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Making Liquid Fuels From Sun and Air
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.
Sure it's not carbon capture, but it is renewable.
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
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?
Did you know 80 to 90% of the moderators on slashdot wouldn't recognize a troll even if one dragged them under a bridge.
The hydrogen economy probably won't be on us for at least about 5 years if it paces itself at a break neck pace. The dream of having a farm with solar panels, converting water to hydrogen to store in tanks in the ground is a cool dream. You can then use that hydrogen to power your car or heat your home. The key is that the tanks haven't hit an economy of scale yet since the commercial hydrogen car just came out by Toyota this year. In the short run Hydrogen is expensive as all get out, but in the long run it can be cheaper than batteries. A battery array likely won't come down in price nearly as much as a pressurized tank will.
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.
God spoke to me
oh forgot to add a link. Check out r/htwo on reddit.
God spoke to me
...you know what I could swear this technology sounds like? A motherfucking TREE.
How efficient is it? We are a long way from knowing.
If you use trees/plants as a carbon capturing device for say 5-10 years, then you just put them in a gasifier and get basically natural gas to run an engine/generator. Been done since WWII.
http://www.sciencemag.org/content/349/6253/1158.full
This is Iron-Mans boot jet. Works very similar to this. http://www.eliotrbrown.com/art...
Mission critical backup generators that you hardly ever need but are life or death are probably best run on liquid fuels stored long term, like at the South Pole research station or in any hospital.
Um, no. Refined fuels are enormously hydroscopic and have a limited life span. You don't store them long term.
http://www.sciencedirect.com/s...
They can make formic acid much more efficiently than methanol, and it is actually a better option for fuel cells since it does not cross the polymer membrane.
There is an easier way to create the methanol in the article. Methanol can be easily and efficiently made from coal.
Why on earth would any hospital pay $10/gallon when they can pay $4/gallon?
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 viability than these technologies.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
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.
Sun evaporates water
air gets moist
clouds form
sun warms air
wind moves clouds somewhere else
rain forms
rain fills reservoirs
water turns hydroelectric turbines
water returns to catchment
repeat
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.
"This administration is so incompetent that they cover their tracks with bigger tracks." - Seth Meyers
There is no such thing as 'catastrophic man-made global warming', hence they renamed it 'climate change', which is a meaningless term, because the climate is ALWAYS changing. But 'climate change' is ALWAYS meant to be taken to mean "catastrophic man-made global warming'. How dishonest.
www.climatedepot.com
www.wattsupwiththat.com
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 units of electricity.
Send that out over the transmission lines, step it down in the local substation to domestic voltage, you're down to 25 units (substations generate a LOT of heat and quite a few of them buzz).
Now you're at the power socket, send those 25 units into the vehicles battery. You're down to 12.5 units of chemical potential stored in the battery.
And not the final step, turning that chemical potential into DC for the motor: you're down to 6.25 units.
And the motor driving the wheels that meet the road, you're getting use out of 3.125 units (losses due to friction, &c.). 96.875% of the energy stored in that coal at the power plant is WASTED.
Sure, EV motors might be 50% efficient but only if you IGNORE what happens between mining the coal and storing chemical potential in the batteries.
Battery powered vehicles are a tertiary method. A 25% efficient petrol engine (a primary traction engine) is demonstrably more efficient than an EV. I just did that.
Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
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.
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.
I am armed because I am free. I am free because I am armed.
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. Which takes as much energy as the hydrogen itself will release when it is "combusted" with atmospheric oxygen back into water. Adding insult to injury, hydrogen is a gas at standard temperature and pressure. In order to carry a quantity sufficient to provide useful driving range, more energy must be expended to pressurize the hydrogen to thousand's of PSI for storage on-board the vehicle.
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! Instant liquid fuel that is 100% compatible with our current liquid fuel infrastructure. While not ideal this does open the door to better applications.. like harvesting the C02 needed for the reaction from the air, thereby making the reaction sustainable and essentially carbon neutral. All you need is lots of power to make it happen, specifically lots of power in the form of heat. Stop playing with fresnel lenses and start building LFTR's damn it!
If I sound stupid, it's not me talking....
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 lower energy density. You don't need pure hydrogen to run a fuel cell - a variety of fuel cells you can buy today for powering a home or datacenter run on natural gas.
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.
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.
add to that the need to transport hydrogen to vs electrical distribution via the grid. We have infrastructure already for the latter.
....you know what I could swear my car sounds like? A motherfucking PLANE.
