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New Electric Motor That’s Super Light and Powerful for Electric Airplanes
- ptaipale 10y agoI wouldn't think even older electric motors wouldn't work well enough in electric airplanes regarding weight and power? The weight of batteries is the biggest problem.
- thu 10y agoThere was this article[0] where they explain that light electric motors allow for new interesting design (e.g. in motor placement, and number of them). [0] http://spectrum.ieee.org/aerospace/aviation/how-i-designed-a-practical-electric-plane-for-nasa http://spectrum.ieee.org/aerospace/aviation/how-i-designed-a...
- SixSigma 10y agoHave an on board diesel generator
- jkot 10y agoLOL. Technically some heavy trucks and engines, are powered by electric motor with generator. Some of the biggest trucks and tanks were electric ;-) https://en.wikipedia.org/wiki/Diesel-electric_transmission https://en.wikipedia.org/wiki/Diesel-electric_transmission
- raverbashing 10y agoYou would use a turbine. Like the APU in existing aircraft
- Quequau 10y agoElectric airplanes already exist. Obviously they're not replacing long haul airliners this year... but not every plane is meant for that sort of use.
- ChuckMcM 10y agoJust penciling in the math that means a quad copter is pretty straight forward with this motor. 200kg for a "megawatt" of thrust. Now all we need are batteries that are 3x as power dense as the current best of class and you'll be able to hop from home to the office in your 'quad'.
- oconnore 10y agoWhy would you use batteries? Fuel gets lighter as you use it, and the density is already there. Automate maintenance so you can use turbines.
- ianpurton 10y agoMy guess would be electric might be simpler and easier to maintain and with electric you can charge at home.
- mtgx 10y agoMaintaining EVs is cheaper and easier than fuel-based vehicles.
- arca_vorago 10y agoI've thought the same thing, perhaps efficiencies for generating electricity for fuel engines are too low currently? Anyone have any stats?
- soundwave106 10y agoNot my area of expertise here, but since quadcopters are all about torque, I speculate that electric motors (with their flat-ish torque curve) are much easier to design for?
- ChuckMcM 10y agomass per kilowatt hour. That is the magic number. While a gas turbine can be slightly over 52% efficient it weighs a lot. You can plot weight over kilowatt hours, which is useful since at small numbers of kilowatt hours batteries are a huge win, and then at some point you get a cross over where the fact that fuel is more energy dense it has compensated for the weight of the turbine and generator infrastructure.
- ars 10y agoThis article has almost nothing about the actual motor in the title except this: "every component from previous motors was examined and optimized to lighten this motor and improve efficiency. The end-shield for the motor, for example, was analyzed using a software package that divided the component into over 100,000 elements, each of which was individually further stress-analyzed and subject to iterative improvement loops. Eventually, the custom software spat out a filigree structure that weighs 4.9kg instead of the 10.5kg from the previous design." The rest of the article is basically fluff with no info.
- Osiris30 10y agoAlready discussed at https://news.ycombinator.com/item?id=12060954 https://news.ycombinator.com/item?id=12060954 ... Some commenters had more info on the engine on this thread.
- emilong 10y agoTo what size of aircraft can a motor like this scale? Or perhaps more importantly, motor + batteries? To put it another way, is this technology likely to scale to an aircraft transporting 4 or more people anytime soon?
- ianpurton 10y agoAirbus are planning a 100 seater aircraft by around 2030.
- topbanana 10y agoIt's all about the batteries. That's what's holding us back
- sevenless 10y agoI'm starting to think good VR might do more to kill hydrocarbon consumption than electric vehicles. So many examples where moving meatbags around could be avoided altogether.
- Pamar 10y agoThis has been discussed here in depth: http://www.antipope.org/charlie/blog-static/2016/06/why-should-you-care-about-virt.html http://www.antipope.org/charlie/blog-static/2016/06/why-shou... (see the comments not just the main blog entry)
- intrasight 10y agoElectric engines doesn't necessarily mean batteries. Consider micro-turbogenerators. http://dukespace.lib.duke.edu/dspace/bitstream/handle/10161/3792/Camacho_duke_0066N_10953.pdf http://dukespace.lib.duke.edu/dspace/bitstream/handle/10161/... As others mentioned, fuel has the advantage of getting lighter over travel time. Also, electric motor planes should be wrapped with solar cells.
- JoeAltmaier 10y agoSolar cells add weight. As an energy source its hard to quantify them since they never run out, and weight the same the whole trip. Maybe more like batteries. Anyway energy/kilo is probably pretty bad. So for any finite trip, leave off the solar cells and use gasoline.
