Making Liquid Fuels From Sun and Air 163
GregLaden writes: There is promising research on converting atmospheric CO2 and water, using sunlight as a source of energy, into burnable liquid fuels. This is not a carbon capture technique because the CO2 ultimately returns to the atmosphere after burning the fuel, but it could allow the production of enough liquid fuel to allow the rest of the motorized economy to switch to mainly electric. There are key uses for liquid fuels, even if most 'engines' become electric motors. The science of how this works is fairly interesting, and a recent writeup in Science gives some of the details.
Renewable Energy is a better label (Score:4, Insightful)
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The phrase you're looking for is "carbon neutral."
Anyway, this is not a revolutionary concept. It's fundamentally no different than making ethanol or biodiesel, except that you're using a machine instead of a plant to do it.
Photons and solar wind (Score:5, Informative)
Since E=Mc^2 the whole earth gets 1.9 kg/s of sun's mass in the form of ultra-violet, and visible photons. But the earth recycles these photons to longer wavelengths and radiates slightly more mass/s in the form of infrared photons (the excess comes from the heat generated by radioactivity in rocks).
In addition the sun sends matter to Earth in the form of solar wind, mostly protons and electrons and a few helium nuclei send by the solar atmosphere. The average direct mass flux for the whole earth amounts to about 0.75 kg/s.
One could also think about the sun neutrino flux but most of these particles traverse the earth without stopping.
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That's a bit misleading, although technically correct in the center of momentum frame. In general the relativistic energy is obtained from the length of the 4-momentum m(vx, vy, vz, mc^2) which gives the oft-quoted E=mc^2 for a mass that has no motion relative to the observer. But for a massless particle (which according to the theory must move at the speed of light in every frame), E=Pc .
So more accurately the Sun loses mass to produce light but the transfer to Earth involves only energy and momentum. Ab
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You don't need to care how the energy is transfered from the sun to the earth, just that it is conserved.
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I don't know about theoretical, wasn't someone making biodiesel on an algae farm a while ago? Wonder what happened to that?
Re:Renewable Energy is a better label (Score:4, Informative)
asked then answered: it's a commercially viable option already: http://cleantechnica.com/2014/... [cleantechnica.com]
Re:Renewable Energy is a better label (Score:4, Informative)
"Converting water into Oxygen and Hydrogen SPENDS the water, not renew it."
True, but burning said hydrogen CREATES water.
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shhhhhh. he was on a roll. let him expound on the idea that combusting hydrogen destroys matter.
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i wouldn't worry about it, we're losing plenty of mass, and gaining plenty of mass too.
http://www.bbc.com/news/magazi... [bbc.com]
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well the question there is, are you worried about you, worried about your descendants or worried about the human race in total.
for the first two, no, nothing to worry about, for the last, almost certainly nothing to worry about.
We're barely changing carbon dioxide, 2ppm per year out of a total of running total of about 400 ppm CO2.
and we've been like, super dedicated to that. I don't imagine we'll make much of an impact on hydrogen loss by the time we move on to something better.
also, you underestimate how
It isn't a carbon capture technique? (Score:4, Interesting)
This is not a carbon capture technique
Wait, you can't use it to extract "Fuel" and then pump it back into the ground where the oil used to be?
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Wait, you can't use it to extract "Fuel" and then pump it back into the ground where the oil used to be?
You could do that ... but that would be dumb. Once you extract the CO2 from the atmosphere, you can just pump it directly into the ground, rather than expending a huge amount of energy to convert it to a hydrocarbon first. Any geologic formation that held methane, should have no problem holding CO2, so any depleted shale bed should work fine.
