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You can rest assured that a 48 V, 500 Wh battery is going to be a lot cheaper than a ~300 V, 1.5 kWh regular hybrid battery. I'm wondering just how much performance that little motor and battery would provide, though. Creeping in parking lots and heavy traffic is one thing, but you'd really like to be able to soak up a lot of energy quickly when braking from speed. 12 kW just isn't that much. Is it going to be worth the electronics required to drive it? I must admit to being spoiled. I just braked from 55 MPH down to 15 MPH in about ¼ mile using nothing more than regeneration. Figuring 1600 kg of vehicle and 22 seconds, that's about 450 kJ in 22 sec or a bit over 20 kW with a peak maybe 2x that.
Were you incognizant of the PNGV efforts, which were so close to realization and then so quickly abandoned in lieu of hydrogen "Freedom Car" programs after the election of Da Shrub? Do you not realize that the hybrid and PHEV offerings of Honda, Toyota and other companies owe more to PNGV than anything later? Such ahistorical blindness is what happens when you prefer ideology to anything resembling fact.
EP you gave me a good chuckle. You're outrageous. My "outrageous" positions have a way of becoming conventional wisdom over time. Truth eventually wins out over propaganda and wishful thinking. You can't make a case for car companies and government investing in fuel cell technology if the battery car is the end all be all as you attempt to spin. I make the case that the auto companies are paid $tens of millions/year to build fuel-cell cars (including the government-paid H2 fueling stations) so of course they're going to do what it takes to get that money.
The economic vitality of both vehicles is ytbd. That is why so much R&D investment. Hydrogen has very attractive attributes that surpass what is possible with batteries. "Attractive" attributes, like cost in excess of $2 million per fueling station which can handle perhaps a dozen vehicles per day. Meanwhile, $300k worth of Supercharger can field 4-6 vehicles every 30 minutes, and at least 50% of the population has everything they need to do overnight charging at home: an electric outlet in reach of the vehicle. The grid is fragile and expensive. It's just the nature of the beast. Our grid is horribly expensive to update and will slowly progress. Are you proposing we get rid of it so we can stop paying for it? No? Then shut up. Are those costs going to be increased by BEVs any time soon? No. Using BEVs as schedulable demand can even lower grid costs by e.g. substituting for spinning reserve. Read the current trend of warehouse fork lifts. No better place for battery power. Forklifts are intended to run an entire workday, often 2 and sometimes 3 shifts. Swapping out batteries to charge is time-consuming and dangerous. The amount of energy is small and its cost is negligible, so HFCs are a good fit. Road vehicles have radically different needs. The industry is in the throws of converting to fuel cell for a whole host of advantages.The word is "throes", and it's ONE advantage: faster fueling time and elimination of the battery charging/maintenance bay.
The major reason to be concerned about hypedrogen is to use it as a proposed way of papering over the unreliability of "renewable" energy sources (specifically wind and solar). In reality, things will continue on the course of using fossil fuels as a "bridge" until ruinables + hypedrogen are cheap enough to eliminate them. Which will never happen. Meanwhile, the press to eliminate emissions-free 24/7 energy (nuclear) will continue behind the scenes.
Quoth SJC: You can make hydrogen at a fueling station using renewable power contracts then sell the oxygen to reduce costs. When oxygen is produced on the scale required to fuel even 20 million FCEVs using electrolysis, it will flood the market and the price will fall to the cost of compression and transportation. As of 2006, the world market for oxygen was about 1.2 million tons per day. A large part of this is required by steel producers at specific points of demand and shipping becomes the major factor. Producing 8 kg of O2 per kg H2, your 5 kg fillup in a Mirai will generate 40 kg of oxygen. Filling 1/wk per vehicle is 6 kgO2/day, so just one USA-full of H2FCEVs would satisfy 100% of world oxygen demand by itself. Doing the math helps keep you from looking like a fool. I highly recommend it.
