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The Electric Airplane Is Coming

Unknown Lamer posted about 3 years ago | from the but-what-about-flying-electric-cars dept.

Science 187

An anonymous reader writes "The electric car is so yesterday; electric airplanes are coming. A battery electric-powered ultralight aircraft has been flying for the last year. A series-hybrid motor glider and a concept for an all-electric, 50-seat passenger plane were introduced at the Paris Air Show."

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First post from an electric airplane! (4, Funny)

GameboyRMH (1153867) | about 3 years ago | (#36887638)

Writing from my Alienware laptop while running Crysis, powered by the cig. port! This is so much fu^H^H NO CARRIER

Re:First post from an electric airplane! (1)

Bob the Super Hamste (1152367) | about 3 years ago | (#36887668)

This is probably the best first post I have seen in a while

Re:First post from an electric airplane! (0)

GameboyRMH (1153867) | about 3 years ago | (#36887710)

I figure anything I can do to take the opportunity away from the trolls is a positive contribution :)

Re:First post from an electric airplane! (0)

Anonymous Coward | about 3 years ago | (#36887754)

This is probably the worst second post I have seen in a while.

When? (1)

impaledsunset (1337701) | about 3 years ago | (#36887706)

From TFA: 'The power capacity of battery technology, he continued, would have to grow by “at least a factor of four before we are near where we need to be to accomplish this.'

This is when electric aeroplanes would become really feasible.

SMES (1)

Tatarize (682683) | about 3 years ago | (#36888592)

You could use superconductive storage today and get the right battery-weight. It would actually weigh much less than jet fuel to add enough power to a series of superconductive coils and store the power. A typical coil of SMES in current use can get about a 1 MW/h which is 3600 Megajoules, typically a kilo of jetfuel has something like 44 megajoules of power, so one coil would replace 81 kilos of jet fuel. You'd need like 57 thousand kilos of jetfuel to go a typical 3,500 statute mile flight. Which is 705 superconductive coils, which would weigh less than the jetfuel currently does and would cost less after being built on a per flight basis and could be refueled as quickly as one could give it new electric power.

It might however have clear health effects with that much localized magnetic fields and break a lot of electronic devices, and refrigeration is a giant pain in the ass without having it 30k feet in the air.

Re:SMES (2)

bwayne314 (1854406) | about 3 years ago | (#36888694)

You also didn't take into account that the jet-fuel payload decreases throughout the duration of the flight as it is burned up, typically by the end of the flight most of the fuel is gone and the plane is much lighter, resulting is better fuel efficiency. While batteries can't be dumped out of the plane after they are discharged.

Re:SMES (1)

Jeremi (14640) | about 3 years ago | (#36889158)

While batteries can't be dumped out of the plane after they are discharged.

Sure they can. ;^)

Re:SMES (0)

wagnerrp (1305589) | about 3 years ago | (#36888996)

When you start using units like 'megawatts per hour' to describe energy, nothing else you say engineering related has any credibility.

Re:First post from an electric airplane! (0)

Anonymous Coward | about 3 years ago | (#36887864)

This is so much fu^H^H NO CARRIER

lol.... ATH0

wow that brings back memories

Re:First post from an electric airplane! (1)

antdude (79039) | about 3 years ago | (#36889136)

Why were you using dial-up Internet? ;)

So does this mean I can stop seeing those ads (1)

Bob the Super Hamste (1152367) | about 3 years ago | (#36887652)

So does this mean I can stop seeing those ads and comments stating that we don't have anything to run our planes on other than oil based products.

Re:So does this mean I can stop seeing those ads (1)

GameboyRMH (1153867) | about 3 years ago | (#36887674)

Maybe some day, but right now this is only practical for light and ultralight aircraft. Still no replacement in sight for large aircraft.

Re:So does this mean I can stop seeing those ads (1)

Mindcontrolled (1388007) | about 3 years ago | (#36887746)

Well, we have at least seen test flights by major airlines on biodiesel - then again, a turbine driven engine will probably eat most flammable crap thrown at it. Obviously bio fuels are not really a replacement at the current state, though algae derived stuff might be able to be mass produced in somewhat sufficient quantities at some point. The most sensible "replacement" would probably be not having bloody strawberries flown in over half the world in freaking winter...Personally, I'd not count that as a loss - waiting for seasonal products to come up again doubles the enjoyment anyway.

Re:So does this mean I can stop seeing those ads (1)

vlm (69642) | about 3 years ago | (#36887922)

a turbine driven engine will probably eat most flammable crap thrown at it

Soot and ash production make them extremely unhappy. Even the finest powdered anthracite coal just isn't clean enough. Other than that, yes correct.

Re:So does this mean I can stop seeing those ads (1)

Mindcontrolled (1388007) | about 3 years ago | (#36887986)

Ah, yeah - that was a bit too general. I didn't even think about powdered coals - what I really meant was "any flammable distillate, however crappy". I guess the problem with coal would be the inevitable content of silicates that glass up and become hellish abrasives, rather than the soot, though?

Re:So does this mean I can stop seeing those ads (1)

michelcolman (1208008) | about 3 years ago | (#36888006)

Well, it's correct for old jet engines, but the newer models are so fine-tuned to their specific fuel that they need a fair bit of tweaking before then can run anything else without having a significantly reduced power output and life span.

Re:So does this mean I can stop seeing those ads (1)

afidel (530433) | about 3 years ago | (#36888016)

I'd rather not eat gruel for half the year TYVM. Now as to electric planes, I'm not sold. Even if the electric system is twice or even four times as efficient per unit of energy you still have to deal with the fact that kerosene/JP1 is about 40x more dense per unit weight and 80 times per unit volume than Lithium Ion batteries.

Re:So does this mean I can stop seeing those ads (1)

Mindcontrolled (1388007) | about 3 years ago | (#36888046)

Importing strawberries all year long and eating gruel for half the year is a wee bit of a false dichotomy, isn't it? True on the lack of energy density difference between kerosene and current batteries, though.

