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Isn't that fraction of a CC just a byproduct of the photoreforming of cellulose in the grass to glucose? A good way to convert cellulose to glucose would be a big deal. I may be missing something, however, because the mention of subsequently converting the glucose to hydrogen and CO2 doesn't fit. Normally glucose is fermented into CO2 and ethanol. I don't know, offhand, of any easy process to go from glucose to CO2 and hydrogen, even though it's theoretically possible.
I don't think we have sufficient battery production capacity as yet or battery charging capacity to electrify heavy trucking. When you have a limited production capacity that you want to ramp up, it makes sense to target the market segment where your product will have the highest specific value -- i.e., where it will fetch the highest prices. That would be cars and scooters, not trucks. The cost of batteries isn't as big a hurdle in that market as it would be for trucking.
These lightweight materials can withstand a load of at least 160,000 times their own weight. Statements like that in popular articles really bug me! Totally meaningless. It would have been more honest for the reporter to have written "it's really really strong, dude". As it is, it's made to seem like a technical statement, conveying quantitative information. But it's not. It's gibberish, like talking about how many acres there are to a mile. It's in a quote attributed to one of the researchers, who presumably knew better. My guess is that he was speaking in the context of a specific size block, perhaps a 1 cm test cube. Then the statement would be meaningful. It would mean that a one cm cube of the material could support 160,000 copies of itself stacked atop it -- a column height of 1.6 km. That's not bad, but hardly spectacular. Modern steel is better. OTOH, had he been talking about a one meter cube, then the self-supporting column height would be 160 km. That would be impressive. But we don't know, because the reporter didn't realize that the block dimensions would be relevant, and didn't mention it. "160,000 times its own weight" sounds so impressive. Never mind that even a weak material, like chalk, can easily support 160,000 times its own weight, as long as you're talking about a small enough piece. Square-cube law, dude!
Hydrogen for refining of heavy crude is already supplied, in nearly all cases, by steam reforming of methane -- the SMR reaction. This "invention" appears to be saying that, hey, we can use methane from biogas instead of, or to supplement, methane from natural gas. Well, duh!
I'm surprised that they're suggesting methane as the "gas" part of the proposed "VGV". If one is going for efficiency, it's best to stop at hydrogen, rather than going on to make methane from hydrogen and CO2. Only 50% round trip, but that's a lot better than the ~25% you're looking at with methane. OTOH, if one doesn't care about efficiency, then there's no reason to limit the synthesis to methane. You have to start with H2 + CO2 -> syngas in any case, and from syngas you can make most any hydrocarbon you want. Methane may be the easiest and most energy efficient, but methanol, ethanol, DME, and Fischer-Tropsch liquids aren't that far behind. What they should be proposing is establishment a broad synthetic hydrocarbons industry based on hydrogen from surplus electricity of any sort -- excess nuclear or intermittent renewables. It's not really hard to buffer enough hydrogen to absorb even seasonal imbalances between supply and other demand.
I'm having a little trouble understanding the chemistry here. I don't see how it's possible to produce hydrogen gas from seawater without producing a corresponding volume of either oxygen and / or chlorine. The article is behind a pay wall, so I can't check it. Did the summary simply fail to mention the oxygen or chlorine? There's a very efficient way to do most of what they're talking about: electrodialysis splits a volume of seawater into an acid portion and a base portion. The acid portion is then neutralized by dissolution of silicate minerals; the base portion is diluted and released into the ocean to counter acidification and pull CO2 from the atmosphere. Very energy efficient, in part precisely because it doesn't produce hydrogen gas.
What they're doing is steam reforming of methane, using solar heat to supply the reaction enthalpy for the endothermic reforming reaction. Makes sense. In conventional steam reforming, the enthalpy is supplied by partial combustion, which reduces the yield of synthesis gas. If they can manage the SMR reaction in a small reactor at the focus of a solar dish, they should also be able to take it to the next level. By capturing some of the CO2 from the turbine exhaust and feeding it back to the the input stream, it's possible to further enhance the yield of synthesis gas. Some of the hydrogen produced by the SMR reaction combines with CO2 in the reverse water gas shift reaction, giving CO and water vapor. With the combined SMR and RWGSR, could be boosted by 50%, rather than 20%. By storing some of the synthesis gas produced during the day for burning at night, what you've achieved is the holy grail of renewable energy: economical stored solar energy.
@ Jus7tme You're overlooking one big factor with e-gas: Germany, especially, has a big problem with surplus wind energy during periods of low demand. The power that will be used to make e-gas is essentially free; it would otherwise be wasted. Other things being equal, it would admittedly be more efficient to use the power to charge EV batteries. But EV batteries are still very expensive for the energy they store. E-gas taps into an existing gas infrastructure and delivers far better driving range.
