mirrors and pipes are mature tech.
Isn't cost competitive with what?
The plants produce four times the energy when you double their size there are plenty of place you could put these in deserts.
Unlike PV, it will produce no power on overcast days.
That's why we need to build huge amounts of them in different places. The sun is always shining somewhere. That's a
Re:Then what (Score:4, Interesting)
With this stuff you could make a really hot solar oven.
But what are you going to cook in it?
Carbon dioxide. It says so in the article.
My guess though is that they'll "cook" salts, melt some salts to the point they flow like water and they make very nice heat transfer materials for running brayton cycle turbines. These turbines can react quickly to changing power output demands, are quite small for the power output compared to other heat engines, and the salt works well for thermal storage over many hours if kept in a proper storage tank. All good stuff for replacing natural gas and oil to make electricity.
Another application I can think of is to make hydrogen from the water for synthesizing fuels and fertilizers, as well as make some desalinated water as a byproduct for use in municipal water supplies.
Also in the article is the potential use in making better natural gas and nuclear power plants. This is good stuff for energy production, finding something to "cook" is the least of the problems.
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Also in the article is the potential use in making better natural gas and nuclear power plants.
Also, as more and more nuclear reactors are retired converting them to natural gas as their turbine and grid infrastructure is already built. That's a huge amount of embedded energy invested in concrete and construction logistics building that infrastructure. There is a huge opportunity for climate wins by re-using this infrastructure and converting it to natural gas.
Plus operators or former nuclear plant can still generate profit on sites where they store nuclear material. You may even be in a positi
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Nuclear power is the safest and lowest CO2 producing energy source we have.
Uh, no. Solar, Wind, Hydro and geothermal are all lower than Nuclear. You can check Low-carbon Power [wikipedia.org] which does list Nuclear above solar, however it references the Vatenfall literature which has significant problems with its method.
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Also on CMO you will see nuclear is safer than solar, safer than everything really, and uses comparatively little material resources per energy produced.
You don't have all the facts and refuse any given to you. [stormsmith.nl] Therefore your statements don't have any credibility.
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From your source I find this:
Under the current conditions the specific CO2 emission of nuclear power is roughly 80-130 gram CO2/kWh.
https://www.stormsmith.nl/i05.... [stormsmith.nl]
Compare that to the CO2 emissions from here: http://cmo-ripu.blogspot.com/2... [blogspot.com]
While the source you gave shows more CO2 from nuclear then from Dr. Malhotra it still shows nuclear power having lower CO2 emissions than hydro and solar, about on par with biomass, and less than double that of the very low CO2 from wind. Dr. Malhotra shows data with nuclear lower than all the above but your source doesn't change the primary point I make, that nuclear
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This material's strength at high temperatures allow it to be used as the "boiler" for a solar steam turbine.
For a boiler like this you want the material as thin as possible to allow heat to flow through it rapidly, but it also needs to withstand an internal pressure of many atmospheres*. You also don't want it to melt through and fail if there is an interruption of flow in the heat transfer liquid.
*73 atmospheres for CO2, 225 atmospheres for water.
As an aside, it could also be used for the hot end of a Sti
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Sounds like the mother of all papers. (Score:1)
http://www.x-mol.com/paper/857... [x-mol.com]
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So what is this stuff? Is it an alloy, a ceramic or some sort of composite?
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You could be right. IIRC Tungsten is relatively expensive and quite difficult to work (though they aren't dealing with metallic Tungsten).
But you could also be quite wrong.
OTOH, do note that the proposed application is heat exchangers. These aren't only used in solar power plants, and aren't used at all in photo-voltaic systems. So the title is misleading, and the application is as likely to be nuclear plants as solar plants.
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the application is as likely to be nuclear plants as solar plants.
You would have to account for what neutron bombardment in nuclear plants would do to this material before it could be used there.
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No. The heat exchangers aren't usually near the core of the reactor, so only get relatively low levels of radiation.
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No. The heat exchangers aren't usually near the core of the reactor, so only get relatively low levels of radiation.
