I cant believe they dont use the propellers to charge the batteries in mid-flight !!!
/s
Also, (on a more serious note) - what is the “newish” system called with lots of small propellers in front of the leading edge of the wing - to push accelerated air over it thus improving lift? … I thought those combined could be a more viable way
yeah, I want a proper 100 octane aviation fuel fire at those altitudes … one needs to go out in style …
(never get this argument for e-cars, either … mostly coming from guys on a Dodge RAM, sitting on top of 120 liters of gasoline)
Those are called “blown wing”. NASA has a blown wing EV test aircraft, the X-57 Maxwell. Some day, they may even take it out for a flight or two. Also, googling just now, I found this article about it.
Gasoline in a fuel tank almost never spontaneously ignites. It is extremely rare in car batteries, but I believe there are documented cases. Worrying about it for real (as opposed to using it as an excuse to oppose EVs) is just another example of humans being really bad at risk evaluation.
I do plan for my next vehicle to be an EV. It was going to be a Tesla, but Elon is such a jerk I’m not sure I can go that route.
The real problem with Tesla right now is that the next project they’re working on is an android robot. Ideally, they should be working on a less expensive car similar to the Model 3, but from reports, that project has been back-burnered. No doubt this is Musk’s doing; robot is sexier than cheap car.
DOE ARPA did an evaluation of future use of renewable fuels (using direct fuel cells) in aviation. Studies on a ATR 72 (70 passengers) showed the following results for range :
Biodiesel -->2500 Miles
Methanol -->1800 Miles
Dimethyl ether (DME) -->2100 Miles
Ethanol -->2400 Miles
Ammonia -->1650 Miles
Liquid hydrogen -->1050 Miles
Compressed H2 (700 Bar) -->650 Miles
Page 5 of presentation : https://arpa-e.energy.gov/sites/default/files/Grigorii-Soloveichik-Fast-Pitch-2018.pdf
The winning configuration for aviation, in the opinion of many researchers is the combination of fuel cells + batteries. This is with using existing technologies and assuming no major breakthroughs in fuel cells.
It is to be noted that the Marine transportation industry is betting on Methanol and Ammonia, while consumer car market is betting on compressed hydrogen e.g. Toyota Mirai.
Also pointing out that Methanol and DME are mature fuels that can be manufactured from Biomass and many projects are in conceptual design phases.
Also pointing out that there are a lot of biomass plants that people are generally not aware of. The US South is exporting volumes of biomass pellets to Europe, as we speak.
https://environmentalpaper.org/tools-and-resources/mapping-bioenergy/
The consumer car market is going with battery electric. It’s mainly Toyota and maybe some other Japanese makers who are going with H2. Everyone else is skipping hydrogen.
An hour isn’t very long. Suppose there is very bad weather with wind shear, etc. Normally, planes will either be routed to another airport or will circle above until conditions improve. It might be good as a D.C. to New York shuttle because that is only a little over 200 miles via air. Plenty of wiggle room.
I was talking about the fuels referenced in the list.
And Hydrogen is doing well. Amazon invested 2 Billion USD recently Amazon invests in green hydrogen companies
Many warehouses have already converted to hydrogen and many are in the process.
The US DOE has offered $7 Billion recently DOE offers up to $7B for highly anticipated hydrogen hub program | S&P Global Market Intelligence
Hydrogen is alive and well. Hydrogen cars are electric cars too - just instead of the battery, you have a fuel cell.
“Blown wing” is a fine term for what it does for the wing. The multiple small propeller arrangement itself is commonly called “distributed propulsion”.
There is lots of evidence that will be the future of propeller-driven designs as we switch to something more like locomotive practice with a single (or dual) large source of electricity such as batteries, fuel cells, or turbines pr diesels turning big generators. The few large sources will then be electrically connected to multiple small motors to turn multiple small propellors, rotors, fans, etc.
Well I guess if you’re flying in a DC-3. Otherwise, Airliners use jet fuel.
Lithium batteries are prone to cascade failure. This is a serious concern in the certification process. each battery pack contains hundreds/thousands of individual batteries of which any one of them could fail starting a chain reaction.
A few years ago Tesla stood out as a leader of EV’s. But ALL the major automakers have stepped up and are making their own. This greatly dilutes the place Tesla cars held. I suspect that Musk knows Tesla will be in a long term declining market share by default. He still doesn’t have his truck for sale at a time when Ford and GM are already on the market.
