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Davemart, yes of course: governments never fail, all engineers always agree, and none of them have vested interest at all. Therefore, I guess you support all previous renewables state supported energy policies as: - USA E85 corn ecological and economical disaster - Brazil's sugarcane ecological and humanitarian disaster - Sweden imported palm oil, an Indonesian ecological and humanitarian disaster - Spain's solar bubble around 2008, the state subsidizing a crazy amount of solar at uneconomical prices and causing a nasty price problem for a decade ...and many many more braindead schemes...just because some engineers did put a stamp on a government sponsored report. And I have checked your marvelous report. It's a riot: - They never ever mention combined heat and power for hydrogen. Just mixing some testimonial percentage of hydrogen in the gas pipes. In fact, they suggest eliminating existing fossil fuels based combined heat and power systems. Great idea, lol. One the few efficient energy systems in the UK, let it go first. - They suggest to obtaining the hydrogen from electricity OR natural gas OR biomass. Yeah, what a great concept. Reform methane into hydrogen and then inject it in methane pipes in small proportion. That will store a ton of energy, fantastic idea. Or get it from biomass, yeah, why not. Devise a complex system to get hydrogen from biomass and store it. It does not matter that biomass CAN BE perfectly stored without conversion, as is more efficiently used in a biomass burning plant. Biomass is ALREADY energy storage than can complement renewables. Yeas, I am real impressed. The documents have nice pictures and graphs, that I will admit.
Davemart, "Heat", and "combined heat and power" are two different terms and two different uses fuel. I was replying about "heat", which was proposed by Roger. BTW, combined heat and power does not make sense in all countries either. We don't have much use for that much hot water in the mediterranean countries for example. And you still have to factor the crazy cost of the fuel cells and electrolizers. Show me the numbers. Next, "Japan did X things" is not argument at all. The USA & Brazil still supports that criminal ethanol for cars nonsense, so what? The fact that a whole country pursues a tech does not make it legit. Right now Japan has a project about getting hydrogen from lignite in Australia and importing it by ship; I am pretty sure it does not make sense to you or anybody here in greencarcongress, does it? Injecting hydrogen in gas pipes is just greenwashing. That electricity is much better spent using it directly, no matter if we are talking about cooking or heating. Hydrogen as storage is just the most expensive and inefficient way of storing renewable electricity there is. Even CAES would be cheaper. The only rational use I can see for hydrogen is using it as feedstock for synthetic fuels and other product. I will check this UK plan, but I have seen plenty of them through the years and they are usually plenty of wishful thinking and happy happy economic assumptions.
Oops, I meant "any rational being choosing Option B".
Roger, hydrogen for heating is the most preposterous use one can imagine. Option A: use a heat pump, with a positive COP which can give you up to 2 units of heat for each unit of electricity Option B: bring an hydrogen pipe (with all its problems) to your home, burn 1 unit of heat which took nearly 2 units of electricity to synthesize. I cannot imagine any rational being choosing Option A. Even where a heat pump can't work, simple resistive electric heat is much better than hydrogen! Better efficiency without the expensive installation.
No info on wh/kg or metals used? The specs are not that impressive, and without that information they are just uninteresting.
I can accept the high torque vs. weight argument, however the article is illustrated with a car drivetrain. I don't think it makes any sense for cars, there you want the best power to weight ratio (and hugh efficiency too). This motor just does not seem to shine in that area. Hub motors for cars is another seemingly no-go idea. You want to remove weight from wheels, not adding more.
I checked the specs on their web and they are a bit underwhelming. Their power to weight ratio is not that different from many pm motors, but the design seems much more convoluted and difficult to build.
I will concede that there are fewer battery fires in other car brands, but I don't see that as significant. Yes, there is only 4 or 5 Hyundai Kona fires, 1 Taycan fire, 1 Panamera fire, 1 eGolf fire, 1 or 2 Fisker Karma fires,and the list goes on in that fashion... However, how is that significant? All these cars have sold a fraction of what Tesla sells. 8 Tesla fires versus all the cars sold in this list hardly seems worse. In the world of cheap electric motorcycles, fires are pretty common, and nearly all of the are pouch or prismatic. I can accept Nissan having a better track record in security (which imo is largely offset by the horrible tales of battery degradation; Nissan is hardly a good example of good EV engineering), but I am pretty sure this not due to cell format, but better electronics. In my experience (and yes, unfortunately I have first hand experience) a parked EV burns when overcharged. Any cell going north of 4.3V starts heating. Now, when you overcharge a pouch or a prismatic, it heats, swells, punctures and starts emitting gas at fast speed. If the cell is enclosed, the gas ignites very easily. I have seen this several times performing tests. A very similar process happens with prismatics, although they swell less dramatically and usually puffs less. Guess what? The only format which offers a [b]passive protection[/b] against overcharging is the cylindrical format. An overcharged cylindrical cell contains pressure to a limit, and then breaks electric contact using a pressure valve. This is called a CID. All of the cylindrical cells I have tested for overcharging did correctly break the circuit. The only way I have caused cylindrical cells to fire is puncturing them using a nail, and even then, only those rated for high discharge would catch fire.
Davemart, "Tesla leader in battery fires"? Lol, now it's obvious you are just trolling. There has been much more fires in pouch and prismatics than in cylindrical batteries. The number of fires in prismatics is less known, as the technology is mostly used in china, but still many reports exist on cars and buses burning. Prismatics are usually pretty thick, around 50 mmm. For thinner cells they usually choose pouch formats, and there are very few examples of them being cooled. The Chevy Bolt is one of them, and the (few) existing battery degradation graphs show faster aging than Tesla packs. I see your idea of Tesla engineering is that they don't know anything about batteries; I find this pretty fun.