Audi has built an industrial scale plant that converts renewable gas to chemical energy ( although not liquid) see http://www.audi.com/content/com/brand/en/vorsprung_durch_technik/content/2013/10/energy-turnaround-in-the-tank.html. Actually, if commercially viable, converting electricity back to nautral gas as this plant does is a very bright idea. In Europe we already have infrastructure to transport gas so this seems a good way for storing excess energy.
Solar is free energy, except for the politicians that think they get to charge you for it.
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 allow you to pull CO2 out of the atmosphere for no other purpose than to remove it from the atmosphere.
Yes, it would be expensive. But, it would be expensive in a "it costs a lot right now, but is almost free (and may be revenue positive) later" kind of way.
No, you don't want to go broke installing massive solar capacity. It will take so long and so much money we'll never achieve CO2 reduction goals. Wind is a much better option. The best is a mix of wind, solar, nuclear, varying depending on country, and locale.
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 their minds about what it would take to modify the grid to accommodate such a scheme. Costs of adding transmission lines alone would be brutal (not just material cost, but land acquisition, enviro studies, NIMBY and envrio lawsuits and associated delays, etc).
And will all that, you can't just ramp up a 'synfuel' plant for the short peaks of overproduction. You must plan that into your total capacity and multiply it for overcapacity, otherwise you'll have mounting fixed costs on the fuel production equipment even further raising the cost of the produced fuel.
Those are just a few of the cost issues at hand. The world does not have unlimited funding. I think some folks prefer the dream of "all solar/all wind" over actual CO2 reduction progress.
It also will lead to a few companies and a few top exec's and their families becoming the most powerful and wealthy people on the planet because people are addicted to fossil fuels. Even though this might be better, just like the Navy's sea water to fuel tech, it will create an unlimited, guaranteed income for the people who control it. They will be able to buy people and elections, along with spreading mis-information about any competing product.
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.
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
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.
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
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 and never experienced anything better. Or.. maybe people who are to weak or arthretic to pull start an engine.
So.. that's my continued use for liquid fuels after we all switch to electric cars... cutting the lawn. Unless.. OMG! Do elecric cars suck as bad as electric lawn tools?!? I've never used one. Does anyone care to comment? (electric law tool lovers need not bother) Is that the future we are moving towards? Maybe I'd prefer to just melt the glaciers. I don't live by the ocean anyway.
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 modelers and maybe utilities are looking solar buildout capacities from a CO2 offset perspective, and with utilities the math is even more complex because they have to look at baseload and peak load, too, for which CO2 offset number may make more sense with natural gas over coal.
If I put 15kw of solar on my property to offset my 15kw use, it's technically overcapacity from day 1 from an overall grid capacity because the grid already had capacity to meet my consumption. It's not overcapacity for me because only at magic moments is it actually outputting 15kw and even then I'm at net zero or optimal capacity.
Power companies are already fighting back against large "solar gardens" here in Minnesota. Pick your explanation, but they more or less all boil down to "systemic cost" -- the cost to maintain fixed generation facilities, adapt the grid to new multi megawatt power sources, etc.
If you have a farm, you can grow all of your own food, reducing the need for an external job and the car ride to job. You don't need any special tanks to run the occasional farm implement of destruction device.
You can buy solar panels at $0.29/wp right now at retail. That's $0.03 more expensive than hydroelectric (all things considered) and the price is still coming down.
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 less. That allows for variations in generation without excessive overcapacity.
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. If generation drops off, electricity can be purchased from other sources in order to run the plant until generation comes back up, or until the plant can be shut down. Also, WRT to solar, as generation falls in one area it tends to rise in other areas. That offsets the loss, which keeps generation levels near a given level.
Those are just a few of the cost issues at hand. The world does not have unlimited funding. I think some folks prefer the dream of "all solar/all wind" over actual CO2 reduction progress.
I never meant to imply that there is unlimited funding, nor that wind/solar is the one and only answer. They are simply parts of an issue that is far too complex to have only one valid answer.
Old science.
It's called photosynthesis.
Overcapacity is the installation of enough solar (or wind) to carry the entire grid demand. This assumes storage capability for solar at least. For wind, it is the 'wind is always blowing somewhere' scenario.
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 5 to 10X range.
If you assume a mix with something like nuclear and gas, it gets much easier, much less expensive. That is not the scenario hinted at the post I was responding to. Your individual scenario is a different point altogether, as you are looking at our scenario, not the whole world scenario. Your overcapacity right now is purely incentive driven. 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.