Indeed. I was considering it from the perspective of the cladding around the fuel rods. I'm uncertain if it would have much of an impact between the primary and secondary cooling loops in a PWR as you have mentioned.
As for a molten salt reactor, the salt would carry the isotope around so in that situation the heat exchanger would be exposed. I should have mentioned those scenarios when I posted - thanks for the opportunity to clear that up.
Much wider applications!! (Score:1)
This has much more applications than simply solar: Jet turbine blades, valves, piston and cylinder head coating for internal combustion engines. If this has the same tensile strength as Inconel at 3 times the temperature we can have 64% efficient engines.
This is a problem? (Score:2)
One problem here is that both natural gas and nuclear plants also rely on heat exchangers, and there's no reason this material can't be used to boost their efficiency, too.
I don't see a problem here.
In fact such materials with such varied uses should be seen as a very good thing. Right now solar is the new pink... or something. Solar is fashionable. Solar power is getting a lot of backing right now from government funding, private funding, and just general popularity. With that there is leverage to divert some of that funding to this materials research. If they can get the people in natural gas and nuclear convinced it will help them too then they can secure more funding
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One problem here is that both natural gas and nuclear plants also rely on heat exchangers, and there's no reason this material can't be used to boost their efficiency, too.
I don't see a problem here.
In fact such materials with such varied uses should be seen as a very good thing. Right now solar is the new pink... or something. Solar is fashionable. Solar power is getting a lot of backing right now from government funding, private funding, and just general popularity. With that there is leverage to divert some of that funding to this materials research. If they can get the people in natural gas and nuclear convinced it will help them too then they can secure more funding.
Solar is in the news a lot because it's easy to implement on a personal scale. I think that you'll see a lot more articles over the next 5 to 10 years concerning the development of tidal and wave powered generators. These would be particularly beneficial in North-East US/Canada where NIMBY is stalling the installation/expansion of offshore wind farms.
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Solar is in the news a lot because it's easy to implement on a personal scale.
Maybe I'm nit picking here but this is not the kind of solar that can be implemented on a personal scale. This new material is only helpful on solar thermal systems, and not the kind used for household water heaters either.
I think that you'll see a lot more articles over the next 5 to 10 years concerning the development of tidal and wave powered generators. These would be particularly beneficial in North-East US/Canada where NIMBY is stalling the installation/expansion of offshore wind farms.
Tidal and wave power have problems with silt in the water causing incredible wear on systems. If it's not the technical problems that sink tidal and wave power then it will be a different kind of NIMBY that don't want to see fish habitats getting disturbed or something.
Another thing is
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Tidal and wave power have problems with silt in the water causing incredible wear on systems.
Strange that neither the power plants nor the power plant operators know that.
Tidal, wave, solar, and whatever else they are working on, won't come to market for at least a decade.
Well, if you start building a nuclear power plant now, I guess it will be online in 20 years.
Wave power plants work like wind plants. You can put one online every few days ...
And I don't get what you mean with "market" ... you can buy the
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Another thing is that if global warming is a problem that needs a solution RIGHT NOW then we need nuclear power.
I think the main problem with your argument is that you don't have all the facts and refuse any given to you. Therefore your statements don't have any credibility.
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I believe the main problem with your argument is that you are a poopy-head. If you just want to bring the level of your debate to name calling then I'll reciprocate. Just because you are using multisyllabic verbiage to make your ad hominem doesn't mean it's any more valid as an argument.
You don't have all the facts and refuse any given to you. Therefore your statements don't have any credibility.
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Still not an argument.
Use a pseudonym if you want to have an argument.
Problem solved!! (Score:1)
Get over your love of nuclear power. It is a shit bird. Leave solar be, it will save us.
That's good to hear. So, now everyone will shut up about global warming then? If solar will save us then the problem is solved. Yep, all problems on global warming are solved. The debate is over. No need to bring up global warming again. I will never ever have to hear about global warming again, because solar power has solved the problem.
