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Engineer-Poet
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Alan Drake supplied me some figures for the cost of rail electrification, which I posted at The Ergosphere. The upside of H2FC trains is that the rolling stock is not subject to property taxes of the localities on the route.
HEVs using batteries batteries with a substantial SOC window, plus a charger, become limited-range PHEVs as well as a resource for grid regulation. If you have 500 Wh of charge to take on, and an hour to do it, you can switch the charger on and off to soak up temporary surpluses in power on the grid.
There's already a dual-voltage "convenience cord" on the market, from whom I don't recall. It's what should have shipped with every EV/PHEV out there, but didn't.
As I recall, the Prius battery was once limited to about 15 kW. Double that, as a reasonable first step. 30 kW of power at 5 kW/kg requires just 6 kg of cells, or 24-25 of these cells at 240g/ea. Alternatively, go for a reasonable battery mass of 20 kg, achieving 100 kW of peak power. That puts the stock Prius to shame. If these cells don't cost an arm and a leg, they are going to make stop/start and hybrids a lot more smooth, powerful and successful in the marketplace. At 80 Wh/kg, a 20 kg battery holds 1.6 kWh. If the SOC range isn't constrained too much, this allows significant PHEV capability (several miles) at the cost of a charger. With the charging connection comes the capability for e.g. cabin pre-conditioning, so this is a very worthwhile undertaking.
DME is energetically "downhill" from MeOH, which is a superior fuel both by energy density in the tank and power density in the engine. Further, DME can be made on the spot from MeOH; there's no need to carry it. Finally, MeOH can be thermo-catalytically reformed to CO and H2, which has more chemical energy than the alcohol and also a higher flame speed; this is a possibility for recycling exhaust thermal energy back to the engine. DME's best raison d'etre is as aerosol propellant. As a way of eliminating CH4 leakage in the vehicle fueling process, it has no advantage over MeOH.
Many countries will soon have 100+ H2 stations. Yes, 2 per US state is going to make life just as pleasant for the FCEV's driver as the gasser's. Not. I found an estimate that there are ~150,000 filling stations in the USA. A reasonable lower limit for full coverage for a new fuel like H2 is 10% of that, or 15,000. Meanwhile almost everyone already has electricity at their house.
I look at these numbers like "60 stations in the USA" and think "what consumer in their right mind would buy one of these things? You can barely go anywhere."
Jet-A is a lot cheaper than aviation gasoline. Avgas is a tiny niche product, Jet-A is a substantial fraction of all petroleum use.
Good point. Gold is about 1/3 as abundant as Pt, so unless the alloy nanoparticles are far more economical with it then this is pretty much a nothingburger.
CNG has roughly 3x the energy density of H2 at the same pressure, and much better than that as liquid. I'm agnostic on the issue of hydrogen per se. You can get 17 wt% storage by using ammonia; the sodium-amide process converts it to gases at a small energy cost. Burn it in an engine until the FC makes it, fine; $30/kW has been a fait accompli for years. What gets me is the upstream end, where un-sequestered NG and even gasified coal will have a large cost advantage over anything electrolytic. That is what we have to get rid of, preferably by eliminating its market. HFCs don't do that.
Taking your bait... this catalyst solves (sort of) the problem of capital cost in the electrolyzer's catalyst. It still leaves the other 4 required miracles wanting, not the least the cost of the energy (electric) required to drive it.
It appears that this is a way to get a substantial fraction of higher-value products from low-value fuels. The combustion of "residue" would appear to be not much different from the same with coal, and perhaps better if the water content was reduced (less energy lost as latent heat). Given Japan's difficult situation with fuels and balance of trade, this could work out well for them... so long as they continue to ignore their Kyoto duties!
Let's see... 50 gallons per ton. At roughly 1 ton MSW per capita per year in the USA, that would produce roughly 15 billion gallons/year of jet fuel. As I recall, that is roughly in line with actual consumption.
Everything old is new again. Aside from freezing issues, perhaps this is superior to some of the "octane on demand" fuel-fractionation schemes out there. The price is right, the infrastructure is pretty much there already, and it's not like we lack experience with the stuff.