Color me skeptical. Inductive charging while a bus is stopped at an appropriate station can certainly be made to work. However I see no significant advantages -- and several significant disadvantages -- over the alternative of direct charging from overhead power rails. The fraction of time that the bus spends stopped at a station is small. That means that operation of the charger is in short bursts, with very low overall duty cycle. That taxes the power delivery lines to the charger and requires both the stationary charger and the mobile receiver to be heavy duty and expensive. With overhead power rails, the bus can draw power over 90% of its route distance. The power lines need not be continuous. That avoids the complications of dealing with route crossings and splits, at the cost of requiring robotic contactors that home in on the rails in sections where they are present. That's no problem, however.
One thing that would help would be for someone to get on the stick and develop range extender trailers on the model of the prototype that AC Propulsion built for its T0 electric. Bumper-hugging, self-steering for easy back-up, streamlined, low aerodynamic and rolling resistance, carrying a super-efficient constant-power generator that can recharge the vehicle's batteries on-the-go. Rent one for long road trips, or when extended operation away from charging stations is needed. There could be different models available for different amounts of luggage space, and perhaps for different fuel types. A model running on compressed or liquefied natural gas could connected to a domestic gas line as an alternative to heavy duty electrical service to the home for fast charging. In tandem with the vehicle's batteries, it would make for a great back-up power system for the home, or for vehicle-to-grid ancillary services.
Torrefaction + grinding gives a sort of sawdust that's similar in density to chipped branches, but super dry and higher in energy density. It's also denser than baled hay and much denser than loose branches. More important, though, is that it can be blown into containers. Also, it can be heaped into stockpiles that won't rot, as long as they're covered. You wouldn't want to ship it hundreds of miles for further processing, but a regional co-op serving farms within a 40-mile radius would be easy.
Sounds very promising. Torrefaction and grinding of torrefied biomass are low tech. They can be done near the point of origin of the biomass. The result has a higher mass density, with a much higher volumetric energy density. The ground product is well suited for automated handling and transport. This overcomes one of the biggest economic hurdles for biomass.
@EP - The figure that I've heard for what biomass could supply is 25% of current motor fuels, without impinging heavily on food production. I.e., when restricted to being grown on marginal, non-irrigated lands. But I think that's for BTL processes in which the biomass provides all the energy for the conversion. Driving the conversion as you suggest -- using hydrogen to deoxygenate biomass -- would double that to 50%. @Kelly - The ScienceDaily article you asked about made a complete hash of the description of how the "heat storage" would work. I'd have to read the actual research paper to judge whether it has any real significance. I can pretty much guarantee, however, that it has no relevance to thermal splitting of water. 850 C would have been the temperature used to thoroughly dehydrate the zeolytes. There's no way that subsequent readsorbtion of water vapor could generate temperatures anywhere close to that.
It would have been nice had they bothered to mention its ISP. "High performance" isn't really very helpful.
The most striking military advantage of these kinds of technology would be the fast elimination of the need for oil. If crude becomes worthless and liquid fuel becomes abundant: .. Being possible and being economically feasible are quite different things. Liquid fuels synthesized from atmospheric CO2, water, and nuclear energy will work for the military in the near future because economic feasibility doesn't apply. Or at least not in the same way that it applies in the "real world". The rules are different when the recipients of federal largess are aerospace corporations and military contractors. It depends on how you do the logistics accounting, but by most reckonings, fuel for planes and vehicles deployed in Iraq and Afghanistan already costs the US in excess of $100 a gallon. So it's not hard for a nuclear fuel synthesis plant to come out looking like a bargain. Yet it's not the cost, but the qualitative difference in operational capabilities that will drive the program. Like the strategic differences that are enabled by nuclear submarines vs. the old diesel-electric variety. There is, however, some hope that at the end of this particular rainbow, we could find the sort of peace dividend that Alain's comment suggests. In the long term, there's no reason that "nuclear gasoline" won't become cheaper than crude oil. By analogy with the development of commercial jet transportation, the military will first develop and refine the technology, after which it will migrate into the commercial sector. That's assuming that we can avoid a collapse into war and chaos before then. Some days I'm hopeful, some days I despair.
I forgot to mention the most interesting and likely market-leading application of these chemical reactors. The military wants them. In the worst way. (And you can take "worst way" however you like.) DARPA has an RFP for studies toward development of modular nuclear reactors to drive synthesis of hydrocarbon fuels at military bases and on ships. They want high fuel burn-up, low waste production, and multiple years of low-maintenance operation before refueling. The idea is to cut the long umbilical cord that ties military operations to oil supplies. They want to ultimately produce all the jet fuel and diesel they need for fighting vehicles from just air, water, and nuclear energy. For better or worse, microchannel chemical reactors like those described in this posting will be key components in allowing them to achieve that.
