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Engineer-Poet
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Aerodynamics, I bet. The profile is awfully Prius-like.
You wouldn't use AdBlue on a ship; they're big enough to use anhydrous ammonia.
As I recall, pyrolysis oil is about 50% water by weight. One of the first steps in this process is going to be distillation to separate the water from the useful feedstock.
Looks nice, but nothing on MSRP.
Does cast metal have lower resistance than drawn or rolled metal? I know the grain structures can be radically different and in rolled metal it is anisotropic.
Square wire is already in use in some motors, precisely to improve the packing factor. It's been the subject of previous GCC posts.
Less than 5% out of 20 TWh of waste heat is less than 1 TWh of product. Compared to 140 TWh of generation, this is a rounding error. Do learn to do math, SJC. And no, correcting and admonishing you is NOT insulting you. If you take it as an insult, it only proves that you do not have the intellect to grasp what you're seeing even AFTER it is explained to you. Put down the ego and step away.
One of the ways carmakers have made A/C evaporators is by vacuum induction brazing. They're old pros at this stuff. Sweat-soldering of joints on the production line doesn't sound like something that would slow them down much; just pre-solder the mating surfaces to an interference fit, squeeze together using some kind of tool during installation, and then heat the joint to seal it. If your A/C compressor is electric, but it still has a shaft seal, it sounds very much like the mfgr is Doing It Wrong.
700 kWh/kg is a great deal of energy; it corresponds to a heat-to-hydrogen efficiency of less than 5%. As a way to make use of waste heat it's not at all bad, but we're not going to run society on it.
Roger, I asked you about EROEI. You ignored it. I asked you about the ability of appliances to cope with radical changes in fuel characteristics. You ignored that too, and the question about what kind of domestic FC can switch seamlessly from NG to H2. I asked you about energy capacity of reservoirs when methane is replaced with H2. You went on about theoretical flow capacity in pipelines assuming near-sonic gas speeds. Well, I went and looked up some stuff about pipeline flow rates. I couldn't find anything which stated flow speeds directly or allow me to calculate them, but I did find a mention of Reynolds numbers peaking out at about 4 million. 4 million is a VERY long way from sonic speeds. In other words, the stuff you posted is wrong, and it only pertains to the pipeline part anyway. Are you trying to baffle me with BS? Because you know I do not suffer fools gladly.
Looks like the Tesla Model 3 AWD performance will out-accelerate the Mach E GT, at a lower sticker price. Maybe there are dedicated Ford fans who'll buy this thing, but after giving it a look I'm definitely not in the market.
Ye gods, Roger. Talk about snake oil! Produce Hydrogen during solar peak, at 82% efficiency LHV and as much as 95% efficient HHV, by using Sunfire or H2Pro electrolysis techs.... In the evening, fire up the residential fuel cells for electricity while the waste heat is used for making hot water for bathing, dish washing and laundry. At 95%-efficient electrolysis, calculated based on HHV, the round trip efficiency can be above 90% Let's see some evidence for these efficiency figures, and the engineering practicality of achieving them. Note that the EROEI of PV is around 6.8 before any investment and losses in storage. That's well below the minimum required to run our society. Nobody is running a PV plant on PV panels. Store the H2 within the local residential piping system for natural gas, which can tolerate even 100% H2. Seasonal quantity of H2 can be stored in existing underground natural gas storage system.How do you expect all the gas appliances to cope with wild swings from 1036 BTU/ft³ for NG down to 275 BTU/ft³ for H2?How do you expect the same to cope with the wild swings in flame speed?What kind of FC are you talking about here? PEM FCs can't handle methane.You need 3.8 times as much volume of H2 to carry the same energy as NG. Pipelines are often running at maximum capacity already; are you going to magically expand them 4-fold?There are bacteria which consume H2 to metabolize sulfur and turn it into H2S. Are your NG reservoirs free of sulfur-bearing rocks?Of those which are, you're going to be able to store about 1/4 of the energy as H2 compared to CH4. How's that going to work out?There are more essential questions, but that should temper your enthusiasm. I had thought you were wiser than that.