Another option would be to use the CO2 to enhance oil or gas recovery. Pump the CO2 down, and it can mobilize and displace the hydrocarbons, and make them easier to
Re:It isn't a carbon capture technique? (Score:5, Informative)
Here in Iceland they're even doing CO2 injection at the Hellisheiði geothermal power plant. It does indeed seem to work - although it doesn't come free, of course
Fuel from CO2 and renewable energy is a great example of why it's irrelevant whether liquid fuels are produced in an "energy positive" manner like the "peak oil" crowd obsesses over. Liquid fuels don't need to be energy positive, just human society as a whole. Liquid fuels are actually a very expensive form of energy per joule compared to most other widespread forms of energy that we use. It can make perfect economic sense to produce them in an energy-negative manner using other, cheaper forms of energy as the source; all that matters is that when all forms of energy combined are considered, that the energy outputs outweigh the energy inputs to produce that energy (preferably by a large margin).
Of course, it's probably going to be a while before fuel from CO2 is the cheapest way to get it. You can make liquid fuels from syngas (CO + H2), which can be made by the incomplete combustion of almost any organic matter, from coal to trash. I'd think it'd be hard for these CO2/sunlight fuels to compete with that.
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Note: When writing the above, I initially wrote "... like the "peak oil" crow obsesses over." While I corrected it, come to think of it, wouldn't that make a great mascot for peak oil? A glossy-black animal that feeds on the remains of the living and has often been seen as an omen of death?
Where's John Oliver when you need him? ;)
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Hellisheiði - I actually rubbed my monitor thinking there was some crud obscuring the text...
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when you got that many vowels in a row, you're in for some foreign language fun.
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when you got that many vowels in a row, you're in for some foreign language fun.
Foreign language speakers make similar comments about consonants in English. My wife is Chinese, and she says the most difficult English word for her is "twelfth".
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curious, can she adequately differentiate her pronunciations of
pull pool poll and poe?
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don't know what that O looking thing is, but if he thought it was a smudge, he most likely thought it was an O too. which makes 4 vowels in a row?
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doesn't look like a d to me, because d's have that bit on the bottom and are very right heavy.
all that garbage is nearly centered on top of the circle, and it doesn't have that bit popping out of the bottom right.
i usually use a smaller font size
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It is certainly potential carbon neutral and could if used with carbon capture actual be carbon negative.
When combined with off-shore wind farm, using the off peak energy production this technology was some great potential that could even get the sceptics motivated by their addiction to gas guzzling on side.
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Wait, you can't use it to extract "Fuel" and then pump it back into the ground where the oil used to be?
Why stop there? Use it to make dinosaurs.
This is what I look forward most in hydrogen econ (Score:5, Interesting)
Get a farm, a solar array, some underground tanks, and you have unlimited fuel for your car and can heat your home in the winter for free. Gas stations will be something any Joe can make himself by installing a pump in his own personal system. The creation of the hydrogen gas is done on site with electricity and water.
That said, it will be a little while before we can all embrace it because economy of scale need to hit things like pressurized tanks and such. I'm interested in hearing about these other gases being made through solar energy though. I've heard other gases being used at powerplants and such, but I forget which ones.
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Re:This is what I look forward most in hydrogen ec (Score:5, Informative)
The hydrogen economy is, and always has been, a stupid idea. The cycle throws away two thirds of the energy for no good reason. And the fuel to store is detonation prone (not just deflagration), very low density, metal-embrittling, ignites with trivially weak static sparks (which common household devices are not rated to prevent), destroys ozone when it leaks, leaks trivially easily, and has a bunch of other nasty properties like pooling under overhangs, entering pipes from the outside, flowing to their destination, and then pooling there. People should read NASA's guidelines for safe handling of hydrogen - it includes things like for any building that handles more than a dozen or so kilograms at a time, the roof should be designed to be blown off in an explosion, among other gems. But all that pales in comparison to the main issue: the hydrogen cycle is just way, way inefficient.
Just stick with electricity. It's what you start with, it's what you want to end with... it's stupid to convert forms. (Okay, technically, storing in a battery is conversion to chemical energy, but it's extremely efficient in doing so - at least with modern forms like li-ion).
