Why battery-powered aircraft will never have significant range

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Geraldc

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For anyone that has a bit of time here is a good article on what Pipistrel has achieved.
 

Vigilant1

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Tesla batteries weigh 6kg per kwh
Pipistrel uses two replaceable battery packs weighing 58 kg each
to give 21 kwh.
So about the same.
edited misread Pipistrel specs
And Pipistrel says the battery for the Alpha Electric lasts 300 to 700 cycles. That equates to a flight cost (battery cost only) of $30 - $75 per hour at Pipistrel's stated battery replacement part cost. The Rotax is cheaper to run even if we include fuel costs and Rotax rebuild reserve. And with the Rotax, you can actually fly somewhere.
 
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EzyBuildWing

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Electric Paramotor Technology...... Paramotors are always the"earliest-adopters" of very latest reliable light-weight battery-tech for flying-machines...... 45 minute flights..... see below:

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Rhino

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Tesla batteries weigh 6kg per kwh
So, 13 pounds to us non-metric types. That wouldn't be too bad a weight for swapping out, assuming that's the weight of a single battery.

Pipistrel uses two replaceable battery packs weighing 58 kg each
to give 21 kwh...
Wow. 128 pounds. Not something you'd want to swap out somewhere while traveling.
 

John.Roo

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2x 58 kg (2x 128 lb) battery is a bit too heavy for replacement.
And it would be easy only in Pipistrel Aplha Electro.
Pipistrel Velis has battery cooling system and it is certified (= it is necessary to have training and certificate to do that).

However there are possibilities how to do that...
Look here:
You can install 6x 15,5 kg battery pack with 3,5 kWh. In total is 21 kWh / 93 kg (205 lb) = bit lighter than Pipistrel battery packs, but without battery cooling system.
Each battery pack has independent BMS etc.
Another positive think is that you can add more packs to system if you need.

For example....
I fly with two persons aboars - it means I can use 6 packs to stay in MTOM.
I fly alone = I can have holder to add another 6 packs to have 42 kWh capacity.
In case I want to make training I can re-charge one set and fly with second set and quickly swap.
Of course is extra cost to have 12 batery packs, but it gives you more possibiities.

With 42 kWh battery I could imagine to make also glider aerotowing.
I tried aerotowing of one seat gliders with electric Phoenix with 35 kWh battery and it is possible.
e-aerotow on blue sky.jpg
 

John.Roo

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You can buy many different types of motors and controllers and BMS systems etc.
But than you will spent a lot of time trying to connect all together. It is a cheaper way, however no warranty and all risc is on your side.
Or you can buy "plug and pay" system like system from Geiger or like we use from MGM. Than you have warranty and technical support. All has been tested together so controller gets info from motor, from BMS, you have backed up throttle system, charger communicates with BMS etc. etc.
I tried both ways and beleive me - it is very far from reality to expect that you just connect parts from independent producers together end they work :) For my plane I can take a risc (it is adventure), for customer I need "plug and play" system with non-stop technical support.
It is great to have freedom of choice :)
 

ElectricFlyer

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tspear

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@Rhino

I updated my profile, I left Onieda in 2014 :) I forgot location was on this profile.
Anyway, based on survey data I have seen, and among friends/family very few road trip. It is largely reserved for very special occasions, e.g. wedding, baptism...
In fact I know a few couples where they have downsized from a large family SUV/Minivan to small sedans and rent the SUV/Minivan for the annual vacation. They specifically stated the savings in gas over a year pay for the car rental, and they have less money tied into the vehicle.

I highly doubt I will convince you otherwise based on your posts in this thread so far; regardless of the number of survey and research papers I find and point you too.

Tim
 

tallank

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And what was the chemistry of that battery? I'll guess LiPo. Now we have LiFe which are just as good and do not have the bad habits of LiPo.

I would not say batteries will never produce the range. They just don't do it now for most. But battery technology has advanced by leaps and bounds in recent years and there's some considerable advancements being worked right now. One technology promises 10 or more times the capacity for a given weight and physical size. That would put electric cars over 1000 miles per charge with some as high as 3000 miles.