The casing still has joints and fasteners, meaning gaskets which can leak. The next step is to put the compressor in a hermetically sealed, welded can like most electric A/C hardware uses. The electronics can be integrated either inside or outside the hermetic seal.
More and more SiC news. Big changes are afoot.
Your mass solar farm is in darkness when your demand peak hits, Roger. What are you going to do about that?
I considered that most gas stations could use the water they already have supplied, and solar power w/cheap night electric, to create and store the hydrogen for distribution. Ah, the "let's NOT SHIP HYDROGEN AT ALL" troll shows up. Okay, troll, let's see you square this with the need to store MONTHS of production to deal with seasonal energy deficits in a "renewable economy". Hydrogen is pretty rarefied stuff. Even when you spend the energy to liquefy it you only get to store 8.4 MJ per liter of liquid (120 MJ/kg times density of 0.07); gasoline holds about 32 MJ/liter. Then you have to keep spending energy to keep it a liquid. You think you're going to do this at every corner station? Using the existing refueling/distribution infrastructure along highways that pump gas/diesel is the only practical way I have seen to refill the vehicles without a very heavy infrastructure investment. That is exactly what the oil companies are counting on. Hydrogen is their way of owning you forever.
This, from an organization that didn't allow fuel injection until 2011 and still doesn't allow turbocharged engines despite them being ubiquitous.
That is not the DOE's take on the costs of hydrogen, nor that of energy authorities in Europe, where the inherent surpluses of a high proportion of renewables in the grid are to be used. I was unable to find anything about the source the DOE expects to use for this hydrogen. Of course, cheap NG + SMR yields cheap H2. We've seen on this site processes which take methane from the pipeline, add water, and reform it to H2... with no obvious disposal for the CO2 other than dumping in the atmosphere. This is not a solution. Europe is smoking something very, very strong. The round-trip losses for electrolysis and fuel cells are over 50% and probably closer to 60%. That does not include the unavoidable losses in liquefaction for short-term storage and conversion to room-temperature liquids like NH3 for long-term storage, nor the costs in infrastructure, O&M and interest thereof. Then there's the CO2 emissions involved in making the concrete and steel for all of that. They'll go broke. Proponents of BEV only approaches Which I am not. I suspect that the optimum spot for the next several decades will be PHEVs. It is very expensive to make batteries a 100% solution; it is much cheaper to make batteries a 70% solution and do the remaining 30% with some kind of renewable liquid fuel. production of hydrogen for steel making, ships, trains and trams together with ammonia production will drive costs at the bulk level down, and there is no way at all that batteres can provide solutions to those industries Batteries aren't a solution for on-grid uses lasting more than minutes. Heat storage in e.g. solar salt is very cheap and can store heat for hours or days. Even dumping electricity straight to electric heaters in salt tanks to make steam later, you can get round-trip efficiencies close to hydrogen. This requires no fancy catalysts and lasts for years with minimal degradation. The "renewables" that that the scammers running Europe propose to rely on can go off-line for weeks at a time, with not enough time to re-fill storage before the next outage. Basically, it involves putting the economy and millions of lives under a Sword of Damocles which is guaranteed to fall, soon. That leaves transport to the fuel station as the remaining cost.Which would require a whole new pipeline system to make practical. Trying to repurpose the NG system would fail, as NG has about 3x the energy density and would be limited to about 1/3 the total energy carried. That's an instant failure; it can't even serve current demand, let alone vehicles. That leaves trucking the H2. As luck would have it, I stopped by a gas station this evening. A tanker truck was refilling its underground tanks. I asked the driver how much it carried, and he said 13,000 gallons. All up, the rig weighed about 120,000 lbs. Figure 95,000 of that is the trailer itself. At 7% H2 by weight, it would carry 3016 gallons-equivalent of H2. Even if one gge of H2 does the work of 2 gallons of gasoline, you'd still need TWICE as many trucks on the road to carry the fuel. The last option is to reform methane to H2 on the spot. This can likely be done with the existing NG pipeline system, because 1 kg of methane at 50 MJ LHV, plus water, plus electricity, can make 0.5 kg of H2 at 120 MJ/kg = 60 MJ of useful energy. It also makes 2.75 kg of CO2 per kg CH4, which you'd either have to truck to some disposal site or just vent. Do you begin to understand why I call it hypedrogen?