Re:So does this mean I can stop seeing those ads (1)

afidel (530433) | about 3 years ago | (#36888178)

Not really, fresh local foodstuffs are only available from about mid June to late October around here. If it weren't for imported foods we'd have to go back to using canned, jarred, and otherwise preserved foods for half the year. Now it might be a bit of a stretch because a lot of things can be moved by ship and rail, but that too has consequences as it leads growers to try to minimize losses in shipping which leads to monoculture and a less healthy and tasty products that are more durable.

Re:So does this mean I can stop seeing those ads (1)

Mindcontrolled (1388007) | about 3 years ago | (#36888206)

True, but there is a continuum - and a lot of fresh produce can be shipped without airfreight, and thereby a lot more energy efficiently. I am not saying that we should go without any fresh imported stuff in winter, but some of it is frankly ridiculous as we are doing it now - and, beside any moral consideration - not affordable given the oil supply situation that will hit us in the next 2 decades. That's not a "you are doing it wrong" argument - that's a "barring radical new developments, we will simply not be able to afford it" argument.

Re:So does this mean I can stop seeing those ads (1)

element-o.p. (939033) | about 3 years ago | (#36889068)

...a lot of fresh produce can be shipped without airfreight, and thereby a lot more energy efficiently...

As was said earlier in this post, that depends entirely upon where you live. I live in Anchorage, Alaska. You can get here by other than by air, but not reliably. Anchorage is (barely, I'll admit) north of the dividing line between ice-free and iced-in seaports. There are two reasonably major highways through Canada, but they both are subject to icy roads in the winter, and as they are in the mountains, that can cause problems as well. There are a lot of railways in south-central Alaska, but I don't know about railways to Anchorage from the lower-48. If you live outside of Anchorage, all bets are off -- Iliamna, for example, is only about 200 miles from here, but the *ONLY* way to get there is by air. Likewise for most of the rest of bush Alaska.

Re:So does this mean I can stop seeing those ads (1)

ryanov (193048) | about 3 years ago | (#36888426)

What is wrong with using canned or jarred vegetables?

Re:So does this mean I can stop seeing those ads (1)

afidel (530433) | about 3 years ago | (#36888438)

The flavor and texture suck compared to fresh and they normally use salt as a preservative which I need to avoid over-consumption of.

Re:So does this mean I can stop seeing those ads (1)

element-o.p. (939033) | about 3 years ago | (#36889080)

You cook the nutrients out of them and add a boatload of preservatives, some of which cause allergic or other reactions in some people, for starters.

Re:So does this mean I can stop seeing those ads (1)

Bob the Super Hamste (1152367) | about 3 years ago | (#36887810)

Well it is a start. Those ads always bothered me especially since there are planes that run on things other than fossil fuels, alcohol probably being the next most common. That and the fact the ads were always by oil companies.

Re:So does this mean I can stop seeing those ads (1)

michelcolman (1208008) | about 3 years ago | (#36887970)

But... they showed this beautiful model! You know, made on a computer! Shiny and everything! So this thing must be basically finished, right?

Re:So does this mean I can stop seeing those ads (1)

fuzzyfuzzyfungus (1223518) | about 3 years ago | (#36887786)

Probably not, given that synthesizing hydrocarbon fuels from virtually anything with available hydrogen and carbon is doable if you merely want energy storage rather than cheap energy. The uphill battle for things like batteries is not merely that they aren't where we want them to be for storage; but the fact that their oil-based competitors provide both storage and cheap energy at the same time.

Unlike scarce elements, like helium, that have unique physical properties, oil isn't especially special chemically except for the fact that centuries or millenia of ancient sunlight conveniently shoved it up the chemical-potential-energy slope for us. If you have energy available by some other means, shoving hydrogen and carbon up the slope yourself in order to store energy in a convenient chemical form is perfectly doable.

Re:So does this mean I can stop seeing those ads (1)

lyml (1200795) | about 3 years ago | (#36888318)

Synthesizing hydrocarbon fuels, though possible, is not only expensive. It is really expensive.

If you exclude other fossil fuels as a suitable candidate (while they can be synthesized into liquid hydrocarbons at an efficiency of about 0.5 they are also running out). The chain electricity->synthetic jet fuel->combustion engine is about one tenth as effective as electricity->battery->electric engine.

So while battery tech might not be quite there yet, even if wide scale synthesis of jet fuel was already existing, there would still be a drive force towards electric airplanes.

Re:So does this mean I can stop seeing those ads (2)

Grishnakh (216268) | about 3 years ago | (#36888634)

The chain electricity->synthetic jet fuel->combustion engine is about one tenth as effective as electricity->battery->electric engine.

So while battery tech might not be quite there yet, even if wide scale synthesis of jet fuel was already existing, there would still be a drive force towards electric airplanes.

The entire problem is battery tech, and it's not looking like this is going to change any time soon. The efficiency problem really isn't that important, because our crappy battery tech simply makes it completely infeasible to have real electric airplanes: they weigh too much for the amount of energy they store, whereas liquid fuels (whether kerosene/JP1, diesel (yes, there's airplanes that can run on diesel), or a vegetable-derived version of one of these) have a much, much higher energy density, making them useful for aviation. Because an aircraft has to use its power to lift itself up in the air, against the force of gravity, along with its powerplant and its fuel supply, things are a little different than with ground-based vehicles. Powerplants with a high power-to-weight ratio are very important, as is fuel with a high energy density. It's even worse in helicopters.

Right now, there's already a big desire to start moving to electric cars and away from fossil fuels there. However, again, battery tech is the limiting factor. Everything else is a solved problem; high-performance electric motors are no problem, and there's electric accessories available (A/C compressors, power steering, etc.). But we're still a ways from having good battery tech for cars that'll make fossil fuel engines obsolete, and our best electric cars don't even have a 100-mile range it seems, plus the recharge time is a big problem. And electric cars don't come close to matching the comfort or performance of midsize, average regular cars. The battery tech needed for electric aircraft will be another order of magnitude or two better than what electric cars need, so we're really a long way from this goal.

