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Australia's first electric aircraft has begun test flights

abc.net.au

31–40 of 79 posts

Re: Australia's first electric aircraft has begun test flights

#31
post #26
post #25

Are there denser ways to store electrical energy? Hydrogen fuel cells maybe? Seems like you need something much lighter than lithium-ion batteries to even begin to fill the role of passenger planes.

Here are some comments from Musk regarding electric aircraft: https://www.youtube.com/watch?v=yx3auTD85Fw

"I'd love to do it... but I think my mind would explode."

Re: Australia's first electric aircraft has begun test flights

#33
post #20

Earlier quoted context omitted.

Coal power plants are roughly as efficient as an internal combustion engine (around 40%) and considering the power transmission losses, charging losses, electric engine inefficiencies and so on, any electric vehicle has worse overall efficiency than the equivalent gas vehicle. Electric vehicles only make sense from a pollution reduction point of view if the power is generated from renewable sources.

You would find it very hard, if not impossible, to run an ICE car at 40% efficient for normal driving. The same can not be said for a coal plant. So if the coal plant averages 35% and the ICE car averages 25%, that leaves some room for a coal-driven electric car to be more efficient. The conversion from grid power to mechanical power only needs to be over 70% efficient. If anything, that sounds easy to beat. Any coun…

I we say all three of: charging, motor controller and motor are about 90% efficient, that's already 72% efficiency from grid power to mechanical. So maybe not that easy.

Re: Australia's first electric aircraft has begun test flights

#34

Earlier quoted context omitted.

Coal power plants are roughly as efficient as an internal combustion engine (around 40%) and considering the power transmission losses, charging losses, electric engine inefficiencies and so on, any electric vehicle has worse overall efficiency than the equivalent gas vehicle. Electric vehicles only make sense from a pollution reduction point of view if the power is generated from renewable sources.

What's the power transmission loss from carrying crude to a refinery and then to Australia? The country is a net importer of oil, which means tankers burning foul stuff to carry it there.

Very true. Considering the whole supply chain for accurate comparison is complicated. Although I think my main point still stands : from an environmental perspective it's rather ineffective to have an electric car in a place where electricity comes from fossil fuels.

Re: Australia's first electric aircraft has begun test flights

#35

Earlier quoted context omitted.

What's the power transmission loss from carrying crude to a refinery and then to Australia? The country is a net importer of oil, which means tankers burning foul stuff to carry it there.

Very true. Considering the whole supply chain for accurate comparison is complicated. Although I think my main point still stands : from an environmental perspective it's rather ineffective to have an electric car in a place where electricity comes from fossil fuels.

I think you're overstating the current situation and also leaving out the fourth dimension. If the grid gets cleaner over the useful life of the EV then it benefits from that. I believe basically all grids are projected to get vleaner over the next decade.

Re: Australia's first electric aircraft has begun test flights

#36

Earlier quoted context omitted.

>Then what would you call the person in the second seat, who isn't flying the plane? Instructor. These are designed pretty much exclusively as LSA trainers.

Touring motor gliders are often sold to couples that want to travel together. I've known people who own/fly: Dimona H36 and Taifun 17E. I have a family member who recently purchased a TL Sting S4 (a microlight) for similar purposes.

Not this one. Pipistrel brings their planes to EAA Oshkosh every year and their internal combustion planes are marketed as touring motor gliders. But the electric Alpha Electro is just touted as a training plane because its range is so short.

Re: Australia's first electric aircraft has begun test flights

#38
post #19

"Australia's first electric passenger plane takes to the skies" Well, one passenger, more like a sports plane than an airliner. Still very awesome :D

Very cool, right? I had a brain fart when I read the title on the front page thinking it was a self-driving electric plane, for some odd reason, and my heart skipped a beat. >It costs about $3 an hour to run the plane's engine, one-tenth the cost of a fuel engine. This sounds really great and at only €65,000 ($78196.30USD) it sounds like a steal that will scale nicely once it can carry the 5+ passengers it intends to…

Where’s the €65,000 number coming from? I found http://www.flypipistrel.com/price-lists/PIPISTREL-ALPHA-ELEC... which suggests €159,000.

That datasheet also says 700 cycles to 75% battery capacity, rather than the “about 1,000” of this article.

The $3/hour figure doesn’t seem to me to match the other numbers, either: 60kW for takeoff and 20kW for cruising; let’s ignore takeoff (it’s rounding error) and just call it 20kW. 20kWh for $3? At residential rates, 20kWh will cost more like $5. But I don’t know what commercial rates are for electricity; maybe they do get power that much cheaper than residential persons.

Re: Australia's first electric aircraft has begun test flights

#39
Funny remark about it being silent. In the text they mention that it's silent when it's gliding. Well, duh... in the video they say it's just silent.

If you look up a video on youtube, you'll hear that the propeller still cause a lot of noise. So it's only more silent from the ground.

Re: Australia's first electric aircraft has begun test flights

#40
post #25

Are there denser ways to store electrical energy? Hydrogen fuel cells maybe? Seems like you need something much lighter than lithium-ion batteries to even begin to fill the role of passenger planes.

The tricky part with hydrogen is the containment. You either need cryogenically cooled tanks to get it to a liquid state, or metal hydrides to store it chemically. Both have fairly poor energy density (by volume and mass). What's more, the fuels cells aren't cheap either, and some of the more efficient ones operate at very high temperatures.

For all it's faults hydrocarbon fuels are really good at storing energy that's easily extractable.

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