Everyone hear that? We've solved the global warming problem. So, don't bring it up ever again.
If someone does bring it up again then I will bring up nuclear power a
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How about we drop all the funding for shills, stop all the government subsidies, and let the open market pick a winner?
As Nuclear power is the only thing benefiting from this, it sounds like a great idea. Solar and Wind will continue to improve and investments in Nuclear power will seem like the insanity that they are.
Humanity made a big mistake choosing Uranium over Thorium and now we can't go back because of the spent fuel we have lying around.
Future investments in Nuclear will come in the form of solar and wind powered accelerators that destroy the spent fuel. It's a shame all of the nuclear advocates here couldn't g
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https://articles.thmsr.nl/the-flibe-energy-lftr49-the-triple-ace-in-nuclear-gen-iv-design-ea9bffcd71dd
I've read this before. You don't have all the facts and refuse any given to you. Therefore your statements don't have any credibility.
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Yep, PROBLEM SOLVED! Therefore I should never have to hear of global warming ever again. We solved all our global warming problems with natural gas and solar power.
PROBLEM SOLVED!
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One problem here is that both natural gas and nuclear plants also rely on heat exchangers, and there's no reason this material can't be used to boost their efficiency, too.
I don't see a problem here.
The material would have to be tested for how it behaves under Neutron bombardment.. That's the thing that limits the life of all nuclear reactors to a few decades. The older they get the more brittle the reactor vessel becomes and the more likely they will have a Loss Of Cooling Accident or LOCA. That the reason a lot of utilities opt to shut them down early.
Solar is fashionable.
The sun is always stylish, I've noticed it's always so radiant.
Solar power is getting a lot of backing right now from government funding, private funding, and just general popularity.
Not according to the 2005 US Energy Act. Solar can't access any funding through it
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If we take what we have today and just build more of the same then we will know that nuclear will continue to be safe, low CO2, and reliable.
As you are not in possession of all of the facts it is clear that your statements have no credibility.
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What facts am I missing?
Use your pseudonym if you want to discuss it.
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Come on, "allow us to generate electricity using supercritical carbon dioxide"? That's the most ridiculous clickbait I've seen recently. Makes it sound like some kind of free energy scam. The CO2 is just part of the process of making an advanced alloy that might be useful in a heat exchanger. Come on slashdot, this is way over the top.
Wrong. TFA says that the higher operating temperature enables them to use supercritical CO2 instead of steam as the working gas for power generation.
It would be funny ... (Score:4, Funny)
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supercritical co2 just means normal co2 under very high pressures. It is the best way known to move heat from one place to another for a long list of reasons including: it absorbs heat very quickly, it has high heat capacity, it moves like a liquid, it can be easily pumped, and can be forced to quickly give up/release heat (by lowering pressure), it has a relatively low operating pressure/temp compared to other gas supercritical points, and finally it is just harmless, abundant, non-corrosive, non-toxic co2
It would be funny ...R-744. (Score:3)
Sounds like a replacement for Freon.
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and indeed it is. The reason I suspect it isn't more popular is that 1500+ psi valves/etc. tend to cost about 10x as much as their 200-300psi counterparts.
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They’ve upped the ante; deal with it.
hypersonic applications? (Score:1)
I'm sure someone already thought of this but (3700K 273.15) × 9/5 + 32 = 6200.33F --> maybe this stuff could be used on hypersonic aircraft or spacecraft heat shields.
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Back in the early 1980s, I had an exam exercise to work out whether aluminium or c
Fun fact (Score:3)
Lazy authors (Score:2)
Here we've got this new composite material that's a superb thermal conductor at high temperatures. No, we can't be bothered to tell you what the thermal conductivity is.
Read the Nature article and the best they can do is say it's 2 to 3 times better than existing materials, iron and nickel. That means its thermal conductivity is somewhere near 220 (metric units). Copper is about 400, so we're not going to be using this stuff in computer heat sinks.
Perhaps good for 3D printing? (Score:2)