Battery technology that's an order of magnitude or two better than what we have now would literally change the world, as all the other pieces are in place to have electric vehicles. It's the only thing holding us back. But there's no way to know how far away this revolution is. Someone might invent something much better in 10 years, or it might take 200.

Re:So does this mean I can stop seeing those ads (0)

Anonymous Coward | about 3 years ago | (#36887930)

No, of course, airplanes fly by wishes and hard drives. When will I stop seeing posts from clueless dreamers who don't understand basic physical reality and engineering limits? Idiots who conflate our information processing capacity with real-world results. Gigahertz don't propel mass. Gigabytes don't fly at the speed of sound.

Re:So does this mean I can stop seeing those ads (1)

aevan (903814) | about 3 years ago | (#36887938)

Shouldn't ever have had to see them. The Russians made a hydrogen-fueled commercial airliner (Tu-155) 23 years ago. They later changed fuels to nat gas, but she initially was oil free (fuel-wise).

Re:So does this mean I can stop seeing those ads (1)

zAPPzAPP (1207370) | about 3 years ago | (#36888840)

Yes, they now run on atoms and stuff.

Re:So does this mean I can stop seeing those ads (1)

prefec2 (875483) | about 3 years ago | (#36889094)

We could always use hydrogen to fuel planes. The question is: Is it wise to use planes for short distance travel when we could use more energy efficient personal transportation devices? The electricity has to come from somewhere and we have to go a long distance to rebuild our energy system with renewable energy. Well maybe in the US where we have not a large high speed train net, planes are the only fast mass transportation facility, but in Europe we definitely could use trains as a replacement.

Finally (1)

tripleevenfall (1990004) | about 3 years ago | (#36887670)

The personal flying car is here.

Amazingly fantastic batteries! (2)

localman57 (1340533) | about 3 years ago | (#36887672)

A battery electric-powered ultralight aircraft has been flying for the last year.

Flying FOR A YEAR? Crap. My Volt only goes 35 miles then I have to charge it or burn gas. I want one of those airplane batteries!

Re:Amazingly fantastic batteries! (1)

vlm (69642) | about 3 years ago | (#36887964)

A battery electric-powered ultralight aircraft has been flying for the last year.

Flying FOR A YEAR? Crap. My Volt only goes 35 miles then I have to charge it or burn gas. I want one of those airplane batteries!

The solar impulse guys are planning on about one month. My experience with lithium batteries seems to be either they die at about 50 charge cycles or they run for about 500 cycles, with few failures in between... if they get a good set of batts then 2 or 3 years would be possible.

http://en.wikipedia.org/wiki/Solar_Impulse [wikipedia.org]

LOL (-1)

Anonymous Coward | about 3 years ago | (#36887692)

The render of a concept of a dream of a hope of an electric airplane is coming. There will be no such thing. We are running out of cheap energy. There is no way an electric airplane can compete with kerosene powered turbines. For one, where will the energy come from? For another, how will it be stored? The periodic table of elements is pretty much complete. We know the materials, we know the limits. Ain't gonna happen.

But keep fucking that chicken, maybe one day we'll have electric bungalows on Mars!

Bahahahaha!!!!

Re:LOL (3, Informative)

Grishnakh (216268) | about 3 years ago | (#36888716)

Don't be dumb; there's an infinite number of molecules out there that can be made from the elements on the periodic table. For instance, carbon nanotubes have only been discovered relatively recently, and have all kinds of interesting and useful properties, yet carbon the element has been known since ancient times, and is probably one of the first elements named and understood by scientists when they first invented chemistry. More recently, it's been discovered that you can make nanotubes with boron and boron nitride, which have very different properties from the carbon variety (BN tubes are insulators, whereas carbon tubes are conductors).

http://www.newscientist.com/article/dn13143-boron-nanotubes-could-outperform-carbon.html [newscientist.com]

This is just the tip of the iceberg. There's an untold number of "metamaterials" out there waiting to be discovered, things which don't occur in nature in any significant quantity, have all kinds of amazing properties, and are made from simple elements that we've known about for ages (boron and nitrogen aren't exactly new discoveries).

Re:LOL (0)

Anonymous Coward | about 3 years ago | (#36888968)

But they're constrained! Most of those molecules have no interesting or useful properties. They're either viciously reactive, like chlorine trifluoride, or fragile, or dissolve in air, or have no strength, no tensile strength, or they fracture. Or maybe they have great strength, but weigh too much, or use elements we don't have in huge amounts.

Carbon nanotubes? Give me a break. Unless the bulk properties can be demonstrated, it's just a lab curiosity right now. And it's still carbon! It'll burn at 900C just like coal, and diamonds. So?

"things which don't occur in nature in any significant quantity"

You don't see that as a problem? So now, you have to manufacture all these materials, with our dwindling energy base. Good luck.

Look, it's simple. This is all delusional. Metamateriasls and wishes don't lift a feather.

It's great that you have this faith and your religion makes you all positive and stuff because you have a fast computer now, but really, you sound like a child.

Storage capacitor manhattan project (4, Interesting)

xtal (49134) | about 3 years ago | (#36887698)

We need this more than any other technology right now, and it's a solvable problem.

Want something to stimulate the economy? That'd do it.

Re:Storage capacitor manhattan project (1)

RocketChild (1397411) | about 3 years ago | (#36887788)

Yeah, but GE would just offshore the batteries to be built in China and keep the tax savings for themselves.

Would they? (0)

Anonymous Coward | about 3 years ago | (#36888182)

Most of my 'green' crap - my ridiculously expensive LED bulbs, for example - is made in the US.

Not that China isn't kicking our ass at green crap, but lolecodweebery has improved our economy. The question now is whether or not Americans have learned their lesson with regard to rock bottom prices and what actually occurs to bring said prices to stores.

Re:Would they? (1)

nschubach (922175) | about 3 years ago | (#36888252)

Not sure, but I bought some of them US made LEDs when I moved into my new house. I didn't, however, buy all LED because they are incredibly white light (vs the halogen replacements I got for the normal bulbs.)

