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Engineer-Poet
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Speaking of the Crescent Dunes restart, I found it extremely odd that it supposedly took months to refill the salt tank. It seems obvious to me that the way to go about it is to have a mixing/melting tank where hot salt from the collector is mixed with dry solid salt and pumped back into the collector at the cold-side temperature. Hot liquid salt would be piped into the tank as new salt was melted to replace it. That kind of process should have been able to refill the system over just a few sunny days. Did nobody even think of this?
The last time I looked at figures for Crescent Dunes, it was pretty much out of service. The claims about it differ. One site claims a 51.9% design capacity factor but penciling out the DOE numbers over 8766 hr/yr yields 50.0% spec. Using the latter figure plus the amount of the loan guarantee, the plant cost comes to $13,400 per average kW. That isn't particularly cheap, and it's far from the first of its kind (unlike Vogtle 3&4). What sort of subsidies have been granted for the SA project? Since these plants are only feasible in deserts at low latitudes, they cannot be generalized to the entire world. Most electricity is consumed at upwards of 40° from the equator. Even if it works, Crescent Dunes must be considered more of a curiosity than a case study for all or even most economies.
Baseload CSP plants? None exist in the USA. 40% of the way to $0.05/kWh assumes it's $0.10/kWh today, which is half of the only figure I can find for what Ivanpah is paid. Trying to use CSP on the surface of a planet is a mistake.
The USA consumes on the order of 600 million metric tons (152 billion gallons) of gasoline per year. 1 kg H2 has energy roughly equivalent to 1 gallon of gasoline, so less than 7% equivalent of gasoline consumption. There is also no network to distribute hydrogen beyond Gulf-coast refineries, and all of that hydrogen is produced by reforming hydrocarbons. Electricity is already everywhere. Why is it so hard to keep "greens" from being distracted by the shiny hypedrogen bauble dangled by the oil companies?
If QC expects to reach even 300k EVs by 2026, it will need a lot more than 1600 fast chargers by 2028; it should have probably 6k along major travel routes. It will need vastly more slow (Level 2 and even Level 1) chargers than that; it will need on the order of ½ to 2 public/work chargers per vehicle, placed where people go. The way to promote electric transport is to make it effortless. EVs should find what they need wherever they go. Build it and they will come.
It takes 4 moles of H2 plus 1 mole CO2 to make 1 mole CH4. 4 moles H2 is 1144 kJ HHV. 1 mole CH4 is 891 kJ HHV. There are a LOT of losses in methanation, and this begs the question: what supplies your CO2, and is it storable if you don't have the H2 supply to use it as it's produced? The "green methane" scheme is a scam.
Petcoke is hard to even give away. A refinery south of Detroit is under fire for leaving heaps of it out in the open where they generate toxic dust. It's just a short barge trip to the coal-fired plants in Monroe, but those plants will not burn the petcoke to help get rid of it. Apparently they cannot meet their emissions limits if they use it as fuel.
Setting a course which can only get to 10% no-carbon is aiming for failure. We need to find a course which can get to 100% and beyond, and then stick to it. Yes, I have a scheme for doing this. I'm in the patent process right now.
I just checked out the info on one of the more likely sources of "renewable" fuel, landfill gas. Cedar Hills Regional Landfill produces just 15.4 million therms of LFG per year (a therm is 100,000 BTU). At roughly 140,000 BTU/gallon, that's equivalent to just 11 million gallons of jet fuel even before losses in conversion. Conclusion: using current approaches, getting to 10% renewable jet is going to be a MAJOR problem. Getting to 50% is likely impossible.
I looked at that, and realized that electric flight is just the thing for those short hops of a few miles. But if there are going to be a lot of those things in the air, automated traffic control is going to become a major issue very fast. Things will happen too quickly for human pilots. With automated control, hacking becomes a threat.
The cost breakdown for the different phases is not given. $4.2 million for 2 chargers each at 13 lots is very steep (about the cost of a Supercharger), so it is likely that that's the price tag for the entire effort of which the Level 2's are only a small part. Guessing $10k apiece (installed) for one dual-head Chargepoint unit per lot, that's just $130k of the total. The number of Level 3 chargers at those 9 service areas is not given. That's an annoying omission. One would hope it would be at least 2 chargers in each direction, but without info I'm only guessing. Guessing $4.07 million for 36 units is just over $110k per, or on the order of a Supercharger. Maybe it's more than 4 stations per. The price tag would appear to cover it. This is real progress.
Elimination of carbon electrodes also means elimination of perfluoromethane (CF4) emissions from the process. As it has a GWP of 6500 and an atmospheric lifespan of 50,000 years, this is a huge improvement.