What is the function of an intercooler, if there is only one compression stage? There are 2 compression stages. The intercooler reduces the back-work from the second stage, and reduces the compressor outlet temperature so that more energy is recovered in the recuperator. Has WrightSpeed considered adding an Organic Rankine Cycle Waste Heat Recovery (WHR) System? It's probably not a good fit for the light/cheap goals of the exercise, and additional heat recovery would probably be done better by adding another stage of compression and intercooling so that the recuperator has an even lower inlet temperature to work with and can recover more exhaust heat. You raise a point, though. I've wondered this about the intercooled GE LM100 gas turbine. The intercooler options include air-to-water and air-to-air... but the public GE documents don't have anything on BTU output, outlet temperature or anything else that would indicate suitability for heat recovery.
The Capstone units use air bearings. Seems hard to wear them out in operation, though the number of start-stop cycles would appear to be an issue.
Peskanov, the part of the Nature paper outside the paywall says 70 mAh/g and a nominal 2 volts or so. That's about 140 Wh/kg. If you have access to the full paper, please quote the figures which show how that is in error.
Arguing that the electron coming from my solar array needs to go right into my battery to be legitimate is a bit of disinformation. No one in the business looks at it that way. ECI, that electron needs to go right into something. If nothing is available, the power is lost. The claim has been that EVs are key to balancing the ups and downs of wind/PV generation versus demand. If they're not actually plugged in, any claim relying on it is bogus. Charging one battery so it can later charge another battery is getting Rube Goldbergian.
This is how it is almost everywhere. I'm aware of pumped-storage systems which use overnight excess power (there's one maybe 100 miles from me), and a CAES unit somewhere down in Alabama or the like, but that power is sold. I'm aware of nobody giving it away, especially not during their peaks of production. wind turbines are often shut down because of excess. Yes, about that. Excess wind power could easily substitute for fuel in industrial process heat. Iowa has a bunch of ethanol operations, which all use heat to mash the grain and distill the product. Excess wind power could be dumped to heaters there, substituting for natural gas and avoiding the need for curtailment. Why isn't this happening? solar and wind will become cheaper and cheaper for years to come It doesn't matter how cheaply you can make something if you get zero or negative value from it. Schalk Cloete has calculated that the value of intermittent RE falls to zero at about 27% penetration on the grid. After that, it's negative due to the costs of integration. I agree with more nuclear, but you can't drive a car on uranium or thorium. 27% of the electric power generated in my state is nuclear, and about 2/3 of my driving is powered by electricity. I am driving my car on uranium, about 1 mile out of 5. If I lived in Ontario that figure would be closer to 1 out of 2.
The cost of the electricity is almost irrelevant, because it is only excess electricity that will be used. If you assume that people will invest money to produce very much electricity they can't use and just give it away, you're not dealing well with reality. in the real world there will be many ICE's around for decades I rather doubt it. How long did it take steam cars to disappear once the ICEV won the race for reliability and convenience? Much less than 20 years, I bet. If we get the 140 Wh/kg aluminum ion battery that charges in 1 minute, I expect that it will take over laptops and smaller devices in 2 years (imagine getting 2 hours of laptop power in 6 minutes), completely take over hybrid cars in the next model cycle (3 years or less) and EVs in about the same amount of time. Once an EV can charge in 10 minutes or less there will be no perceived advantage to ICEVs and the market for them will collapse. The question is where should the fuel we burn so far come from Germany has ocean front and can harvest uranium from seawater as easily as anyone else. Nuclear power can supply all the energy Germany needs, without relying on anyone or anything else.
It would be worthwhile to compare the fuel economy of the gasoline hybrid with the diesel on the same cycles. Gasoline is considerably cheaper than diesel in the USA, and getting toward parity in fuel economy would swing the economics strongly in favor of the hybrid.
Not one single word about COST. I'll bet dollars to doughnuts that if the public saw just what the electric power input alone for a liter of this stuff cost at wind or solar FIT rates, the Energiewende would be history after the very next election.
The ForTwo is an answer to parking problems. Its boxy shape is lousy for fuel economy, and not surprisingly my nearby eco-conscious city has swarms of Priuses but maybe a single ForTwo to be seen.
Certainly the US, following California, is rather isolated in its selection of BEVs and FCEVs in preference to PHEVs as the standard to push. That goes way, way back. The original CA emissions regulations of the 70's would have been much easier to meet with PHEV technology (eliminating many issues of throttle transients would have been a huge help), but it never got a foot in the door.