Saying that biomass can't supply all our energy needs is accurate, but it misses the significance of the posted article. It not about biomass, it's about microchannel reactors for FT synthesis of fuel. The particular source of synthesis gas reported happens to be biomass, but the significance is in the compact size and demonstrated high productivity of the FT reactor. The usual approach to economic productivity in chemical synthesis plants is large size, to capture "economies of scale". That's OK for oil refineries or for large-scale FT synthesis from gasified coal (a la South Africa's Sasol), but for FT synthesis from gasified biomass, it sucks. For BTL synthesis, one needs small processing plants that can operate close to the source, reducing transport costs. Microchannel reactors are a good fit for that. They achieve economic productivity from mass production of small units. They achieve high product productivity through the favorable surface-to-volume ratios and superior heat transfer characteristics of small reaction channels. Regarding "1 litre of catalyst per .75Kg of production", there's an all to typical journalistic misstatement and misunderstanding of dimesions. It should really say something like ".75Kg of production per minute", or some other time period. I'm guessing it should be minutes, because .75Kg per second sounds too high, and .75Kg per hour sounds too low for production rate from that that amount of catalyst. In any case, it't production rate they should be talking about, not production. Catalysts -- by definition -- are not consumed in the chemical reactions they facilitate. But the more catalyst exposed to the reagents, the higher the production rate. They do degrade over time, however, and eventually need to be replaced. End of chemistry lesson.
critta writes: Oil is irreplaceable as a transport fuel. Energy used for uranium mining and transport and the massive construction requirements of nuclear power plants must come from somewhere. Actually, the construction requirements for nuclear power plants are not particularly massive, in relative terms. The concrete and steel requirements for even a conventional light water nuclear plant are roughly 10% of those of the largest and most efficient wind turbines, on the basis of kilowatt-hours delivered per year. The high cost of nuclear plants arises from labor and procedural issues that have little to do with the actual energy and material inputs to the project. There is a huge disparity between what it currently costs to build a nuclear plant and what it theoretically could (and arguably should) cost. That creates an enormus profit opportunity for any country that can develop the industrial infrastructure and technology to build nuclear plants at something closer to cost implied by their energy and material inputs. Guess what country is racing ahead to exploit that opportunity? Hint: it ain't the U.S. of A.
EP's comment above about crude-to-product yields is in line with my understanding as well. I also agree about relative easy of energy storage via CAES -- although the design that makes the most sense to me and would be most cost-effective seems to have eluded the established players. I may yet have to create a start-up... TXGeologist is right, though, that the way to view shale oil is not as an energy resource, but as a way to produce storable liquid fuel from surplus energy from other sources: off-peak nuclear or excess wind or solar. Its yield per kwHr, based on estimations I've seen from Shell, is about 3x higher than for fuel synthesized from CO2 and water. It makes sense to go that route, if you happen to believe that CO2-induced global warming is a giant hoax perpetuated through a conspiracy of government bureaucrats, climate scientists, and liberal "tree-hugger" environmentalists. Which perhaps TXGeologist does. I don't, however. For me it isn't a matter of blindly trusting NASA researchers and the IPCC. It's a matter of physics that I understand. So oil from shale *should* be taxed with its high carbon cost. If it is, it becomes non-competetive with fuel synthesized from water and biomass. The latter yields almost as much fuel per kwHr as high grade oil shale, and is carbon-neutral.
AFAIK, radon exposure in homes has nothing to do with any radon that might be present in NG. I suppose it could if the NG were being burned in room heaters that vent directly into the room, but those are against code in most places. Gas-fired central furnaces all vent to the outside. Radon typically diffuses into unsealded basements from from the soil, in areas where the soil is naturally high in uranium. The quantities are always minute, and become a problem only in tightly closed homes. The cures are to install a plastic diffusion barrier under the basement floor, and / or increase the air exchange rate for the home. The research cited in this article is interesting from a theoretical perspective, but I don't see it as comercially significant per se. There's no market for small-scale conversion of syngas to hydrogen. For large-scale production of hydrogen from coal or biomass, there's no way that a room-temperature enzyme-based reaction can begin to compete with the cost and throughput of a conventional water gas shift reactor. For small-scale production of hydrocarbons from water, CO2, and electricity -- which could have a potential market -- it's the reverse WSGR that's of interest. It would be cool to have a farm-scale unit that could produce diesel fuel from CO2, water, and solar electricity. But the reported mechanism won't help there.
Straight hydrazine is really, really nasty stuff. Used in the reaction control system of the space shuttle. After landing, the shuttle sits on the runway until a hazmat team has transferred any remaining hydrazine to safe storage and certified that there are no fumes wafting around. I don't know anything about hydrazine monohydrate. Perhaps the water molecule changes its properties enough to make it safe. But safety would be at the top of my issues list for anybody proposing to use it.