All electric commuter (9 pax) aircraft
06-23-2019, 04:47 PM
#21
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Originally Posted by pangolin
There's other ways to store power and to generate power. A large capacitor is one way but I don't know about the weight and controlled release or stored energy.
Fuel cell for generating electric power is a possibility as well.
Fuel cell for generating electric power is a possibility as well.
Technology often starts slowly with a new tech discovery, ramps dramatically, but then hits an asymptote. Look at cruise speeds of airliners...no real change since the B707, because the speed of sound is an immutable fact, as is the scientific fact that speed BEYOND Mach 1 always takes more energy than subsonic flight. Oh, you might find new technologies such as refined airfoils, materials, and engines to make supersonic more efficient than before...but a subsonic airplane will always be more efficient than a supersonic. Just physics....and chemistry.
The same with batteries and electrics. It’s about energy density, and there is no foreseeable technology, given the scientific facts, that could make them compete on a density basis with liquid fuels.
California’s recent legislation to become “emission-free” in less than 20 years is not based on any scientific or engineering principle, but rather, on good-intentions, well-wishes, and pixie dust. It’s as achievable as their low-cost job-creating high-speed rail.
Oh wait....
06-23-2019, 04:47 PM
#22
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Joined APC: May 2010
Position: Baja Vermont
Posts: 5,177
Fuel cells have been the emerging power generation for 55 years and no closer to civilian feasibility now than on Gemini flights.
Pilots, who should know better, keep believing warp drive is just around the corner. And J.C. Whitney has a carburetor that gets 50 mpg but the oil companies killed it, Right!
GF
Pilots, who should know better, keep believing warp drive is just around the corner. And J.C. Whitney has a carburetor that gets 50 mpg but the oil companies killed it, Right!
GF
06-23-2019, 08:22 PM
#23
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Joined APC: Mar 2007
Position: Capt
Posts: 3,215
Originally Posted by rickair7777
No. No possible battery chemistry can provide the required energy density/specific energy. Chemistry is a very mature science, we're not going to suddenly find a new molecular structure when can store ten times the energy.
All we can do with batteries is improve the efficiency of known chemistry towards the theoretical max. Also improve cycle life and charge cycle degradation characteristics.
Right now mature (commercially viable) battery technology can get to around 200 W hours/KG. Theoretical chemical limit is about 1,000 Wh/KG.
Jet A is 12,000 Wh/KG...
There's no uncharted territory in molecular chemistry which is going to provide an order of magnitude+ improvement in specific energy. The answer is going too be biofuel.
All we can do with batteries is improve the efficiency of known chemistry towards the theoretical max. Also improve cycle life and charge cycle degradation characteristics.
Right now mature (commercially viable) battery technology can get to around 200 W hours/KG. Theoretical chemical limit is about 1,000 Wh/KG.
Jet A is 12,000 Wh/KG...
There's no uncharted territory in molecular chemistry which is going to provide an order of magnitude+ improvement in specific energy. The answer is going too be biofuel.
"I've also seen references on the internet to Li/O2 and Al/O2 batteries with MTSE of 2815 and 5200 Wh/kg"
"Using complex hydrides, a research group in Japan has demonstrated the possibility of building high-energy-density all-solid-state batteries with capacity exceeding 2,500 Wh/kg. Read more from Asian Scientist Magazine at: https://www.asianscientist.com/2019/04/in-the-lab/solid-state-lithium-batteries-complex-hydride/"
06-23-2019, 08:27 PM
#24
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Joined APC: Mar 2007
Position: Capt
Posts: 3,215
Originally Posted by Excargodog
Cheaper - by far - to just use fossil fuel and offset the carbon release with carbon capture technology. Doubt that will change in the next several decades, at least not without a hellacious capital investment that would take even more decades to recover.
Or build a nuke power plant and count the natural gas you are NOT burning as recapture.
Or build a nuke power plant and count the natural gas you are NOT burning as recapture.
06-23-2019, 08:29 PM
#25
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Joined APC: Mar 2007
Position: Capt
Posts: 3,215
Originally Posted by FlyJSH
Just where are we going to get all the electricity required to recharge all these "zero emission" vehicles? Currently (no pun intended) the US gets electricity from: (percentages are approximate)
Clean burning natural gas - 34%
A 500 year supply of coal - 30%
Evil, environment destroying nuclear - 20%
Snail Darter killing hydroelectric - 6%
Migratory bird killing wind -5%
And everything else - 4%
There are not many more places to put hydro dams, wind farm locations are becoming harder to find, and 'everything else' is tapped out too.
Our Sun is soon to go supernova???
If one does the math for gasoline, the US would need to increase electricity production about 120% to replace auto fuel. And since every time energy is converted from one form to another efficiency is lost, that 120% is probably more like 150%.
Ahhhh, zero emissions!
Clean burning natural gas - 34%
A 500 year supply of coal - 30%
Evil, environment destroying nuclear - 20%
Snail Darter killing hydroelectric - 6%
Migratory bird killing wind -5%
And everything else - 4%
There are not many more places to put hydro dams, wind farm locations are becoming harder to find, and 'everything else' is tapped out too.
Our Sun is soon to go supernova???
If one does the math for gasoline, the US would need to increase electricity production about 120% to replace auto fuel. And since every time energy is converted from one form to another efficiency is lost, that 120% is probably more like 150%.
Ahhhh, zero emissions!
06-23-2019, 08:52 PM
#27
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Joined APC: Mar 2007
Position: Capt
Posts: 3,215
Originally Posted by BobZ
Dz that include the co2 expelling humanoid heat engine?
Shortly thrs gona be 10 billion of them polluting the planet.
Shortly thrs gona be 10 billion of them polluting the planet.
Almost all of our major problems, including the Climate Crisis, are caused, or exacerbated, by having too many people on Our Earth...
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