A declining market share is fine as long as the total market is increasing–which it is. They are still growing exponentially:
Ford needs to ship their EVs in high volume before they can be considered a threat. They are only producing a few thousand F-150 Lightnings per month. It would have been surprising a decade ago, but it turned out that Tesla is the one that can produce EVs in high volume and the other automakers that would have to play catch-up.
Even Musk says the robot is 5 years off. Right now it’s just a recruiting tool.
No, the reason why Tesla has pushed back their upcoming car releases (Cybertruck, Semi, Roadster, and “Model 2”) is simple: they’re battery limited (or have been until very recently–I think they’ve indicated that this may be less of a problem shortly). The Model 3 and Model Y make them more money per battery cell than those upcoming models would, and they are selling all they can make (with a waiting list).
When that stops being true–either because demand slacks off or production catches up–we’ll see a bigger push for the next-gen products. But at the moment, Tesla has some of the biggest margins in the industry and no reason to disrupt that.
As far as how all of this relates to the OP, battery costs and supply are going to affect everything. Cars, grid storage, airplanes, etc. I think we’ll pretty quickly see EV airplanes that can perform short-haul flights, say 500 miles (I agree that long-haul electric planes are a very long time off). For those flights, the only remaining concern is cost. Electric planes will have extremely low running costs (no fuel, simpler maintenance for motors, etc.) but probably high capital costs. It’s not clear yet how those tradeoffs will play out in the long run.
I’m about to board a plane and don’t have time to find links, but the two programs in this area that I’m aware they ended up funding are REEACH and ASCEND. Those search terms should pull more info if people are interested.
IIRC one focused on fuel cells and the other on power electronics
I forget where I read it but IIRC they mean Alice to be for short hops. They are hoping for LA or San Diego to Las Vegas. New York to Boston and stuff like that (maybe Chicago to Detroit or Dallas to Houston, Miami to Tampa or Orlando).
There are lots of short hop routes this plane could (probably) do.
At the moment Tesla is playing catch-up to Ford and GM in trucks. Time is not on Musk’s side.
Tesla may very well end up being the world’s battery king and not car maker. Too soon to tell. But the point is a startup may do great until the established competition weighs in with more resources and experience.
The same was said about the Chevy Bolt, which beat the Model 3 to market. Last quarter, Tesla sold 325k Model 3+Ys and GM sold 15k Bolts (which was an increase from the zero they sold earlier in the year due to a recall).
Back to the subject of airplanes: electrics have the distinct advantage that they don’t require oxygen for combustion. They could gain a great deal of efficiency by flying at what we’d consider extreme altitudes, like 80k feet. It would require very different plane designs, however, so I’d expect commercial versions to be quite a ways off.
You can also use different materials. Using aluminum instead of copper is an obvious one. However, sodium is an even better conductor per unit weight. And since it’s liquid when warm, it can be circulated through a radiator so as not to overheat.
I think that is terribly intertwined … and that is a huge competitive advantage tesla holds … as a significant part of a EV price/cost (50%?) goes into the battery … If you manage to produce your batteries 10% cheaper then your competitors, you have a 5% margin advantage (which might be 50% of the total of a margin that is being made off of the car)
but isn’t this an issue beyond the energy source (EV vs. ICE)? … I am thinking in such thin air as 80k ft, lift is lower, thrust from jets as well and also push (or pull) from propellers … of course, drag is also lower … (or am I off base?)
IOW if we disregard “low O makes for lousy combustion”, what would be the most efficient flying altitude for non-combustion propulsion ? (if there is one)
Yes, all of those tradeoffs change–but since drag is lower, you can fly faster, which increases lift. Thrust may be lower at the same motor speed, but because it’s power-limited, the prop could be spun much faster (electric motors have a much wider power band than turbines).
It would require a fairly radical redesign, and some development in areas that are not well explored at the moment. Still, it’s probably required for long-range electric craft (as well as continued battery development).
Electric motors may also be able to make certain unconventional designs practical. Wings are always some tradeoff between cruise efficiency and being able to take off/land at reasonable speeds. Since motors are so light, they may be able to boost performance at crucial times (like the blown wing concept mentioned above).
Unless there’s some radical prop design in the works the efficiency is going to be linked to subsonic tip speeds.
The most likely use would be a solar powered plane that loiters at slower speeds.