Re:Storage capacitor manhattan project (2)

Jeng (926980) | about 3 years ago | (#36887896)

We need this more than any other technology right now, and it's a solvable problem

Is it in the same category of solvable problems that Fusion is in?

Re:Storage capacitor manhattan project (1)

localman57 (1340533) | about 3 years ago | (#36887936)

Yeah. What do you think we're gonna use to fill all those capacitors?

Re:Storage capacitor manhattan project (0)

Anonymous Coward | about 3 years ago | (#36888646)

Fusion is solvable, if we were to get behind it 100% and throw money at building, testing, and theorizing solutions to it.

They are building ITER & DEMO...What will be the one little thing that makes the difference?

Re:Storage capacitor manhattan project (1)

The Grim Reefer2 (1195989) | about 3 years ago | (#36887906)

It's a shame that the world is scared silly about anything nuclear now. I'd guess that projects like this [wikipedia.org] would be more feasible with modern reactor tech.

Re:Storage capacitor manhattan project (2)

MrEricSir (398214) | about 3 years ago | (#36888022)

The ghost of Osama Bin Laden is wetting his pants over this idea.

Re:Storage capacitor manhattan project (1)

localman57 (1340533) | about 3 years ago | (#36888220)

No, he just does that sometimes. Last week he was in the middle of shoveling a load of brimstone, and the same thing happened.

A storage technologyt is not needed. (1)

Shivetya (243324) | about 3 years ago | (#36888040)

A safe compact limited need to fuel power source is needed and only one thing fits the bill, fusion. Current planes already give up an immense amount of their weight for fuel so why would we want to continue that practice? If we are going to break from fossil fueled aviation then go all out.

Re:A storage technologyt is not needed. (0)

Anonymous Coward | about 3 years ago | (#36888436)

"A safe compact limited need to fuel power source is needed and only one thing fits the bill, fusion"

Since we have no such technology, how can you state that it'll be safe, much less compact? Have you SEEN the size of ITER's DEMO?

"Current planes already give up an immense amount of their weight for fuel "

A 747's empty weight is 400000 pounds. There's room for 50000 gallons of fuel. That's 34000 pounds of fuel. The fully loaded weight of a 747 is close to 800000 pounds. How did you come up with the hyperbolic "immense"? Are you retarded?

You're probably a software moron. Look, mashing away at a keyboard for five hours to make a picture appear on a screen doesn't make you smart.

How can you say the stupid things you posted? How can you not be bothered to check basic facts?

Re:A storage technologyt is not needed. (2)

wagnerrp (1305589) | about 3 years ago | (#36889128)

Kerosene is around 6.7 pounds per gallon, meaning that 50000 gallons of fuel weighs around 335000 pounds, not 34000 pounds. Over 40% of the aircraft's loaded weight is spent in fuel.

How can you say the stupid things you posted? How can you not be bothered to check basic facts?

Re:Storage capacitor manhattan project (0)

Anonymous Coward | about 3 years ago | (#36888616)

Expect, we can't have Capacitor Manhattan Project. The key ingredient to the Manhattan project was that we knew for a fact that a Nucleus's divided from a neutron release an extra neutron. So we really knew where to start looking. For a Capacitor project to work we need to have some thing to start with and build the tech around it that will make it work. Maybe their is an idea out there that needs funding to make it commercial but I think business and investors would jump at any thing that looked remotely promising. There has to be some basic understanding or we'll just be stumbling around in the dark. Everyone in nuclear physics understood the basics for how an atomic bomb should work. Get a dense and large enough mass of fissile material together for long enough and kaboom. The only questions where what is the best material, how to obtain said material, and how to make it go kaboom. Also, efficiency wasn't more then an after thought.

Not in any practical sense (2)

jpmorgan (517966) | about 3 years ago | (#36887726)

Not in any practical sense. Weight is critically important in aviation, and kerosene has an order of magnitude higher specific energy than the best batteries.

http://en.wikipedia.org/wiki/Energy_density#Energy_densities_ignoring_external_components [wikipedia.org]

Every pound counts (1)

Quila (201335) | about 3 years ago | (#36887776)

That's why airlines charge for luggage now.

If you could do the whole trip on battery, it's going to take many, many tons of batteries -- far more than fuel as you said -- and depending on your electricity generation source you could be putting out more pollution in the end anyway.

If it augments fuel in a hybrid configuration, then every pound of battery makes you burn fuel faster. Where are the savings? You don't get to do regenerative braking either.

Re:Every pound counts (0)

Anonymous Coward | about 3 years ago | (#36887834)

Yeah, but you can cover the wings with solar cells.

(Yes, I'm joking. It would help, but not much.)

Re:Every pound counts (1)

TheRaven64 (641858) | about 3 years ago | (#36888098)

Depends on the aircraft. For a light aircraft, you could get about 1kW in typical usage, assuming about 5 square metres of wing surface that are useable. Let's see what that would do with a Cessna 140:

Mass is 658 kg, fully fuelled, and the maximum rate of climb is 3.5m/s. Assuming 100% efficiency, that would require about 20kW, but at practical levels, it's much more - probably close to the 63kW maximum output of the engine. However, in straight and level flight, the energy requirements for an aircraft are pretty small. After takeoff, that 1kW may not be enough to completely power you at cruising speed, but it should go a long way towards it. There are some ultralight aircraft that can already fly for over a day just on solar power. I'd be quite interested in something in the middle, that could recharge on the ground during a sunny day and could cruise on solar power for longer than I'd want to stay alert for.

Re:Every pound counts (2)

vijayiyer (728590) | about 3 years ago | (#36888742)

A typical aircraft economy cruise is 55% of peak power. Fast cruise is 75% power. 1 kW would not go all that long of a ways towards powering the aircraft. Also, while the 140 is a beautiful aircraft, it's not exactly a speed demon.