Davemart, the secret sauce which provided excellent lifespan to Tesla batteries is perfectly known at this point: keeping the cells cool. Not just ambient temperature, but cool, south of 30 degrees Celsius which ages any Lithium cell fast. And this needs small cells to avoid heat pockets. Lithium-ion materials are not good heat conductors. This was told to me by a Tesla engineer himself, years ago, and I think is common knowledge by now. The other factor they were trying to avoid was electrode paste movement inside the cell. For example, in vertical pouch cells the paste tends to fall slowly to the bottom on each cycle. Cylindrical cells behave much better in that respect. So yes, of course they know bigger cells are cheaper to assemble, but robustness was the priority at it's obvious to me their bet payed off. Other early electric cars like the Leaf killed their battery in less than 8 years, I am bored of hearing bad reports about them. I wish they would have used the cylindrical format. The 2170 was Tesla's compromise between "can be cooled efectively" and "as big as possible". The reason of the bigger new format (4680) was explained yesterday: the tabless cell format they have created has less electric resistance, a lot less, therefore it produces less heat on charge or discharge. That allows a bigger cell to be kept cool as previous packs.
Davemart, I don't think the new 4680 format shown in the conference is "prismatic". They look pretty cylindrical to me. Tesla cylindrical, cooled cells have the best lifespan track record on the industry. All your talk around it is nonsense. BYD prismatics are comparable, but much heavier. The energy density of the new cell has not been clearly explained in the conference; maybe there is a tradeoff removing Cobalt. Maybe the energy density is really better, but at pack level that improvemente is reduced (due to the heavy cooling systems Tesla uses).
Back in 1996, a record of 604 km was established hypermiling a Solectria Sunrise. Using just a 25 kwh battery. That was a design which I would by in a blink, unfortunately it was to soon for EVs.
This little car is cool, but there is no info about the battery.
Severa interesting things here... The feature I like most is the motor, I hate the unnecesary use of neodimyum on electric cars. Unfortunately, only Reanult build EVs without it.
Nikola? A leader? What are these guy leading, vapourware? :D
That's a really nice chemistry. 400 wh/kg at cell level, all materials are abundant as far as I have read (it does not need litihum, cobalt or nickel). Lifespan is probably decent, like all Titanium based batteries. It's a pity all money goes to developing lithium batts.
You can reduce the pulsating torque of a SRM using several techs. like: - Different number of stator winding poles and rotor teeth. You need a high number of winding poles for this, so I guess that's what they are aiming for. - Skewing. - Wave shape modulation. My pet tech. is the flux switching motor, which is closely related to the SR motor. Its has the same troubles (vibration due to irregular torque) and the same fixes.
I don't think FC are cost effective in any of those cases. Ship engines are cost sensible, fuel intensive, and lifetime intensive. Existing FC can't compete in those specifications. Train engines are less cost sensible, but the rest applies. Current LiFePo4 and LTO are cost effective and have long lifespans, plus you save a lot in fuel using batteries. I believe ships should bet in LNG as a way of reducing pollution and enhancing energy independence as sustainability (biogas can easily be produced if needed by any country, at quantities large enough to support shipping operations).
I don't get why the train industry is waiting so much to use modern batteries instead of expensive overhead lines... Batteries slightly bigger than this one are perfect for railroads. LiFePo4 or LTO chemistries will give you >10 year of constant operation and unlimited power. Exchanging batteries in the route end points should be trivial for the rail industry. And the "fuel" cost would be so low, charging the batteries at valley hours... That would make much more sense than electrifying ships, which is probably one of the most difficult applications for batteries.
What a pity, it seems BYD is going ternary lithium. I was hoping they would keep using LiFePo4 and I could buy one of their cars in my country in the future...No nickel, no Cobalt, that's what I understand as sustainable. Also, LiFePo4 is finally getting cheap and competitive in China. You can already ~$120/kwh in many products.
These guys are promising $150/kwh now, and $85 in 2020. I wish them well, but that's not cheaper than current li-ion ($100/kwh). Who knows what the cost of li-ion will be in 2020! This is highly reminiscent of many solar technologies which have died recently, because traditional silicon cells kept going down in cost fast.
Heterojunction cells are about 22% efficient, just a bit more than monocrystalline cells (which are dead cheap by now). And the voltage problem the claim have solved, is just silly. In nealy all uses, cells (electrochemical, solar or otherwise) are operated in series, and balanced if needed. There is no real advantage on coupling directly the solar cell with the electrolyzer to gain a few marginal points in efficiency. If you go "parallel" like these guys are doing, you end up needing huge copper bars for conductors. Plus, any change in solar radiation lowers the voltage & the model stops working. Much better to use a DC-DC device, which are 95% efficient today. The only new (to me) information I get from this article is that PEM electrolyzers are very efficient, about 65%. Cool, but it seems these devices have their own problems which remain to be solved (mostly related to lifetime). Seems like poor research to me.
Does "Cryogenic fluid" means they are using liquid air or nitrogen? If that's the case, how do you compute the efficiency? Producing liquid nitrogen is an energy-intensive proccess. I think this 60% efficiency does not account for energy spent in producing the cryogenic fluid.
These trucks have no traction battery. They don't charge from the wire. When the electric contact is lost, the diesel engine kicks in instantly Trolleybuses used to have big problems when electric contact was lost, but that's not the case for these trucks.
Sublime, I think you misread the article. It says: "specific energy of 152 Wh/kg". Barely better than LiFePo4, but half the energy density of modern Li-ion. Also, we don't know the chemistry, wyth all the components. Maybe nickel or manganese is used too...Lithium cells are usually complex beasts. BTW, manganese is really cheap an abundant. Nickel and cobalt are problematic, though.