The farce is strong in this one. It seems you provided much info on why the grid has poor efficiency. Honestly. You can look at figures showing that a grid-based BEV system achieves nearly twice the efficiency of a hydrogen FCEV system running off reformed methane (which doesn't include any overhead for carbon capture, BTW) and spout a completely opposite assertion? You really ARE nuts. You have to transport fuel, steam turbines low efficiency, line loss, no power storage so electric system must always operate out of efficiency zone, battery losses. SMR has to transport fuel too, and electricity travels very well. Ultrasupercritical steam turbines hit 45% even without GT topping cycles. The grid doesn't use batteries, and BEVs are quite acceptable today. Also, the grid is incredibly expensive and delicate as compared to pipelines. Expensive? Not at less than 15¢/kWh, and there is no substitute. Delicate? Hardly; you can run an AC grid using 19th-century technology, you just need bigger operating margins than with good SCADA. Pipeline is incredible efficient for transport of high btu fuel, natural cost free storage, and pressure recuperators to lower pumping costs. Pipelines are more delicate than the grid. During the Enron-engineered blackouts in California, gas deliveries to critical generating plants was slowed down. The compressors on the natural gas pipelines are electric, and when they got blacked out the whole system took a hit. Know what kept running flat-out? Diablo Canyon and San Onofre. No fuel delivery problems there! Once generating hydrogen it makes more sense to just utilize the gas as an portable energy fuel. Easy to amass hydrogen for strategic defense. How would once accumulate electricity? Seasonal variations no problem just pump up more storage. So you're blythely assuming the feasibility of H2 electrolysis on the scale of many, many GW, the availability of suitable storage (you might want to look at Aliso canyon again and ponder a leak of explosive gas on that scale) and other things which are currently operating at industrial scale... Precisely nowhere. You would bet civilization and the lives of millions on something that has literally never been tested in practice. That's not merely nuts; if you were in any position of authority I would have to call for you to be removed as a danger to the public. A couple gallons of water suffice for hydrogen car refueling. Hydrogen from electrolysis is 3x or more the cost of hydrogen from SMR. You can talk about "renewable hydrogen" all you want, the truth is that it's part of a bait-and-switch. The oil companies are gas companies now and they want to own the energy system just like they do now. Batteries won't let them. Hypedrogen does. Hydrogen generation isn't really a problem given all the possible channels of improvement. You're going to need plenty of improvements, seeing as electrolysis is competitive exactly NOWHERE. Again, fruitless to attempt to compare or deduce the future. You just assumed that the grid and BEVs will not improve and make hypedrogen pointless. Rather, keep hypedrogen pointless. It is not remotely competitive today. Absolutely, totally nuts. Most enthusiasts love electric drive, not the battery. The battery in my PHEV is charging right now. I LOVE the battery. I haven't had to fill the car's tank since a long trip in January. I would love it more if it held more juice and took up less room, but the perfect is the enemy of the good enough.
Trees, are you nuts? [hypedrogen] is a magnificent energy carrier An energy carrier so sucky, the Department of Energy has a long-standing goal of improving the weight of the systems to carry it to less than 18 times that of their contents... and still hasn't succeeded. as compared to hard wired grid with poor efficiency and poor energy storage ability. The US grid delivers 93% of the energy that goes in from generators to consumers. Combined-cycle gas turbines are now up to 62% efficiency, so pipeline-to-consumer energy efficiency can be as high as 57.7%. Batteries are as good as 90%. Steam methane reforming alone has losses of 32%, and that includes co-products with hydrogen. Then you've got the energy required to transport hydrogen (probably 20% given the high weight of tankage), compression work for fueling stations (at least 5%) and the losses in the fuel cell (40%) and you're down to 31% from pipeline to the terminals. The efficiency of the hydrogen system is about as good as, if not inferior to, compressed natural gas engines. Hydrogen cars are the taxpayer's subsidy to try to keep the oil companies relevant, when they need to die.
No word on price. Obviously, this means it is not competitive in the least.
OF COURSE Big Oil is going to bet on hydrogen. It is the last gasp of relevance it has for ground transportation. Even PHEVs push the majority of energy through electrons at home, not fluids at stations... and electrons have no loyalty to hydrocarbons. A PHEV architecture which produces most of its energy via electrons and the bulk of the rest through waste-derived biofuels would leave Big Oil in the lurch. Wouldn't that be great?!