It doesn't matter how good/cheap your FCs are if you can't afford the fuel for them. The avowed goal is to operate on "renewable" energy, but the end-to-end losses of wind and PV to hydrogen back to electricity are enormous and multiply the cost. The cost and losses of storage have to be added to this, because in an all-RE system you have no stockpiles of fossil fuels to serve as your buffer against lulls in supply and surges in demand. These can be reduced somewhat, but thermodynamic limits mean that they cannot be reduced enough. That cuts into the already-low EROEI of "renewables" and makes it impossible to run an industrial society on them. The upshot is that the "hydrogen economy" will be permanently tied to steam-reformed methane and gasified coal. It's a dead end, leading to a dead planet.
Both Toyota and Hyundai are putting in the capacity right now to ramp PEM fuel cells ten fold. I went digging for Mirai sales figures. Apparently only about 6000 had been made as of 2018, just 3000 in 2018. You can't even use a Mirai in most of the USA because you can't get fuel; Tesla ALONE is selling 90,000+ vehicles per quarter and can use literally any electric outlet. Hydrogen production and infrastructure reduces costs throughout the value chain And the only realistically cheap sources are natural gas... and coal. Making H2 from "renewables" multiplies the cost several-fold over direct use of the electricity. But what do Toyota and Hyundai know about drive trains for cars compared to internet bloggers? Internet bloggers read more than just marketing hype. 6000 Mirais stepping up to 30,000 per year, versus 400,000 Leafs as of March 2019. It is obvious where the infrastructure advantage and momentum is. If incentives and subsidies were equalized tomorrow, hydrogen vehicle fuel would disappear and the Mirai with it. Hydrogen just plain costs too much, and on top of that it's dangerous.
Paraphrasing: back then, rising prices seemed to have no top and lenders handed out cash like candy figuring that equity would appear like magic to put the paper in the black. A lot of that cash probably went into vehicles. And then came the top, and it all evaporated.
FFS, I cannot get a simple comment about 2007 financial shenanigans past the filters today.
Yes, I suppose you could cover a square kilometer of farm land with PV panels, and produce perhaps 150 MW(peak) at noon on your best sunny day given the required spacing and tilt, and a 20% capacity factor if you've picked your site really well. Or you could take that same square kilometer and generate at least 2200 MW(e) 93% of the time, with no emissions save maybe some water vapor. That would leave roughly 66 square kilometers you would NOT have to cover with PV panels, and a whole lot of batteries you wouldn't have to buy either. What to choose, what to choose?
We've really got a division between the hypedrogen hordes on one side, and every other kind of fuel cell on the other side. That other side includes solid-oxide and methanol FCs. Remember that when we were right on the edge of getting our 80-MPG PNGV cars and achieving oil independence again by 2010, oil-financed GWB killed the program (which set us back more than 20 years) and gave us the hypedrogen Freedom Car program instead. Notice what we STILL don't have in any kind of quantity? And the few we do have arefueled at central stations,mostly from hydrogen made from natural gas.It is right back in the pocket of the oilco's, controlling everything. A PHEV with a methanol FC gives the consumer far more choices about what to run on and where to get it. It's the mandatory reliance on hydrogen, controlled by a few companies, which is the trouble with the "clean" FC model.
Okay, this thing generates H+ ions at the positive electrode (OER side) and turns H+ into H2 at the negative electrode (HER side). Does it evolve CO2 at the oxygen side, e.g. turning carbonate ion into CO2 and oxygen? A lot of the notions out there require CO2 for various functions and it would be good to know if cells based on these catalysts can do that too.