Re:Every pound counts (0)

Anonymous Coward | about 3 years ago | (#36887840)

You don't get to do regenerative braking either.
That depends on if the regenerative things are better than the lift being produced on the plane. But yes batteries would be stupid huge... Now however think about this most locomotives made these days are actually electrical. With a huge diesel engine producing the power. Also you could use standard diesel instead of jet fuel. Also if the conversion is less than what a jet produces than electricity into a motor it may work...

Re:Every pound counts (1)

Baloroth (2370816) | about 3 years ago | (#36888166)

The difference is that locomotives have huge inertial mass, so they require massive power to get moving. Once moving, they require significantly less power to stay in motion, courtesy of the laws of motion. Therefore, electric-hybrid makes sense: batteries provide the initial power, so you can build a smaller diesel than you would otherwise need. Larger jumbo-jets, on the other hand, pretty much fly like a brick with wings. They run at close to full power pretty much the whole flight (I think its actually 70-80%), pretty well negating the advantage to hybrid setups. Especially given the added weight of such a setup (negligible in cars/locomotives, huge in aircraft).

Re:Every pound counts (1)

hawguy (1600213) | about 3 years ago | (#36888352)

The difference is that locomotives have huge inertial mass, so they require massive power to get moving. Once moving, they require significantly less power to stay in motion, courtesy of the laws of motion. Therefore, electric-hybrid makes sense: batteries provide the initial power, so you can build a smaller diesel than you would otherwise need. .

I don't think diesel-electric locomotives use any battery power to power the drive wheels. The advantage of the electric motor is that it generates high torque at low-speed to get the locomotive started, with no change in gear ratio needed as it picks up speed. The diesel engine driving the generator gets to run at its optimal speed regardless of how fast the locomotive is going.

Re:Every pound counts (1)

Grishnakh (216268) | about 3 years ago | (#36888866)

Hybrid technology is pretty much useless in aviation. Hybrid powertrains add a lot of weight to cars, so there's a tradeoff there. There's two primary reasons to use hybrid technology:

1) to recapture energy lost during braking. This is why hybrid cars have city mileage figures close to or sometimes better than highway figures, unlike regular cars where there's a big difference. Cars in the city waste a lot of power accelerating to speed, and then using the brakes to exhaust all that potential energy as heat so you can stop for a red light. Hybrids recapture a lot of this energy, and reuse it in the electric motor the next time you accelerate.

2) to allow you to use a smaller gas/diesel engine than you normally would, by getting an acceleration boost from the electric motor. A smaller ICE engine means lower pumping losses which means better fuel efficiency. So instead of sizing your engine so you get a good 0-60 time, you can size it so it has enough power to cruise on the freeway (plus extra for passing), and at low speeds the boost from the electric motor keeps your 0-60 time from being too ridiculously slow. The fundamental property here is that the power needed for 0-60 acceleration is much, much more than the power needed for freeway cruising at speeds under 100mph, so hybrids take advantage of this.

These factors simply don't apply in aircraft. 1) there is no braking in aircraft. You takeoff, then you fly somewhere, then you land and turn it off. There's no start-stop cycles like in cars, and there's no brakes (except for taxiing). 2) the power you need for cruising in airplanes is nearly as much as you need for takeoff, usually about 80%. That's not enough of a difference to make the extra weight of a hybrid powertrain worth it. In helicopters, it's worse: the cruising power is 100% of the takeoff power. Aircraft engines are very different from car engines, as they're designed to run at 100% output constantly. Most car engines would blow up if you did that.

Any time I read about someone talking about hybrid technology in aircraft, like in this article, I think it's just some kind of hype to get investor money and run off with it. We've seen this with lots of other vaporware technologies.

Let's do some numbers (1)

Quila (201335) | about 3 years ago | (#36888638)

I''m researching this as I go, so I don't know what the result will be, but I have a good guess.

Take the General Electric GE90, a powerful, efficient turbofan. It produces a wide range of thrusts, but I'll stick with the simple 500 kN near the top. It weighs 8,283 kg.

An EMD 710 diesel locomotive engine used in an efficient V20 configuration produces 3,098 kW and weighs 18,365 kg dry.

It obviously gets complicated from there because we're comparing power to thrust. How about, since you're thinking diesel-electric, I compare to a turboshaft? They're both rated in power, and both numbers would be converted to thrust in some manner, with whatever attending losses of the thrust system (propeller/ducted fan/etc.) being equal.

If you want fuel flexibility, the Honeywell AGT1500 from the M-1 tank can produce 1,120 kW running on, from what my tanker friends tell me, "greasy kid's stuff." However, it's not an aircraft design so it's quite heavy at 1,134 kg (for example, it sits in a heavy steel frame so it can be quickly plucked out to change engines).

So we use the later aviation version, the PLT27 that produces 1,434 kW and weighs 145 kg.

That's half the power at 1/127th the weight. No, diesels aren't going to work in airplanes. Far too low of a power/weight ratio. The equivalent weight in turbines would give you 182,118 kW, or almost a quarter-million horsepower.

Why do we still use diesels in locomotives then? The diesel is more reliable, long-lived and requires less maintenance. We don't care so much about an extra dozen tons since it doesn't matter much when it gets up to speed.

Re:Every pound counts (1)

Bob the Super Hamste (1152367) | about 3 years ago | (#36887882)

I have often wondered if I could fill my carry on with some really dense material, enough so that I can lift it but would exceed their weight limit for carry on and still have all the stuff I need for my trip as they never seem to check that. I think the whole checked luggage thing is more of a way for them to artificially lower their prices, it seems reasonable to have 1 free checked bag per person, but the we'll charge you for any checked bags is a scam, just include it in the price. Nothing is worse than the idiot who is trying to stuff their oversize duffel bag in the overhead compartment and not break things. Since my carry on has hard sides I put mine in the same compartment as theirs and make it fit, usually I don't stop until I hear something break.

Re:Every pound counts (1)

vlm (69642) | about 3 years ago | (#36888014)

I think the whole checked luggage thing is more of a way for them to artificially lower their prices.

Also baggage fees are not taxed / not taxed at the same rate as passenger fees.