- mikeash 10y agoIt's easy to quantify solar cells on an airplane, just look at power consumed by propulsion and compare to power generated by the cells. The result is that the power generated is pretty much useless and doesn't even justify the weight of the solar cells, unless you design a plane to be extremely light and with nearly no payload, a la Solar Impulse. Solar could be good for drones that stay almost permanently airborne and just need to carry some electronics, but it's pretty much useless for transportation. If you must use electricity there, you'd want to use batteries on the plane, and keep your solar panels on the ground.
- oska 10y agoThe most recent episode of Fully Charged [1] looked at a 100% electric racing plane currently in development that uses two electric motors to drive two counter rotating propellers at the front of the aircraft. [1] https://www.youtube.com/watch?v=Xe1g1JrRRkY https://www.youtube.com/watch?v=Xe1g1JrRRkY
- elmar 10y agothe use case for this aircraft is to fly 20 minutes maximum so current battery technology power to weight is enough.
- usrusr 10y agoI applaud Siemens for venturing outside their comfort (profit?) zone instead of just incrementally improving whatever they did for decades already (and did not sell for having a bad quarter), but they are really overdoing milking this little plane for publicity. An electric motor being lighter, per Watt, than an ICE, who would have guessed. That being said, a hybrid setup could well be worth it, even with the abysmal specific energy density of real life batteries: keep just as much conventional engine as needed for cruise flight only and have some form of electrical assist for the few minutes of a flight that need more power than that. Battery density isn't a problem at all when you don't need endurance.
- phire 10y agoFor a hybrid setup, regulations will likely require that both the conventional engine and the electrical system to be powerful enough on their own to still take off if the other system fails after V1. Still, that's massive savings over the current twinjets, which require two engines, both powerful enough to take off after a failure of the other at V1.
- usrusr 10y agoSounds reasonable. But in an unlikely best case scenario, the electric part might somehow be certified for single engine reliability, capable of everything except endurance. A wave of comparatively liberal cruise engine development might then catch up with a few decades of combustion engine refinement.
- vlehto 10y agoSounds absolutely perfect idea for Eraknoplans. https://en.wikipedia.org/wiki/Ground_effect_vehicle https://en.wikipedia.org/wiki/Ground_effect_vehicle Typically these vehicles have 4X as much engine power for liftoff as they need for cruising. The reason is high water resistance and then very economical flight above the water body. Lift off being cancelled due to engine malfunction is less of a problem, as the "runway" is practically endless.
- elmar 10y agobetter articles WORLD-RECORD ELECTRIC MOTOR MAKES FIRST FLIGHT https://newshour.online/2016/07/04/world-record-electric-motor-makes-first-flight/ https://newshour.online/2016/07/04/world-record-electric-mot... Siemens' world-record electric aircraft motor punches above its weight http://www.gizmag.com/siemens-world-record-electric-motor-aircraft/37048/ http://www.gizmag.com/siemens-world-record-electric-motor-ai...
- userbinator 10y agoNothing at all about reliability, which is going to be the biggest factor the aerospace industry will be considering about this. You can sacrifice reliability for extreme power-to-weight ratio, as evidenced by things like Top Fuel dragsters and even the electric motors in RC planes are optimised more for power than longevity.
- tonmoy 10y agoSolar powered recon UAV with near unlimited flight time could be an application
- petra 10y agoJust combine some lighter-than-air structure with a UAV to achieve really great energy efficiency , and put solar panels on it. It would probably be possible in no-wind conditions to stay at the same point while charging the batteries.
- JoeAltmaier 10y agoI thought it was the battery, not the engine, that prevented long-distance flight? For energy / kilogram, lithium batteries are around 200 while gasoline is around 13,200.
- gambiting 10y agoYep - and as you use up fuel, your plane gets lighter, saving more fuel the longer you fly. With batteries, you have to carry the same weight for the duration of the flight. Which actually is a huge problem, because on most airplanes maximum take-off weight is higher than maximum landing weight.
- agumonkey 10y agoI have the stupidest idea. As energyless state fuel is released in the air, just drop 'depleted' battery modules and have them collected.
- JoeAltmaier 10y agostill the energy/weight ratio is > 60 times worse than gasoline. If you're not going to recharge them, then there's no remaining advantage to batteries
- agumonkey 10y agoCollect, centralize, recharge, reuse. Maybe have a solarimpulse battery carrier to distribute them while flying.
- Retric 10y agoMechanical simplicity. If your going to use fly by wire it's nice to have stored power to land without losing control in the event of total loss of fuel or massive mechanical failure. Though this is something like 1/10,000th of total energy used in flight it's really important.