It's got nothing to do with electric trucks. Per this GCC post last month electric drayage trucks ALREADY appear to be in use at the Port of Los Angeles. If you've already got something besides the internal combustion engine, buying more internal combustion engines isn't part of moving away from them.
Yes, it's true that a 100 MWh / 400 MW battery system can ramp a lot faster than any gas turbine. It's also true that demanding rated output from said battery system depletes it in 15 minutes at most. When that 15 minutes is up, there better be a gas turbine or something to take up the load. Barring failures and overhaul intervals, the gas turbine can run as long as it has fuel. If you're going to use batteries to manage the grid, they're probably best employed in double-duty applications like PEVs. It only takes about 60,000 active EV chargers at 6.6 kW apiece to provide the demand-side management load of the stationary battery (2x as many to provide the same peak-to-peak load variation, assuming no V2G capability). Tesla alone is shipping 30k vehicles per quarter. The AC Propulsion vision of using electric vehicles to provide most grid regulation functions ought to have been here already.
The cleanup and transport required for "RNG" (most likely landfill gas) at the port makes it a loser energy-wise compared to using said gas to replace natural gas near the source. Generating electric power at the landfill, then wheeling the power to the port to run electric drayage trucks, probably beats the RNG trucks for efficiency and certainly whips them for noise and emissions.
The real issue here probably isn't liquids, coal or biomass. More likely than not, it's petcoke (the residue left from "coking" heavy oils to make lighter, usable fractions from unsalable heavy residues). Petcoke is filthy, to the point where coal-fired power plants just miles from refineries won't or can't burn the stuff (emissions regulations). Gasifiers which can handle coal can also use petcoke (as the Wabash River Repowering Project proved) and of course they could take the heavy residual oils and gasify them directly, avoiding the coker altogether. They can turn this stream into syngas, which has a multitude of uses. Syngas contains a great deal of hydrogen, which is required for hydrocrackers and desulfurization units. Carbon monoxide can be water-gas shifted to hydrogen and CO2, or burned for process heat. As emission limits tighten, it seems to me that gasification has a bright future.
Since carbon is the limiting factor, the figure of merit has to be useful energy out per unit carbon in. Naptha is way down the list. Naptha made via autothermal gasification of biomass... way, WAY down the list!
SJC, if you'd bother to do the math you'd easily confirm that there is nowhere near enough biomass to "provide all the fuel". Not even the "Billion-Ton Vision" papers say biomass can provide it all. They don't even say it can provide a majority of gasoline. The fact of the matter is that there isn't enough biomass for biofuels to do the heavy lifting. Something else has to take that role. Biofuels can take the niche applications where the heavy-lifters don't work well, like aircraft and off-road.
The figures pencil out to about 110 gallons per ton. At perhaps 3 kg of fuel per gallon, this is a mass-conversion ratio of around 30-35%. Even if the products are pure hydrocarbons, that still means lots of carbon loss in the process (biomass feedstocks are 40-45% carbon by dry mass, depending whether they're woody or herbaceous). The high heat release in FT synthesis means energy is being thrown away. That should be suspect. Unless the application requires high energy density or other properties, hydrocarbons are probably not a good choice of product. We need to be aiming for commodity products which (a) contain as much of the feedstock carbon as possible, and (b) embody the most energy per unit carbon. Right now the winner is methanol, at 726 kJ/mol carbon. Ethanol is more than 10% worse, and F-T hydrocarbons are way worse than EtOH.
Without the "charged by electricity alone" restriction, my calculations suggest that the efficiency of electric_out/electric_in could be around 120%, with storability measured in months if not years.
"Charged by electricity alone." There's the box you're not allowed to think outside of. Such a waste.
I'm disappointed that there aren't more multi-purpose options in the LDV segment. Take the Ford Energi models. Given the specs on the battery and whatnot, it shouldn't be all that hard to connect the inverters for the direct-drive motor-generator to an external outlet for at least 10 kW of external power (IIUC, MG1 is rated at 68 kW). The engine and MG2 would suffice to keep the traction battery charged. This would be an EXTREMELY useful combination, requiring only some transfer switches and an outlet to power an entire job site, but... you can't buy a vehicle with it.
Now imagine what it will be like if the conspiracy to shut down Diablo Canyon isn't foiled in the courts.
So interesting that VW sells cars that run on e-methane (which is interchangeable with fossil methane), but not ammonia (which can be produced from electricity, water and air alone). I have not run the numbers but I bet that liquid ammonia has a much higher energy density than CNG. Given that the unburned methane has a vastly higher GHG potential than rapidly-oxidized ammonia, the push for CNG cars over ammonia fuel is exposed as greenwashing.