They should simplify it and if you're willing to carry it, its free, and if you want to check it, you pay "UPS" "Fedex" airmail type rate. That also gets them out of the lost luggage problem. Especially on a return trip, I'd be more than willing to go "UPS ground" to my house and save them the cost of airmail and save me the time of picking the bags up.

Re:Every pound counts (0)

Anonymous Coward | about 3 years ago | (#36888936)

That's actually a rather interesting suggestion, though I suspect they would need to make some rate adjustments - $300 to have the first bag overnight-ed won't fly with travelers. I'm also not sure whether having a giant FedEx/UPS pickup location at the airport would be pleasant either - some people could ship things directly to their final destination, but I've stayed at many hotels that I would not trust to look after my luggage. Nor would I imagine that midsize hotels would be happy receiving 40-50 suitcases daily. I admit that seeing a semi truck full of luggage pull up to one of the big NYC hotels would be fun though.

Re:Every pound counts (1)

YrWrstNtmr (564987) | about 3 years ago | (#36888058)

I have often wondered if I could fill my carry on with some really dense material, enough so that I can lift it but would exceed their weight limit for carry on and still have all the stuff I need for my trip as they never seem to check that.

And you want to put this in the flimsy plastic bin over my head? No thank you.

Re:Every pound counts (0)

Anonymous Coward | about 3 years ago | (#36889186)

and he should care, as long as it isn't over his head?

Re:Every pound counts (1)

hawguy (1600213) | about 3 years ago | (#36888490)

Nothing is worse than the idiot who is trying to stuff their oversize duffel bag in the overhead compartment and not break things. Since my carry on has hard sides I put mine in the same compartment as theirs and make it fit, usually I don't stop until I hear something break.

Gee and my pet peeve is when I put my modestly sized soft-sided carry-on into the overhead bin, and then someone comes in with a hardsided bag and tries to shove it into the already full bin, crushing my bag and any fragile contents I've carefully packed int he middle of my clothes. (like that bag of pretzels that now becomes pretzel dust)

The thing I hate most about the hard-sided luggage is that it uses the same space whether it's half full or completely full, taking up more room than it needs to. Plus, when you get several of them side-by-side in a bin, you often end up with 6" of unusable space to the sides because they aren't sized to fit perfectly into the compartment. And when one is too big to slide longways, there's no hope of getting the door closed, you have to turn it around sideways, taking up twice the room. When a softsided bag is slightly too long, you can just scrunch it up a a bit and get the door to close (of course, crushing your pretzels)

Re:Every pound counts (1)

hawguy (1600213) | about 3 years ago | (#36888554)

I have often wondered if I could fill my carry on with some really dense material, enough so that I can lift it but would exceed their weight limit for carry on and still have all the stuff I need for my trip as they never seem to check that.

I don't understand why you'd want to do that? To force them to gate check it? On most full flights I've been on lately, they gate-check any carryons for free because they don't want delays while people try to shove too many bags into overstuffed overhead bins.

If you just want to make your bag heavy, bring some empty collapsible water bladders like you'd use for hiking then fill them after you're past security - 6 gallons of water will give you about 50 lbs of weight.

See what an economy-class meal used to be (1)

Quila (201335) | about 3 years ago | (#36888712)

Scroll down

http://www.everythingpanam.com/1960_-_1970.html [everythingpanam.com]

Re:See what an economy-class meal used to be (1)

Jeremi (14640) | about 3 years ago | (#36889182)

OTOH, also take note of what an economy-class plane ticket used to cost. (Adjust for inflation, of course)

Re:Not in any practical sense (2)

lyml (1200795) | about 3 years ago | (#36888118)

While what you're saying is true (that todays batteries are not energy dense enough). There are other advantages to a purely electric battery system making energy density not the only factor.

1. Higher efficiency of electric motors
2. Lower cost of fuel
3. Lower weight of electric motors

In fact, the article mentions that before it would be feasible to replace fuel with batteries for heavy aircraft battery capacity needs to increase by a factor of 4. When it does the switch-over would be fast due to the very high costs of flying air-planes.

In the meantime, we will have to settle for ultra-light airplanes using battery systems and watch as it becomes feasible for heavier and heavier aircrafts over time.

Re:Not in any practical sense (0)

Grishnakh (216268) | about 3 years ago | (#36888934)

Electric motors aren't lower weight; all that copper adds up. I'm quite sure if you tried to build an electric motor with the same power output as a modern turbofan jet engine, it would weigh much, much more.

If you're comparing to piston engines, then yes the electric motor probably wins pretty easily, but not compared to a jet engine.

Also, I think the factor of 4 number is ridiculously optimistic. Try a factor of 10, as that's roughly the difference between the energy-per-weight of jet fuel versus the very best modern batteries. If you could get batteries 4x better than today's, you might start seeing some small electric planes with very limited range, but that's going to make zero difference to most commercial aviation.

Re:Not in any practical sense (1)

91degrees (207121) | about 3 years ago | (#36888366)

From the article it sounds like the plan was to use a standard engine as a generator. Not sure if that's a huge advantage to be honest.

Of course other possibilities are fuel cells, or developing some form of wireless energy transfer (but I suspect the FAA would have issues over this solution and it would require a lot of infrastructure)

Electric may be safer (0)

Anonymous Coward | about 3 years ago | (#36887742)

Batteries don't exactly behave like a bomb on impact. It could even be painted with an energy-creating material [physorg.com] . Since there's no shade at 30,000' it should do well.

Re:Electric may be safer (0)

Anonymous Coward | about 3 years ago | (#36887926)

It could be a short-circuit away from an explosion.

Re:Electric may be safer (1)

MrEricSir (398214) | about 3 years ago | (#36888078)

No, batteries behave like a bomb even under normal use. Remember the rash of exploding laptop batteries a few years ago?

Chances are any form of energy crammed into a tiny space that can be easily converted to electricity has some inherent danger to it.

Wake me up (0)

Anonymous Coward | about 3 years ago | (#36887762)

when lead balloons become economically feasible.