Times are changing.
If there was a real new battery on the horizon it would be the hottest stock on NASDAQ. There are many new technologies being looked at in Universities but none have made it to market.
 

EzyBuildWing

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Paramotor tearing up the sky..... ....filmed by a very agile "chase-drone"...... vid is like what you see when playing an arcade-game!.....
Chase-drone can also be programmed to "front-fly" looking back....... WOW!
Open PPG offfers electric 1 hr Paramotor......quiet, smooth and $8k.
Electric aviation-possibilities are certainly opening up.

 

blane.c

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Paramotor tearing up the sky..... ....filmed by a very agile "chase-drone"...... vid is like what you see when playing an arcade-game!.....
Chase-drone can also be programmed to "front-fly" looking back....... WOW!
Open PPG offfers electric 1 hr Paramotor......quiet, smooth and $8k.
Electric aviation-possibilities are certainly opening up.

Dude is trolling for Crocs?
 

rv6ejguy

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You can install 6x 15,5 kg battery pack with 3,5 kWh. In total is 21 kWh / 93 kg (205 lb) = bit lighter than Pipistrel battery packs, but without battery cooling system.
This shows what the current state of battery technology is: 28hp for one hour requires 205 pounds of batteries. To equal 100 hp Rotax performance for 1 hour, requires 732 pounds of batteries, for 4 hours, 2928 pounds of batteries, if my math is correct. Multiply these weights by .75 to .8 for cruise flight approximately.
 

blane.c

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This shows what the current state of battery technology is: 28hp for one hour requires 205 pounds of batteries. To equal 100 hp Rotax performance for 1 hour, requires 732 pounds of batteries, for 4 hours, 2928 pounds of batteries, if my math is correct. Multiply these weights by .75 to .8 for cruise flight approximately.
Making a Desktop Fusion Reactor - YouTube
 

Vigilant1

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This shows what the current state of battery technology is: 28hp for one hour requires 205 pounds of batteries. To equal 100 hp Rotax performance for 1 hour, requires 732 pounds of batteries, for 4 hours, 2928 pounds of batteries, if my math is correct. Multiply these weights by .75 to .8 for cruise flight approximately.
Yep, and it is even worse than that. The 28 HP of electricity needs to be reduced by controller, cable, and motor losses to get power at the prop. High quality brushless DC motors max out at around 80-90% efficiency, and we lose about another 5% in the controller. So, our 28hp of electricity (21kw) yields less than 24hp at the prop hub.
And, as battery weight goes up for those longer flights, we need to account for the additional battery capacity needed to lift that bigger battery capacity. And the weight of the aircraft structure to support those heavy batteries. All that weight has to be lifted during climb and costs us in increased induced drag for every minute of cruise.
Reliability: Much talked about. Did we ever figure out why the Avinor CEO lost power in their Pipistrel electric airplane on the way to a VIP demonstration and crashed into a Norwegian pond? Equipment failure? Pilot error? Uncertainty in determining remaining 'fuel' in this electric airplane? The crash was more than 18 months ago, anybody seen the results of the investigation?
 
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Pops

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Where do people think all the electric power will be coming from, the Tooth Fairy . They want everything electric ( airplanes-autos) and don't want any more electric power plants built. I want a new Gulfstream 650 for Christmas this year. Didn't think about the money it takes to operate it. Everything will be OK , the Tooth Fairy will bring it.
 

Dan Thomas

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Where do people think all the electric power will be coming from, the Tooth Fairy . They want everything electric ( airplanes-autos) and don't want any more electric power plants built. I want a new Gulfstream 650 for Christmas this year. Didn't think about the money it takes to operate it. Everything will be OK , the Tooth Fairy will bring it.
A common problem. Schools teach all sorts of useless stuff now intead of real science, and the ignorance is pulling the society down. Lots of people don't even seem to know where their food comes from. It just appears on the supermarket shelf.
 
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