And no, hydrogen fuel cells are NOT "cheaper than batteries", they're absurdly expensive systems (and with, I should add, shorter lifespans than batteries to boot). A FCV with the performance of Honda Civic will run you several hundred thousand USD. And one should note that they still have to have a battery pack (hybrid-sized) to average out the demand fluctuations. And yes, batteries are coming down significantly in price (way more than fuel cells), and are predicted to drop even faster in the coming years due to developments like the gigafactory coming online.
Re:This is what I look forward most in hydrogen ec (Score:5, Interesting)
I think most sane electrolysis projects target methane as the ultimate product because it can be injected into the natural gas distribution network and is much easier to handle than bulk hydrogen.
Just stick with electricity. It's what you start with, it's what you want to end with... it's stupid to convert forms. (Okay, technically, storing in a battery is conversion to chemical energy, but it's extremely efficient in doing so - at least with modern forms like li-ion).
The thing is, if you're using solar and have no grid use for the generated power at the time of generation, does it really matter how efficient your conversion is? You're using energy that would otherwise go unused. It's free input energy and the output (if you target methane) is a form of storable and transportable energy for which we already have a storage and transportation infrastructure.
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The thing is, if you're using solar and have no grid use for the generated power at the time of generation, does it really matter how efficient your conversion is?
What matters is overall systemic cost. You should not install massive overcapacity of solar. It would be tremendously expensive, then you'd have to pay even more for inefficient recovery of some of the overcapacity. If we want to make real progress offsetting CO2, we can't waste our money like that.
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What matters is overall systemic cost. You should not install massive overcapacity of solar. It would be tremendously expensive, then you'd have to pay even more for inefficient recovery of some of the overcapacity. If we want to make real progress offsetting CO2, we can't waste our money like that.
Actually, you would want significant overcapacity of solar. First, if you're talking about a nationwide system, it evens out the loss of generation in areas that are occluded by things like storms. Second, you can use the excess generation to store energy for overnight usage. Third, is allows for portions of generation capacity to be taken offline for maintenance without reducing capacity below a level where you would need to burn fuels to make up the loss of generation capacity. Fourth, overcapacity would
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You also must consider replacement. If you install 15 times overcapacity of solar, and you replace the entire thing every 30 years, you'll remain under heavy financial burden. That does not even consider the great oversimplification some have in the
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I didn't say that you would want to go broke installing massive solar capacity. I said you would want significant overcapacity. I also didn't say that solar was the only option. In fact, I agree that the best energy source is a mix of sources tailored to usage patterns. I am also definitely one of the people that thinks nuclear is a valid power source.
15 times overcapacity is ludicrous. Not that I'm an expert, but you would want probably not more than 2-3X necessary capacity as an upper limit, and probably
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>Short peaks of overproduction for solar plants tend to run to several hours, which would be fine for a synfuel plant as described in the original article.>
No, solar overproduction may last 5 or 6 hours in the summer, but it drops to one or two in the winter, and practically none on cloudy days. Fuel process plants take time to heat up just to start processing, which can be on the order of hours depending of facility size, unless you have even more capacity to do rapid heatup. Startup cycle increases means efficiency reduction. You really want to run fuel production as close to 24/7 as you can or you are increasing cost significantly.
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No, solar overproduction may last 5 or 6 hours in the summer, but it drops to one or two in the winter, and practically none on cloudy days. Fuel process plants take time to heat up just to start processing, which can be on the order of hours depending of facility size, unless you have even more capacity to do rapid heatup. Startup cycle increases means efficiency reduction. You really want to run fuel production as close to 24/7 as you can or you are increasing cost significantly.
From the original article:
An industry that produces a synthetic liquid fuel can preferentially use a peak energy. I think we need to explore this idea more. For example, imagine collecting piles of recycled aluminum at a plant that uses great amounts of electricity to melt it down and turn it into ingots for industrial use. The entire plant could be designed to operate on demand and only now and then, when there happens to be piles of extra electricity in a clean-energy rich energy ecosystem, perhaps beca
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You clearly know almost nothing about the approaches and are just here to push a luddite political line - as shown from the previous discussion where you ran out the clock and claimed "victory" in some stupid argument game since there was no longer an opportunity to reply. For example:
Which of course is one of the many downsides of load following, especially with nuclear where the fuel is running out of life whether you run at f
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Here's what I don't understand -- what is "massive overcapacity" in renewables? Due to the variable generation they seem to trend towards a built-in overcapacity if there's any sane planning for average output.