And yes, power companies are fighting back due to systemic cost concerns. But mostly to at least recover fixed costs and get the proper value of the backup generation and grid they are supplying to residential solar users. We all pay one way or another, the power companies are just a piece of it. Right now, the market has been skewed by incentives and that includes a tremendous undervaluation of reliable reserve, which has a much higher value in this whole process than many seem to think or at least want to pay for (IMHO). That is a different topic that what I was addressing though.
That is not a comparable cost unit. Try MWHrs/Year.
I read this and I think "broken window fallacy" - because you need to build and maintain what will almost certainly be some complicated and finicky machinery just in case you're generating power and don't happen to need it at that moment. Just because the energy is 'free' (it actually isn't) doesn't mean it makes sense to go to elaborate lengths to not 'waste' any.
>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.
And I care why? That energy came from the sun and was going to be left unused anyway.
Buried tanks make this a non-issue. It's not near any source of ignition, and if it detonates, it just blows up its own tank and some dirt.
Again, don't care. Sunlight is essentially infinite for my purposes.
Glass-lined tanks are a thing, you know. Hell, a thermos is a hand-held glass-lined tank.
Probably not within a buried (read: electrically grounded), glass-lined tank.
Ozone is toxic and is considered a nuisance at ground level. In the upper atmosphere, where ozone is helpful, hydrogen is already plentiful and is not hampering the ozone layer in any way shape or form. Fluorine is a much greater threat to the ozone layer.
See the parts above about infinite input energy from the sun and not giving a shit about ground-level ozone destruction. Also, glass-lined tanks leak far less because of the properties of glass.
Not a major issue if there are no significant overhangs near the tank. If you bury the tanks in a safe manner (that is, away from other structures), that should be exactly the case.
The equivalent for a buried tank in an open area away from other structures is a pipe stack with a blow-down valve. Incidentally, this is a standard recommendation for any buried tank.
Which doesn't matter, because it's simply a method of capturing "scrap" energy from the sun. That energy was going to waste anyway. There's no loss possible in this equation, because even the tiniest amount of captured energy is a net gain. Period.
A set of hydrogen/oxygen tanks is also just a massive chemical battery. The difference is that you're not using electrical charge to force electrons to jump into an overcharged plate, but you're instead separating a chemical compound into its elements for recombination later. That recombination will extract a small portion of the energy put into the breaking-apart of those elements. But the energy going into that process was free anyway, so you are actually getting something for free. This is the fabled free lunch. It's just not a very large lunch.
http://www.sciencemag.org/cont...
Not the gibberish version the editor chose to link.
Isn't it called photosynthesis?
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?
There is no 'remaining 20%", it is being used by the hypothetical fuel production plant.
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 goal is to offset/reduce carbon emissions. It is not even close.
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 bounds of solar electricity cost.
Area is not a problem for the US either, it has plenty of deserts with good sunshine (it is obviously a problem for the EU).
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?
It absolutely matters. You fill up your energy storage off-peak when prices are low, then convert back to electricity to sell to the grid on-peak when prices are high. If your energy storage mechanism is less efficient in converting back and forth, you get less MWhs to sell back into the market. Of course you also have to factor in cost of the storage and calculate the payback periods of the various options to determine which is the best option.
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.
With a bunch of LFTRs (Liquid Fluoride Thorium Reactors a type of Molten salt reactor) you could produce all kinds of liquid fuel from the electricity generated by the reactor, plus you could create tons of fresh water. All with hardly any nuclear waste at all, or any fear of nuclear melt down.
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 because it is sunny and windy and other demands happen to be low. The employment structure of the plant would also be designed to do this, drawing on-call workers off of other activities to run the plant. This would essentially amount to carrying out a high energy demand industrial task with free energy.
It's not the most efficient thing, nor is it an all the time thing. It's not meant to be. It's just something to do with excess energy when you have too much of it. If you don't have the excess energy, then it doesn't get done. So maybe you only make liquid fuels using excess energy in whatever hemisphere summer happens to be in at the moment. Also, the closer to the equator, the less that daylight variability thing is an issue.
I believe that you and I are close to agreement on what can be done. Where we seem to differ is what should be done. You seem to desire an optimally energy and cost efficient system. On the other hand, I believe that a less efficient system with the possibility/probability of excess generation is perfectly adequate, as it provides for a greater flexibility. I don't condone waste, but I am willing to accept 'good enough' as just that, even if there is something potentially better.
Well, I don't agree with the suppositions of the article. And yes you seem reasonably aware that the holy grail of all wind and/or solar just is not feasible. But I'll clarify my position, I am not for the most energy efficient and not necessarily the most cost efficient. I am for the approach that I think gives us the best chance of succeeding in significantly reducing carbon emissions. To give us the best chance, cost factors, social factors, and other challenges must be accounted for all the while not depending on hope for the big breakthrough instead of taking action where more certainly exists.
