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Science

The Electric Airplane Is Coming 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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The Electric Airplane Is Coming

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

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

      • 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 s

        • 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.
          • by Jeremi ( 14640 )

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

            Sure they can. ;^)

          • I didn't have to. The truth is that a 1 MW/h SMES weighs about as much as a horseshoe. To replace 81 kilos of jet fuel. It's *significantly* lighter. And then you get to rip off a lot of parts of the plane as generally useless and just use a much smaller electric engines. And I calculated it for a 747, rather than any other plane. I'm already using much less weight it's fine. The average weight of the fuel is much less than with the jet fuel. And the values I used for jet-fuel were the averages already so i

            • The truth is that a 1 MW/h SMES weighs about as much as a horseshoe.

              MW/h. You keep using that word. I do not think it means what you think it means.

              none of which I bothered to take into account, because they only help my case.

              Nothing can help your case if you can't keep your god damned units straight. It makes you look like someone who is just regurgitating crap they read off some internet webring, without understanding any of its implications.

    • by antdude ( 79039 )

      Why were you using dial-up Internet? ;)

    • A missing carrier can be a serious problem for a plane.

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

      • 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 lo
        • by vlm ( 69642 )

          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.

          • 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?
            • Exactly. Anything hard and solid that makes it through the combustor will tear up a high pressure turbine.
          • 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.
        • by afidel ( 530433 )
          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.
          • 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.
            • by afidel ( 530433 )
              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.
              • 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 no
                • ...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 kn

              • by ryanov ( 193048 )

                What is wrong with using canned or jarred vegetables?

                • by afidel ( 530433 )
                  The flavor and texture suck compared to fresh and they normally use salt as a preservative which I need to avoid over-consumption of.
                • 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.
      • 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.
        • I always saw the fact that fossil fuels are the only practical fuel for large aircraft as an argument to reduce oil use. If it gets too expensive before we improve battery tech to the point that it can power large aircraft then we're going to hit a big air travel crunch. No point wasting the oil in cars that could just as easily run on electricity from some other source.

      • But... they showed this beautiful model! You know, made on a computer! Shiny and everything! So this thing must be basically finished, right?
    • 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 chemic
      • by lyml ( 1200795 )

        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 al

        • 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 sim

          • by lyml ( 1200795 )

            I agree with you, battery technology is the problem holding back widespread adoption of electric vehicles. However, for some applications, mopeds, short-distance automobiles and ultra-light aircraft (the articles example) battery technology has already reached sufficient capacity (and those application will use predominantly battery technology once economies of scale kicks in, it has already happened with mopeds).

            Though an order of magnitude more capacity is far more capacity than needed. Currently the most

    • by aevan ( 903814 )
      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).
    • Yes, they now run on atoms and stuff.

    • by prefec2 ( 875483 )

      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.

  • The personal flying car is here.

  • by localman57 ( 1340533 ) on Tuesday July 26, 2011 @02:55PM (#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!

    • by vlm ( 69642 )

      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]

    • My Volt only goes 35 miles

      Sucker! Just wait until you have to replace those batteries because it only holds a charge for a measly mile.

  • by xtal ( 49134 ) on Tuesday July 26, 2011 @02:58PM (#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.

    • by Jeng ( 926980 )

      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?

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

    • 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.

    • by Ihmhi ( 1206036 )

      You can't blow up an entire country with a storage capacitor, and that's why a project (that is so greatly needed) will never get that sort of funding.

      The only way you'd get enough money to get significant research on a good storage capacitor was if you were in Texas and it came attached to a chair.

    • by Teancum ( 67324 )

      Just what we need.... a multi-billion dollar project that literally flushes away money like there is no tomorrow. It turns out that the Manhattan Project wasn't nearly so desperate either and it would have been interesting to see how World War II might have ended had it not gone one. Certainly it turns out that Germany was so far behind in nuclear physics research that the entire concept of a nuclear bomb was merely an afterthought by the time the Manhattan Project was completed.

      The other problem is that

  • by jpmorgan ( 517966 ) on Tuesday July 26, 2011 @03:01PM (#36887726) Homepage

    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]

    • 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.

      • 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 tha
        • by vlm ( 69642 )

          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.

        • 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.
        • by hawguy ( 1600213 )

          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, w

        • by hawguy ( 1600213 )

          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.

          • by Jeremi ( 14640 )

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

    • by lyml ( 1200795 )

      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 ve

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

        And boy, are its batteries tired!

  • 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?
    • Why can't they have rotary engines or turbines?
      • 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.

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

    • 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.

  • by MaWeiTao ( 908546 ) on Tuesday July 26, 2011 @04:05PM (#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.

    • 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 theore

      • by ErikZ ( 55491 ) *

        We will never "Run out of oil".

        It's remarkably easy to make more, just using sunlight, water, and genetically engineered microbes.

        • by bertok ( 226922 )

          Sure, energy is fungible.

          The problem is that all such methods add a substantial overhead in terms of % loss of energy and as a significant infrastructure expense. For example, it's surprisingly hard to expose microbes to sunlight without fouling issues, or contamination from other microbes. A lot of trivial demonstrations have been done, but a small, short-term project that isn't intended to make a profit is a far cry from doing this on an industrial scale, where the people operating the system are poorly e

      • No, they don't. They run on oil, just like everything else (diesel to be precise).

        Afaict this varies a lot by country. In france for example the majority of railways are electrified while in germany about half are and in the UK just under a third is and afaict in the USA very few railways are electrified.

        Of course oil won't just suddenly "run out". Production will decline and prices will go up as sources gradually dry up. The question is will that rise come slowly enough for society to adapt. Another major concern is that environmental damage from the fossil fuel industry is likely to in

        • Afaict this varies a lot by country. In france for example the majority of railways are electrified while in germany about half are and in the UK just under a third is and afaict in the USA very few railways are electrified.

          Sorry, my American bias was showing. Here in the USA, we don't have any passenger rail to speak of (Amtrak is lame), so when he said "trains", I immediately thought of freight trains. AFAIK, all freight trains use diesel-electric propulsion. I don't know for sure, but I would imagine

          • AFAIK, all freight trains use diesel-electric propulsion. I don't know for sure, but I would imagine that the power demands of a freight locomotive would be too high for the type of electrification you see on light-rail or the European-style passenger rail systems.

            I've definately seen electric locomotives runnining off the 25KV overhead lines we have round here (manchester, UK) pulling freight trains. They probablly aren't as big as the american freight trains though.

    • by prefec2 ( 875483 )

      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 ;-)

  • by bigsexyjoe ( 581721 ) on Tuesday July 26, 2011 @04:16PM (#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.
  • 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 e

  • The thing that's most spectacular is that the regenerative braking means you'll never hit the ground in a fall!

  • Commercially, I don't see batteries working, simply because it would affect the turnaround time of aircraft drastically, an aircraft on the tarmac charging it's batteries is an aircraft that is not making money.

  • It is easy to create a picture of a cool craft [nocookie.net] based on technology that does not exist yet. The trick is in implementing the technology.

Statistics means never having to say you're certain.

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