Further, who or what is doing the overall systemic capacity planning for the entire grid? Nobody, really. Power utilities can capacity plan for their customer base and infrastructure, but they have no control over third party installations (at least for direct consumption).
Nobody but academic model
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If Grid MWH/day = X, you need enough overcapacity so that on cloudy days in winter, you still get enough energy from the panels or windmills to meet supply. That could mean as much as 15X depending on how you do the math and how much infrastructure you really have. For wind you might get down in the
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And you overcapacity is only available for short periods of time, you can ramp up a fuel production facility for just a few hours a day, not operate it on cloudy days, etc. Its just going to sit there unused over 80% of the time.
Yeah, but when you take into account the amount of solar available that remaining 20% becomes useful. The US produced 8.3 billion kwh of solar power in 2013. Using wikipedia worst-case efficiencies for electricity to methane says that's an annual production of nearly 29 million therms of gas.
And it doesn't necessarily have to be gas you use spare capacity for. What about making potable water from seawater or some other source?
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Forgetting the 'total grid overcapacity' scenario and coming back to where we are today, if a solar panel is in excess of 'grid capacity', society has the choice of using it to offset coal or gas generation, or to apply it in some other means as you suggest. The cost/benefit of choosing to offset coal even if you pay the fixed costs of the coal plant sitting unused is much better than any of the other scenarios if the
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I read this and I think "broken window fallacy" - because you need to build and maintain what will almost certainly b
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The hydrogen economy is, and always has been, a stupid idea. The cycle throws away two thirds of the energy for no good reason
You could have stopped there. This is just another energy storage approach, not an energy source.
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No, really. Doing some simple electrolysis and then converting the hydrogen for actual storage (chemically or liquefying) have a hideous energy cost.
Though I'm interested in what you'd get with a breakthrough in electrolysis, combined with use of a "reverse fuel cell" to make ammonia, if not some form of methane or syngas.
Other would be very small scale and short term hydrogen : to power a flame under a frying pan or wok etc. Cooking can be electric or from other heat sources otherwise but for some of the t
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The ideal fuel wouldn't be hydrogen, but something like propane that is relatively easy to store, is not a greenhouse gas if it leaks, and takes a proper oxygen/fuel ratio to ignite as opposed to being set off by virtually anything.
The ideal would be ethanol. It isn't toxic like methanol, has a decent energy per unit volume (not as good as gasoline or diesel, but not horri-bad.) Alcohol is somewhat corrosive, but nothing that can't be engineered around, and in Brazil, this is quite a solved problem.
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I agree, hydrogen alone is very difficult to deal with. It is much better to use the hydrogen as a feedstock to synthesize other fuels, fuels that have an existing infrastructure for storage and transport.
Propane is good but I'd believe that methane is better. Methane can be put into the national distribution lines that carry natural gas. The processes used to create propane and methane are identical to that for other, heavier, hydrocarbons like hexane, cetane, and everything in between. Those heavy hyd
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Again, don't care. Sunlight is essentially infinite for my purposes.
It's infinite because why, you have a robot slave army that will build by the thousand square kilometers in deserts? And what will you power the robots with?
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Fuel cells are the only way to get thermodynamic efficiency that is remotely competitive with battery electric vehicles. At the moment, fuel cells still have high initial cost, and short service life, relative to the batteries in battery electric vehicles. Sure, they'll ride down the price curve and up the performance curve as the technology matures. But then you get to the hydrogen. All sustainable, carbon-neutral methods of generating hydrogen involve using an energy source for electrolysis of water. Whic
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And "fuel cells" of the racing variety (i.e., another name for "plain old gas tanks" blow both those things out of the water in terms of overall utility. There is no point at all bothering with hydrogen fuel cells or batteries when we can just add carbon to our hydrogen and store it the same way as we've been storing petroleum for the last hundred years.