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 tasks the good old gas flame is very nice. Making a flame on site from water and electricity would be nice.
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?
I know that panels are cheap, but there are five parts to a solar charging system if off-grid, four if on grid:
1: The panels themselves.
2: The wiring.
3: The inverter (if on grid), or the charge controller
4: The battery bank.
5: The inverter if off grid.
Panels are coming down in price to a point where solar is a "why not" thing, as opposed to "why", especially with RV-ing. However, wiring is expensive, proper attachment of terminals is quite costly [1], and quite overlooked, causing people to wonder why the solar charger never tops off their batteries, but due to the voltage drop, it can't achieve the voltages required for 100% SoC.
Then there are charge controllers. You are not getting a MPPT charge controller for less than a "C" note, and an $8 eBay PWM controller isn't going to jack with 12 volt panels, and with 24 volt, it will "lop off" about half the incoming wattage in order to provide the proper voltage to the batteries. If the CC doesn't have an inductor, it isn't MPPT, no matter how much the eBay seller promises the "Sony guts" are there.
Batteries are important as well. Every other facet of solar is moving along, but batteries. We are still stuck with the same flooded lead/acid stuff that we were using 50 years ago. Lithium-ion? Overcharge or overheat those, and one will get familar with the term, "runaway thermal expansion".
Finally for an off-grid system, there are inverters. Again, you can get a cheapie MSW, or pay more for a pure sine wave output.
Last of all, don't forget that it takes more energy (coal, oil) to make a solar panel (frame, silicon, wires) than the panel will ever recoup in its operational life.
[1]: Take 0 gauge cable for instance. For a proper crimp for marine/automotive/RV work, it requires a hydraulic tool that can put pressure on six sides at once for an airtight hexagonal job, and do this twice on the connector. Trying just to squeeze the connector with a set of pliers will just mean a flaky, corroded connection in a few years, especially if outdoors. Solder and shrink wrap insulation do help, but the main thing is having a proper crimp in the first place.
Fair enough. I think the original article has a fair bit of pie-in-the-sky optimism myself. I can't disagree with the one point that liquid energy storage will be with us for a while though. If we can shift that to a source that is more carbon-neutral without excessive cost, I'm all for it.
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.
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..
So other than the fact that your car flies through the air, a plane would almost do the same job except a lot more efficiently and for free?
Last of all, don't forget that it takes more energy (coal, oil) to make a solar panel (frame, silicon, wires) than the panel will ever recoup in its operational life.
The existence of residential and utility scale PV installations, in combination with basic economics, suggests that your statement is false. Unsurprisingly, actual studies prove that is false: Pants on fire!
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 hydrocarbons are liquid at atmospheric pressure, and are the primary components of gasoline, kerosene, jet fuel, diesel fuel, and fuel oils. There is definitely a market for these fuels and an infrastructure to transport, store, and consume them.
I also believe that if we see a hydrogen economy that it will come in the form of hydrocarbons but also as ammonia. Ammonia is used as a fertilizer, industrial feedstock, and as a fuel. Ammonia is even better on the environment than propane and other hydrocarbons in the case of leaks and spills. Plants and animals can process them naturally and is not carcinogenic like hydrocarbons. Ammonia can be mixed in with other gasses to produce an analog to natural gas. The nitrogen needed as feedstock for ammonia production can be drawn from the air, which is a trivial process.
Ethanol, like ammonia, is relatively safe to plant and animal life which does make it a very practical fuel. It does have the tendency to damage seals and lubricants that are common for fossil fuels so it cannot fit as seamlessly like synthetic hydrocarbons into existing infrastructure. There are also legal obstacles for its use. I've spoken with people that make and use ethanol for various things (fuels, industrial solvents, disinfectants, and adult beverages) and the US ATF keeps a close watch on anyone that creates or consumes even relatively small quantities. If we are going to see large scale use of ethanol as a fuel, not just a fuel additive as it is now, then we need to see some big changes in the US tax codes first.
I am armed because I am free. I am free because I am armed.
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 full power or not, or coal where reduced capacity requires not a lot less fuel than running at full capacity - but the main thing is a dramatic amount of life reduction of the equipment from variable loads producing variable stresses.
I also think you should apologise for your blatant lie about your background. Back in the day my first year students knew far more about these topics than you so your pretending to be a professional engineer is a disgusting kick to the face.
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 consider nuclear fusion another type of "promissing" technology that never gets anywhere.
However I'm always hopeful.
Is your new brain on backorder or something?