- mikeash 10y ago
- swingbridge 10y agoA lighter engine certainly doesn't hurt, but it's really the batteries that are an issue. The other item often overlooked on the battery front is that most batteries hate the cold. Take your iPhone out on a 20F day and see how long that 100% charge lasts! (Spoiler alert, likely a few minutes). As you go up in the atmosphere things start to get really cold. Until the weight and temperature issues with batteries can be address electrical aviation will be mostly a concept on paper.
- Vexs 10y agoI'm curious if a heater coil gives better battery life or worse battery life in cold environments. Also, better batteries has been an issue forever. Electric cars were invented alongside the combustion car, but they didn't have good batteries, and died because of it.
- napoleond 10y agoHeater coil gives way worse battery life, but can still be useful to preserve other electronics in the cold.
- Retric 10y agoAssuming you start the flight from mains power it depends on volume. https://en.wikipedia.org/wiki/Gigantothermy https://en.wikipedia.org/wiki/Gigantothermy For a poorly insulated toy quadcopter it is a bad idea. Something, the size of a 747 might need active cooling. Between them there is a point where a little heating is probably a good idea.
- rolf123 10y agoIf the batter is working hard delivering power, it will generate some heat on it's own.
- napoleond 10y ago> Take your iPhone out on a 20F day and see how long that 100% charge lasts! (Spoiler alert, likely a few minutes). It's true that Lithium Ion batteries lose their charge in cold temperatures, but not that quickly. An iPhone in 20F will still hold charge for several hours. (And of course, under normal operating conditions the iPhone will be close to a warm human regardless of ambient temperature, so they rarely get that cold.)
- kragen 10y agoYou'd think that since the article is about how this motor is a new record in power density (or rather specific power), it would include the specific power in the article somewhere. You would be wrong, but it does include the information needed to calculate it. The SP260D motor they're talking about has a specific power of 260 kW / 50 kg = 5.2 kW/kg. It's not clear if this includes the weight of the batteries or not. The article says the usual motor for the Walter Extra 330L is 315 horsepower, which is 234 kW. The "E" in the model number "330LE" apparently refers to the electric version. To contextualize, motor specific power is actually really important for heavier-than-air flight. The reason Leonardo's helicopter designs wouldn't work is a lack of specific power in the (human) motors he had in mind, more than any aerodynamic reason. (Sufficiently high specific powers can overcome even remarkably poor aerodynamics.) The Wright brothers' main innovations were: a workable system for steering, and a motor with sufficiently high specific power. The bit about the motor's end shield seems to be describing topological optimization, but the description of the process is somewhat ambiguous. It would be nice to see a picture of the end shield and maybe information about how it's made. Maybe a less clueless, though even more information-scarce, article is http://www.flyingmag.com/extra-unveils-electric-330le http://www.flyingmag.com/extra-unveils-electric-330le Other commenters are pointing out that this won't work for long-distance flight. The Flying article I linked above says it will actually only last either 5 minutes or 15–20 minutes (it seems to contradict itself, but maybe I just don't understand it.) So it's adequate for aerobatics only. But it should be better at aerobatics than the standard engine was. Further links from other comments: https://news.ycombinator.com/item?id=12060954 https://news.ycombinator.com/item?id=12060954 http://www.gizmag.com/siemens-world-record-electric-motor-aircraft/37048/ http://www.gizmag.com/siemens-world-record-electric-motor-ai... https://newshour.online/2016/07/04/world-record-electric-motor-makes-first-flight/ https://newshour.online/2016/07/04/world-record-electric-mot...
- skykooler 10y ago> The Wright brothers' main innovations were: a workable system for steering, and a motor with sufficiently high specific power. And an airframe that could work with both of those. Langley, for example, had an engine that weighed about the same as the Wrights', but put out 50 horsepower to their 12. But the Aerodrome collapsed on takeoff, rendering that power useless. The Wrights had a mechanically simpler design that was strong enough to cope with aerodynamic forces.
- Pxtl 10y agoThis should be interesting for solar-powered remote-controlled aircraft, where battery weight is less of a concern.
- peter303 10y agoAs we approach the 200th anniversary of Faraday's 1821 invention of the electric motor, I am impressed we are wringing out improvements.
- saidajigumi 10y agoIt seems that this motor's power-to-weight ratio advantage applies just as well to ground vehicles. Are there reasons why that isn't the case? I.e. is this approach somehow specific to heavier-than-air engines? (Also, speaking not necessarily to using this specific motor, but rather applying Siemens' cited optimization techniques for ground applications.)