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It is a cool dream, but handling liquid hydrocarbons is a lot easier. If you have a good way to produce lots of hydrogen, you can 1) use it to synthesize hydrocarbons, which our existing infrastructure can handle, or 2) compress it to technologically challenging pressures or cryogenic temperatures, and still have low
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With the 1), where do you get the carbon from? :)
Getting CO2 from the air is a challenge. The meaningful proposals use industrial waste CO2 such as in a cement factory. We should probably tap these "resources" and make carbon fuel with them but once done I don't see how the tech can be further scaled up.
The "hydrogen economy" is a stupid idea (Score:2)
The fact that you think the technology in this article would bring about the hydrogen economy shows you misunderstood it completely.
This article is actually about solving the problem of the hydrogen economy (namely, that storing H2 by itself is needlessly difficult, dangerous and expensive) by attaching carbon to that hydrogen so that we can store it as easily as we store petroleum fuels today.
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Really? Hey I came up with a really good way to store hydrogen.
Attach the hydrogen atoms to a ring of carbon. Much more efficient than these ideas..
Other than the "liquid fuels" part... (Score:3, Insightful)
Re:Other than the "liquid fuels" part... (Score:4, Informative)
...you know what I could swear this technology sounds like? A motherfucking TREE.
A tree is less than 1% efficient. A solar panel is about 20% efficient. Trees need a lot of water, solar panels do not. Solar panels can put placed in a desert, on roof tops, or over parking lots. Growing trees for fuel displaces agriculture or wilderness.
Re:Other than the "liquid fuels" part... (Score:4, Informative)
1% Efficient at what? Converting sunlight to electricity? Please explain what you mean.
Trees are part of the wilderness - they don't 'displace' it.
Deserts are pretty much harsh environments because they are lacking trees.
Trees need a lot of water? Its stops if from running off, keeping the eco-system moist around them. They regulate moisture so that if rain is not falling, everything else around them doesn't die (including other smaller plants which also absorb C02).
Ever seen what happens to a river when you cut the trees around it? It shrinks. How would that happen if the trees were 'stealing' the water away from the river?
If there was salmon, it dies because of the rise in water temperature. What do you think the 'efficiency' of solar panels for that?
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There are only a few crops that can reach that kind (6%) of efficiency. 1% is a fairly typical number...
The 1% is for conversion of sunlight to cellulose. Then you need to burn that cellulose, to produce steam, and run it through a generator. That process is typically about 30-40% efficient. So sunlight-to-electricity is going to be less than 0.4%. A PV solar panel can do more than 50 times that.
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A tree is less than 1% efficient. A solar panel is about 20% efficient.
How is it "only" 1% efficient? I can't find the exact reference at the moment but I think I heard that photosynthesis is ~99% efficient (Take that with a grain of salt since that is relying on my memory).
Apparently it appears some complicated quantum effects take place in the photosynthesis process. Some info is presented on (possible) quantum behaviour in biology by Prof Jim Al-Khalili in in this Royal Institution Lecture [youtube.com]
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See https://en.wikipedia.org/wiki/Photosynthetic_efficiency [wikipedia.org] (and its references).
According to that, plants are typically 0.1%-2% in sunlight-to-biomass efficiency, with sugar cane reaching at most 8%.
Simply the "47% lost due to photons outside the 400–700 nm active range" makes it not 99% efficient.
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Years ago (back in the 70s) I recall a study about harvesting energy from sunlight which compared PV cells, heating water passing down black pipes, reflecting sunlight to a focus point to heat water.... and the most efficient (though probably not scalable easily) one tried was similar to this.
1) Put some plates of wet glass in the sun** and wait
2) Scrape off the algae that forms for free, put the glass plates back
3) Ferment the algae with some yeast to make (mostly) ethanol & water
4) Use sunlight to he
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Their solar panels weren't very good at the time and it does need a ton of handling compared to solar panels.