SmartFish (1)

o'reor (581921) | about 3 years ago | (#36887808)

This electric plane [smartfish.ch] looks promising too, even though it's only a model airplane so far. Not sure there are many partners interested though...

Hovering Vehicle (0)

hantarto (2421914) | about 3 years ago | (#36887822)

A couple of years ago, I had an idea of making the hovering vehicle. I had fun in designing it. But an expert said that it can fly but requires a lot of energy.

This design is for creating hover vehicle that meet these criteria :
1. do not cause air blow,
2. have compact size,
3. VTOL flight,
4. able to stand still in the air,
5. do not have ground effect.

To be able to meet all the criteria above, we must be able to create a lifter system that lies inside the vehicle. And this lifter system must not affect the condition outside the vehicle (especially the air).

Since the lifter system must be able to lift the vehicle, so there must be part of the lifter system that is free/separated from the vehicle. Let us call it bullet. The bullet has to be shot horizontally, so that it won't affect the height of the vehicle's flying. The bullet has to be collided to a slope, so that the horizontal moving bullet can cause lift force.

Imagine a slope that can move up/down only (vertical movement only).

If the slope is collided by an inert bullet, the slope will go up, since the inert bullet tries to run as straight as possible. The slope is lifted, with the height of dh.

If the slope is shot once, the slope will be up and then fall.

So that the shoot must be done periodically, so that the height of the vehicle's flying will be constant.

To raise the height of the vehicle's flying, it can be done by : raising the force of the bullet, or raising the frequency of shooting.
Since the lifter system and the bullet must be inside the vehicle, so the bullet that has been shot is not permitted to be out of the vehicle. So we must be able to create a bullet puller mechanism. The bullet puller mechanism will place the bullet in its pocket, so that the bullet can be reshot.

We see unbalance condition, so we must balance it.

For the space balance, it needs three lifter systems that separated 120 degree horizontally.
A periode of shooting is the time of shooting needed to keep the height of the vehicle's flying constant.

A bullet cycle is the time needed by the bullet to move from its pocket, collides the slope, and back to its pocket.

If a bullet cycle is more that the periode of shooting, it's needed number of guns/bullets, so that the periode of shooting is reached.

If the force of the left bullet is bigger than the force of the right bullet, the vehicle will move to right. This is the way to move the vehicle forward/backward/turn direction.

The lifter system can be placed inside the vehicle.

This is the basic of my idea : "the horizontal moving bullet collides the slope".

What do you think?

Re:Hovering Vehicle (4, Insightful)

JustinOpinion (1246824) | about 3 years ago | (#36888020)

What you're describing will not work. You're trying to violate the laws of physics, similar to proposals of perpetual motion machines. It's a neat thought experiment, in order to identify the problems, but it won't work in the real world.

From basic Newtonian mechanics, we know that for every force there will be an equal and opposite reactive force. A closed system will not be able to achieve motion without an external force: either a force applied to other objects (e.g. pushing against the ground, or pushing against (a.k.a. 'blowing') a fluid like air or water) or by ejecting matter (as in a rocket).

Specifically regarding your design: As I understand it, you basically want an object where internally forces are applied to inclined planes, in order to push the planes 'upwards'. You imagine that this can be done in a way where there is no corresponding opposing force also pushing the object downwards. You try to get around this problem by imagining a decoupling where internal masses are momentarily not touching the main mass: so you have one piece that fires a 'bullet' horizontally, which hits the inclined plane (pushing it upwards). You imply that this means there is no corresponding opposing force. However you mention offhand that you will recover the 'bullets' and reuse them. But if the bullet hits the inclined plane, and pushes it upwards, then the bullet will be correspondingly deflected downwards. When the bullet hits the recovery mechanism, it will impart to it a downward force equal and opposite to the upward force that the inclined plane felt. The two forces will cancel out: the plane is pushed up, the recover mechanism is pushed down.

You can imagine putting the recovery mechanism further away from the inclined plane. But, at best this just creates a time lag between when the inclined plane is pushed upwards, and the bullet-recovery mechanism is pushed downwards. So the vehicle will jolt up-down but on average will stay in the same place and thus will not hover against the constant force of gravity. This is inescapable since the planes and the recovery mechanism are mechanically coupled to one another. The only way to solve this is to remove the recovery mechanism, and let the bullets shoot out the bottom of the object, so that the planes are pushed upwards and the opposing force is carried away by the bullets, out of the object. Of course 'flying' by shooting a gun downwards is generally inefficient, which is why we've invented things like helicopters, which push air downwards instead. That way you don't have to carry around a bunch of bullets; you just use the mass and hydrodynamic properties of the fluid you're flying through.

Have you SEEN the ultralight? (0)

Anonymous Coward | about 3 years ago | (#36887858)

Its a French-designed twin-engine plane called the "Cri-Cri" [geblogs.com] (picture link from the article above). Its so quirkily French that you can smell the stench of Gauloises in its slipstream.....

Man that's one long flight! (1)

flibbidyfloo (451053) | about 3 years ago | (#36887916)

"A battery electric-powered ultralight aircraft has been flying for the last year."

    And boy, are its batteries tired!

Re:Man that's one long flight! (1)

ArsonSmith (13997) | about 3 years ago | (#36888114)

Two drums and a symbol fall of a cliff....

bump bump ching

Realistically, it will be decades... (1)

Koreantoast (527520) | about 3 years ago | (#36888034)

The opening post implies that this electric aircraft revolution is right around the corner, but in reality, it will be decades before any practical implementation by any major aerospace company; I would dare say the 20-30 years the article estimates may be a bit generous. Weight is one of the biggest drivers in aircraft design (and one of the biggest factors of aircraft fuel efficiency), and until they can develop batteries with sufficient power to offset their massive weight, these planes will continue to be limited to small hobby craft. Nothing in this article indicates that these technological barriers have been overcome yet.