Tesla was going to go with a 2-speed transmission but found it too troublesome, so they just accepted the range/performance/NVH hit. Maybe these folks can succeed where Musk failed.
PHEV drivetrains require far less size and weight of battery packs, but can still displace very large amounts of liquid fuels with electricity. 50 miles of electric range is more than enough to replace between 65 and 80 percent of liquid fuel demand.
Ammonia is created at body temperature by biological processes. The Haber process needs high pressure, but high temperatures favor cracking to H2. The moderate temperatures it uses are required to make the reaction run acceptably fast; lower temps have a more favorable equilibrium but go way too slowly to be economical.
It took a bunch of digging to find the data sheet on this: http://www.transphormusa.com/document/650v-aec-q101-cascode-gan-fet-tph3205wsbqa/ Max drain-source voltage is 650 V continuous. This isn't even twice the peak-to-peak voltage of a 240 VAC line, so either two of them will be required in series (doubling resistance losses) or the charger and its related systems will have to "float" rather than being grounded.
No link except to the company web site? Not even a press release? I'm wondering exactly HOW alternator failures become a thing of the past. Even flywheel-integrated permanent magnet alternators can have electronics failures.
The open binding sites on the catalyst have a lot of binding energy. If they're open when the catalyst is cooled, the introduction of ammonia and oxygen releases a great deal of energy and heats the catalyst immediately. This jump-starts the reaction of oxygen and hydrogen to water (also highly exothermic) and presumably the various products do not bind well and release easily to repeat the cycle. The press release doesn't give a chemical efficiency or yield for hydrogen. Apparently the catalyst needs to be both free of ammonia and dry to cold-start itself. This system may be usable alone, or as an instant-on chemical heat source to drive a sodium-amide reactor. Sodium is certainly a lot cheaper than ruthenium.
48V systems typically don't have batteries big enough to be worth using as plug-ins (not even the regular Prius does). The cost of a line-power charging system would be mostly wasted. However, electrifying the various accessories like power steering and A/C reduces a lot of parasitic engine drag and boosts efficiency there. One of the major issues of 48V is standby power drain for the various electronic modules which require "keep-alive" power. The practice in the day was to use linear regulators between battery voltage and whatever the chips want to be fed (5V then, today 3.3V or even less). Obviously this doesn't look so good when you're feeding 48V and dropping 45 volts as resistance heat. I'm not sure where things are now, but I suspect there will be a standby power bus running at 5V or less and fed from battery by a dedicated switching regulator running at much higher efficiency.
This sounds very good. Vehicles of this scale tend to get very poor mileage in city traffic, while it's the place where electric propulsion shines. If there's an effort to provide charging wherever they park regularly, most of the liquid fuel consumption simply goes away.
Found the basement-dwelling Trekkie.
Tesla Model S's passed 1 billion miles cumulative... 2 years ago. http://insideevs.com/tesla-model-s-passes-1-billion-miles-driven/
Electrolytic hydrogen is multiples of the price of SMR. The idea of power-to-hydrogen from renewables is the current opium dream; the real purpose of the hydrogen car is to give the natural gas industry a lock on vehicle fuel for as long as it lasts.
Lets say you park at 9am and need the car back by 5pm, and have 7 KwH capacity that needs to be replenished. And if it's a cloudy day with low or no wind, you have little or no renewable power that entire day. It doesn't matter if the wind is forecast to come up around 7 PM, because you needed it on-line no later than 3 (assuming 240 VAC 16 A charging). PHEVs can do regulation and spinning reserve. They can't really do much in the way of time-shifting.
I think you're right, gryf. Battery-electric eliminates all the headaches and chicken/egg problems of hydrogen, and fast-charging technology like Busbaar and its successors are already here.
No, they're absorbing and desorbing H2 from the hydride material which is accompanied by heat release and uptake. Clever move, and all solid-state too.