The only way I see algae harvesting being economic is with plastic "ponds" on the ocean, area is cheap, don't have to pump water (open systems like the one you describe need it) and don't have to worry about overheating (closed systems do this). Put the gasification+FT close by and recycle the ashes back into the ponds.
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Conversion efficiency is not the end-all of measurements. A tree grows for free. A solar panel costs money. So a tree is infinitely more efficient than solar panels in $ per Watt-hour. The only time conversion efficiency is relevant to solar is when you're space-constrained (or in the case of PV panels, constrained by construction costs per square meter of panels). A solar panel makes sense when you're limited to a small area, lik
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Humans do silly thing like monoculture "replanting" forests that don't do that well (source : I read some stuff about that happening in China). Anyway : trees for fuel can sustain a Roman Empire or modern "pre-industrial" type of civilization, barely.
So I wonder what would be the plan : wait 30 years for forests to grow, then divide the GDP by 50 and chop the trees slowly enough.
Re: Other than the "liquid fuels" part... (Score:2)
It Works. The only ? is (Score:2)
How efficient is it? We are a long way from knowing.
easier method of creation (Score:2)
There is an easier way to create the methanol in the article. Methanol can be easily and efficiently made from coal.
Two thoughts (Score:2)
How well do these systems work when their feedstock of CO2 is less than 0.5% pure (i.e. air)?
One of the niches they're looking to exploit is when renewable energy sources (primarily wind) are oversupplying so you can get your electricity very cheap or free (but only for a fraction of the time.) For this, they are going to be in competition with various industrial scale electricity storage technologies, which are not yet commercially viable in most situations, but are advancing and probably closer to viabili
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you're only out by a factor of 10. According to Bitesize, atmospheric CO2 runs about .04%. There's 24 times more argon in the atmosphere.
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You're right. I took 400ppm, turned it into 0.4 parts per thousand and then forgot the factor of ten for per-thousand to percent.
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A point to fancy, as long as we're talking about the atmosphere, is that it already contains fully-formed fuel, ready to use if you can extract it: 1.79 ppmv (volume concentration) of methane and 0.55 ppmv of hydrogen. Now, rare as those portions are, there is a hell of a lot of atmosphere; 5.15x10^18 kg. Methane and hydrogen are less dense than air, so the mass concentration works out to around 0.9 ppmm for methane and 0.04 ppmm for hydrogen, but still there are many billions of tons of them in the atmosp
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There are places where the concentration is much higher. For instance, the smokestacks utility-scale, fossil-fueled electrical generators. For instance, there are a variety of large coal plants out in the Arizona and New Mexico deserts, which also have abundant solar (PV and thermal) resources. It may seem a bit strange to co-locate a liquid fuels synthesis plant, hopefully run on variable renewable energy, ne
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I agree, you can't get the atmospheric CO2 easily.
That carbon is useless. On the other hand, you do have 80% N2 floating around, won't run out anytime soon.
so many things wrong with EV tech pushing (Score:2)
I'll start with a basic thought experiment in which I invite the reader to begin with some assumptions:
1. That conversion of energy from one type to another suffers a 50% loss in efficiency.
2. That charging an EV involves plugging in to the line supply.
That's those, now the numbers bit.
start with 100 units of energy contained in coal as your primary chemical potential.
Generate some electricity with it. OK, this is lots of burning and turbine spinning and stuff, but with the assumption you're left with 50 un
Re:so many things wrong with EV tech pushing (Score:4, Insightful)
Transmissions systems for electricity are way way more efficient than you suggest. In Great Britain transmission and distribution losses run at around 7%, and that is from the power station into the home/business. Expect these losses to fall as we move to HVDC transmission.
The next glaringly obvious mistake is that charging a battery is not 50% efficient either. It is typically around the 85% efficient mark. If you Goggle it you see a Tesla Model S turns 82% of the power at the wall into power in the battery.
With two such glaring mistakes I can only presume that your post is meant to spread deliberate misinformation.
Re:so many things wrong with EV tech pushing (Score:5, Informative)
* Power transmission is not anywhere near as inefficient as you suggest. The UK National Grid for instance suffers losses of only 7% power station to consumer.