Even if the technology were all in place today, it would take a good five to ten years to design and certify a cargo or passenger aircraft. I'm hopeful with this technology, but I temper that hope with the reality of implementation.

thi5 FP for GNAA (-1)

Anonymous Coward | about 3 years ago | (#36888126)

Are electric planes even legal? (1)

BetterSense (1398915) | about 3 years ago | (#36888278)

It's been a while since I left the airplane scene, but from what I remember, the FAA requires small-engine airplanes to have reciprocating engines.

I've never seen a reciprocating electric motor, so are electric airplanes even legal?

Re:Are electric planes even legal? (1)

onkelonkel (560274) | about 3 years ago | (#36888372)

Why can't they have rotary engines or turbines?

Re:Are electric planes even legal? (1)

Grishnakh (216268) | about 3 years ago | (#36888982)

Some of them do. There's no such requirement, the parent is ignorant. Lots of people have made experimental aircraft with Mazda rotary engines, and I've seen small homebuilt helicopters with tiny turbine engines. The Robinson R-66 helicopter just came out which has a turbine, and that's a production craft.

Re:Are electric planes even legal? (1)

vijayiyer (728590) | about 3 years ago | (#36888786)

There are plenty of small aircraft with turbines, and small aircraft retrofits with turbines (Bonanzas, Cessna 210s, etc).

Re:Are electric planes even legal? (1)

robot_love (1089921) | about 3 years ago | (#36889138)

It's illegal in the same way that going faster than 8mph was illegal in cars a hundred years ago. Once the technology is proven, it won't be illegal anymore.

Slow down. (2)

MaWeiTao (908546) | about 3 years ago | (#36888314)

Of all the modes of transport available to humans, air travel would be hit hardest by a true fuel shortage. If we were to run out of oil in the next few years the we'd just transition to electric cars. Many, if not most, trains already run on electricity. There are alternatives for shipborne travel, coal, wind, nuclear and possibly even electric. There is, however, no viable alternative for air travel except for dirigibles. Unless, I suppose, someone were willing to give nuclear-powered aircraft a shot. Needless to say, intercontinental travel would get significantly slower for quite a while.

Re:Slow down. (2)

Grishnakh (216268) | about 3 years ago | (#36889180)

Many, if not most, trains already run on electricity.

No, they don't. They run on oil, just like everything else (diesel to be precise). They merely use a series-hybrid system so they can run the engine constantly and get much more torque than the diesel engine can generate. There's no batteries there. These systems have been in locomotives for many decades now, along with most large construction equipment.

Of course, since the actual propulsion is electric, you could power them from something else theoretically, but what? You need something to generate electricity. Batteries are out, because they don't store nearly enough energy to run a locomotive across the country. Mr. Fusion hasn't been invented yet. So you're stuck with some kind of ICE engine, running on either fossil fuel or biodiesel. Fossil fuel is much cheaper since you don't have to grow it, it's already made for you and waiting for you to pump it out of the ground. I suppose you could use coal somehow, but that isn't as energy-dense as fossil fuel, and it's quite dirty.

There are alternatives for shipborne travel, coal, wind, nuclear and possibly even electric.

Again, you have no idea what you're talking about. Many ships now are indeed electrically-propelled. But where do they get the power from? Diesel engines. Take away diesel and what are you going to use? Nuclear has only been used on one commercial ship in history, and it was a failure due to cost. There aren't exactly a lot of nuclear engineers out there willing to be paid peanuts to babysit nuclear reactors on commercial ships, and that isn't something you want some uneducated guy to be running; think about it: the people who serve as crews on ocean ships aren't usually normal middle-class people you'd trust with a multimillion dollar nuclear reactor where an accident means an environmental catastrophe (remember Japan just a couple months ago?), they're either guys with some screws loose, or desperately poor uneducated people from third-world countries. Nuclear power only works on military ships because the dynamics are completely different: rigorous training, unmatched benefits, the threat of court-martial if you screw up, a nation with the world's largest economy willing to spend a ridiculous sum of money on its military, etc. Nimitz-class carriers aren't cheap to operate.

If we ran out of oil, a lot of things would be very different, and I'm afraid it'd basically be like going back to the Dark Ages in many ways, unless some severe changes were made in time. Perhaps they'd build more nuclear power plants, and power the trains with overhead electric lines the way they do with light-rail systems, but that wouldn't help cars and ships much. They could probably use coal for ships somehow, though that would suck environmentally. They could probably do electric for cars, and everyone would just have to get used to a 50 or 75-mile range and recharging every night. If these things were put in place in time, disaster could be avoided, and we'd just have to make some adjustments to our lifestyles until new technologies (such as orbital solar power generation) could come online to give us cheaper and cleaner energy. However, seeing how political units work, I have little hope that they could avoid disaster.

Re:Slow down. (1)

prefec2 (875483) | about 3 years ago | (#36889192)

Indeed. However, we could transform the Trans-Siberia-Express route into a high speed train route. Ok we would still need twice the time to get to China. The transatlantic travel will fall back to 1940/1950 speed. But we will have Internet and so communication will be as fast as ever ;-)

Bad title (2)

bigsexyjoe (581721) | about 3 years ago | (#36888396)

The linked article does describe the efforts to create but it emphasizes that they need many advances to make it happen and that it isn't coming for at least twenty years.

Oil from coal is economical already (0)

Anonymous Coward | about 3 years ago | (#36888442)

Oil from coal synthesis is economical at $45 per barrel and the current oil price is double that. So if it wasn't for plentiful shale gas and enormous tar sands deposits keeping all the engineers busy, there would be oil from coal plants springing up everywhere.

So, oil isn't going to run out any time soon - not in the next 200 years or so anyway.

weight (1)

DaveGod (703167) | about 3 years ago | (#36888504)

I thought the primary problem with electric cars was the amount of power that can be stored for the weight of the batteries? Weight is an even more important issue for planes.

I would have thought batteries would need to be able to store twice (or thereabouts) the energy per kg since presumably they wont be allowed to jettison spent batteries. True aeroplane fuel is expensive but then it's saving costs on weight, something that also translates into emissions.

I guess the research is valuable regardless, but every time I hear about some electric vehicle the problem seems to always return to the batteries.

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