* Electric motors are not anywhere near as inefficient as you suggest. A decent brushless motor will do better than 90%
* Batteries are not anywhere near as inefficient as you suggest. A good Li-Ion type battery has an efficiency of over 90%
So, a petrol engine is not demonstrably more efficient. Overall, electric vehicles significantly beat petrol (gasoline) engines for thermodynamic efficiency even including power generation losses (a large generator tends to be more thermodynamically efficient than millions of tiny ones). Then add to that an electric car can effectively be nuclear powered or wind powered or solar powered or combinations of those if they are the local generating plants.
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I will not argue that electric vehicles are more efficient than petrol powered vehicles. There are still several problems with electric vehicles that are far from trivial.
First problem that comes to mind is range. Even the best electric vehicles on the market today have a range that is half that of a common petrol vehicle. These petrol vehicles come in a variety of shapes and sizes from tiny little econo-boxes to luxury SUVs and tractor-trailers. A full recharge on these very expensive electric vehicles
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So you saying your have never even sat next to an electrical engineer on a bus one time.
Electrical generation is primarily steam, the waste product is primarily heat. Heat can be useful everything from desalinating water, splitting water for hydrogen, growing algae as feedstock for biodiesel, animal feed etc etc. You're correct a typical commercial steam turbine has a max theoretical efficiency of 60% or so according to Carnot's law and about 50% in the real world.
The grid 90+% efficient and getting bette
Worthless (Score:5, Informative)
Making fuels from sun and air sounds like a tree huggers dream but as long as we can find something cheaper it will be useless.
We've all heard the phrase that time equals money, and there is a lot of truth in that. Time is money, energy is money, a lot of things are money. To make fuel from "free" things like sun and air will take time, labor, energy, and other things that require money to buy. This is going to be very expensive.
What I see as more promising is some research done by the US Navy where they want to make jet fuel using sea water. The US Navy found that it is much easier to get CO2 from water than from the air, meaning it takes less time, energy, and therefore less money. As a byproduct of the CO2 extraction they get hydrogen gas, which is fortunate since with the CO2 and the hydrogen they have the raw materials needed to make jet fuel. The energy required would come from nuclear power, something that the US Navy is very good at managing.
I believe that if we are going to see a leap forward in energy technology that it won't come from the tree huggers. I believe it will come from military research.
Also, in the linked article (yes, I did read it) there was a comment about shutting down an aluminum plant when there was not enough energy, one does not shut down an aluminum plant on a whim. Once everything in a smelter gets hot it is so much easier and cheaper to keep it hot. If allowed to cool then it takes a lot of time and energy, which means money, to heat it back up again. There is also the issue of continued heating and cooling stressing the equipment, that means repairs and more money.
I've seen a lot of people that think we can shift the load to match the supply but that does not work well in a real world. We can shift some loads to off peak times but at some point we are simply going to have to build more supply so that people can do their work on schedule. If production shuts down for lack of sun then that means time lost, and money lost. Solar powered anything is going to have to be so ridiculously cheap or people will go elsewhere, and I've never seen cheap solar power.
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Actually this would work great with nuclear power and would end up being cheaper than using solar.
People have to understand that the idea of "you make it when you have sunlight" thing does not work. For the employees it is "sorry but you do not work today or get paid because it is raining" just does not work.
The big costs will be the plant and the people and to get your investment back you need to run the production all the time.
A processing plant you can only run 8 hours a day on average is going to cost 3
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He describes what he thinks could be an electricity to liquid process competitive with fossil fuels (he envisages to be used with nuclear power, but it's still an electricity to liquid process) and you use that as an argument for the impossibility of storing sunlight. That's a bit non sequitur.
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The linked article was written by a nitwit. Here's the actual text you want to read:
http://www.sciencemag.org/cont... [sciencemag.org]
Technical analysis (Score:3)
Have you ever looked at trend lines for PV electricity cost? If you want to build a nuke plant with private money they are downright scary and with HVDC distribution isn't much of an issue either. If the US navy manages to cheaply convert electricity to liquids that could be even better for solar than nuclear, if the trend lines hold. As a money man you should have some respect for technical analysis ;) It's mostly bullshit, but in the absence of known physical limits it's as good as any other guess on the
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Have you ever looked at trend lines for PV electricity cost?
I just did look and the gains PV has made in turning dollars to watts and joules and it is impressive. Even with these impressive gains solar PV is still somewhere between double and tenfold what energy from coal and nuclear cost, depending on location and who is doing the math.
While the costs for PV is lowering with time so is nuclear. Both must hit bottom at some point and I don't believe the trend lines will ever cross. I say this because of a very real problem with solar power, night. Nuclear power
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We already have a cheaper way to convert sunlight and air into fuel. We don't even have to manufacture them - they self-assemble themselves. They're called plants.
If the subsidies for biofuels weren't being diverted by the horribly inefficient corn lobby, we might actually be making some progress converting generic cellulose into alcohol fuels on an industrial scale. Once you
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We already have a cheaper way to convert sunlight and air into fuel. We don't even have to manufacture them - they self-assemble themselves. They're called plants.
You apparently have not read the article. This technology promises to turn sunlight into liquid fuels with an efficiency above 50%, nothing in known biology can get even close to that.
There are other advantages to this technology besides efficiency when compared to bio-fuels. This sun to fuel technology does not compete with food for resources like water and fertilizer. It might compete for land but presumably these sun to fuel factories can be placed on land not suitable for crops. I will also assume t
already a better way... (Score:2)
4 letters... L F T R
In fact, I watched an very interesting proposal by someone in the state legislature in one of the western states of the US that was trying to push a proposal to use a LFTR reactor to turn their coal (primary source of income for the state) into liquid fuel because the cost would be negligible with a super high heat thorium reactor. No need to make fancy next-gen generators.. they could exactly model the already proven design they had at Oak Ridge to provide the heat and hey presto! In
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Please, breeder reactors are severely overrated. They make stuff more complex and expensive - such as needing an extremely expensive processing plant on site, and there's no shortage of conventional nuclear "fuel".
Thus I would favor a very high temperature reactor that's a non-breeder and runs on uranium, though it has to get proven and to make a real difference you'd have to build 50 or 100 of ta given design, and quickly. For now I don't see how that will get done.
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It is a breeder, but from reading the page it breeds with slow neutrons. (as do even regular reactors, but less fissile fuel is created than consumed)
I did not know that.
Electric lawn tools (Score:2)
Every electric lawn care tool I have ever used has sucked. I mean really, really sucked hard! They just don't have the torque to get a job done well, they take forever to charge and you are lucky if you finish before the battery runs out. The only exception that I know of is chorded electric hedge trimmers. But.. it is so easy to accidentally cut the cord. I actually prefer plain shears!
I know some people do like electric lawn tools. I can't fathom it. I think maybe those are people who grew up with them
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Unfortunately, the set of cheapass crap lawn tools and electric lawn tools have a lot of overlap.
If anything, electric tools can have more torque, more cheaply, than a gas tool, but they're just made with as few corners as possible. Pretty tragic, if you ask me.
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What about mechanical lawn movers that you push, putting in motion blades that will cut the grass? Sounds fun.
The Science of how this works (Score:2)
Nothing new, 10+ year old R&D area (Score:2)
There has been dozens of "promissing" solutions to make liquid fuels from sunlight.
Dates back to G.W.Bush mandate.
Celulosic ethanol enables making ethanol from grass and wood. Let the plants do it.
Use genetic engineering to make diesel / jet fuel like compounds from bacteria / algae.
Much like revolutionary batteries, 90% of announce techs never leads to anything commercial.
Let's focus on real technology like solar PV / solar CSP / wind turbines / improving Li Ion economics / breeder nuclear reactors.
Yes, I
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With less people on the planet it would be an option, of course with enough people on the planet we run out of options real quick regardless.