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EV-6A: A Thought Experiment

ssokol

Well Known Member
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This morning I read yet another article in the aviation trades talking about the failure to find a drop-in replacement for 100LL. And once again, my mind went immediately to the impractical but enticing answer: forget internal combustion - I want an electric airplane.

Electrification would seem to be the magic bullet: very few moving parts, lower operating costs, quieter operation, consistent power at any altitude, no emissions, no carbon monoxide. Electric aviation has the potential to keep GA aircraft flying long after the last drop of 100LL is burned.

Before anyone jumps all of over me for being unrealistic - yes, we’re not there yet: energy density in batteries is still too low for XC ops; lithium ion batteries are prone to thermal runaway events and other dangers; the FAA is running decades behind the state of the art...

All that said, isn’t it still fun to think about? I for one hope to live long enough to enjoy a $25 hamburger while my RV-22 is parked outside, quickly charging.

So on to the thought experiment:

What would be required to eletrificate my RV-6A?

Assume for the sake of this game that the two wing tanks are replaced with power modules which can be replaced with better power modules as technology improves. For the sake of weight and balance, assume that the tanks remain at about 120 pounds / 54 Kg regardless of what’s in there: lithium ion batteries, hydrogen fuel cells, dilithum crystals, arc reactors, etc.

Is there a DC electric motor / controller system on the market that can produce the same 160 HP as my current IO-320 at (or preferably well below) the same cost?

If not, what would it take to produce a motor / controller system that generates 160 HP at 2700 RPM? Is this “rocket science” level stuff, or something that could be designed and built by a startup (or some dude in a garage)?

Do I need a full 160 HP, or will the lack of parasitic accessories (alternator, magneto, oil pump, fuel pump) allow me to operate with less?

If we rip out the old Lycosaurus and all its friends and replace it with a motor and controller setup that weighs 1/2 as much, how do we fix the W/B? More batteries up front? Extend the nose?

Do we need to provide cooling for the motor? For the motor controller? For the battery packs?

What other issues are there hiding in the weeds?
 
Electric

It is coming, no doubt. I follow some other sites related to this tech and recently I saw an electric motor that Yamaha has that is 150kw which is about 200 HP. The motors and controllers are available; it is the batteries that are still the limiting factor. CG issues can be dealt with; charging and cooling issues remain. Cost is a bit problematic at this point, unless you want to find a wrecked Tesla and and scavenge the batteries. Even then, you would need to create a custom pack from those used batteries and it would likely be relatively high voltage DC...accideny shorting it while in fabrication would be a sight to behold.

I think it is definitely possible for someone who wants to build, tinker, and push the envelope. Not so much for those who just want to fly...

Might be a retirement project for me!:rolleyes::D
 
rocketman1988 is 100% correct--the motors and drivers exist. That part of the equation has been thoroughly solved by the good folks in the automotive industry. The issue really comes down to energy storage, and batteries aren't there yet. And the same issues faced by EVs will apply just as much to aviation--speed of charge, range, cost, etc.

Unless/until battery technology progresses to the point where it has a similar energy density to fuel, I'd love to see someone come up with a fuel cell system for GA. Fast fill-up times, long range, better efficiency, less cooling drag, etc.
 
There is no rocket science here, it is all pretty easy and has been for a long time. Everything is better about an electric drive. The problem is, and always has been, energy storage. If you can find a battery cheap enough and light enough, it is a no brainer. And we are not yet even close to cheap enough and light enough for an airplane.

Tim
 
There is no rocket science here, it is all pretty easy and has been for a long time. Everything is better about an electric drive. The problem is, and always has been, energy storage. If you can find a battery cheap enough and light enough, it is a no brainer. And we are not yet even close to cheap enough and light enough for an airplane.

Tim
Today, you can (technically) get enough battery energy density to make very short flights in an RV with a 200hp motor, so we're only one major battery technology breakthrough away from fully electric flight. Thankfully lots of people are looking into this for applications much more lucrative than aviation.
 
Today, you can (technically) get enough battery energy density to make very short flights in an RV with a 200hp motor, so we're only one major battery technology breakthrough away from fully electric flight.

This statement has been true for about 25 years. But I’m sure it’ll happen any day now.
 
There are emissions

Electric vehicles produce carbon emissions but they do it remotely. Generating and transmitting the electricity to charge your electric vehicle is the reason. Solar and wind simply do no produce affordable power in sufficient quantities to be a viable source yet. Nuclear power generation can but with another set of issues.
 
Seems to me that if battery technology ever makes it practical, that it would be better to do it via a clean sheet design, or at least a major overhaul of the front end of whatever airframe you're using.

I had an A&P instructor decades ago that conceptualized a power plant in the fuselage driving props via hydraulic motors. His idea was that you could put the power plant (whether dyno-juice or electric) pretty much anywhere for w&b + aerodynamic reasons, and that hydraulic motors are so small for the available torque that you could do a familiar wing mounted prop twin with essentially no conventional engine nacelles.

A physically smaller electric motor would allow for a radically different cowl setup, so you could likely have an airplane thats much aerodynamically cleaner up front. Obviously at some point it has to get fat enough for a cockpit, but the pointy end could get much pointier, and you could likely get the same performance out of less h.p. because of the resulting drag improvements.

Interesting to think about, but since I'm 54, I honestly doubt if it will become anything other than a novelty in my remaining flying years. Some of the younger guys out here, sure, I hope you see it widespread and get your $25 hamburger.
 
This statement has been true for about 25 years. But I’m sure it’ll happen any day now.
Salty! and true. When I was a kid in the 70s we were sure we'd have flying cars before 1999. Not sure how they were supposed to be powered - I should have been paying more attention in school. :D

No doubt dead dinos are amazingly energy dense.

Look at the solar impulse - they kind of proved the concept of an electric aircraft - now it's up to the rest of us to take that work and run with it.

https://aroundtheworld.solarimpulse.com/

Some of the guys that built that are on this forum building RVs - I'm sure that they can chime in with their views.
 
My thought process

So by going electric, the battery just stores the energy. The electrons stored in the plane need to be generated somewhere. With batteries, the generation of the energy (electrons) is just moved to a bigger plant that is on the ground somewhere.

But Avgas creates the energy through a chemical process that also uses another chemical readily available, namely oxygen. So only half the constituents needed to create the energy for flight are carried aloft. Since rockets are in the same boat as electric airplanes, they are actually closer cousins in terms of efficiency than gas fueled airplanes.

So the green-ness of electric vehicles come from having the option of generating the electrons off site at various types of powerplants.

I find it interesting that an electric RV will always have the same landing weight as the takeoff weight. This eats into the range since the aircraft doesn't get lighter as it flies along.
 
Back to the thread ?

I've thought about this too. The motor isn't a problem, plenty of suitable motors. Also note that you get the same power regardless of altitude. So a lower power motor may be fine. You give up some in take off performance, but have unchanged performance at 10,000 and up.

Batteries - LiIon (ala Tesla) or LiFEPO4? LiIon has better energy per pound but more prone to run-away. One thought I had ... if the battery was at the CG point, could there be a quick release mechanism? If all safety items fail we can just drop the battery pack? :eek:

Due to the expense of batteries (currently I'm putting together some off grid packs) of just under $200 per kwh, the packs get really pricey fast. (that is about 1.3 HP for 1 hour) And as others mentioned, not light. That's why things like all-electric motor gliders are practical now. Little power needed due to low speed and hence low drag. The RV9 is likely a better candidate than the RV6. And a Kitfox probably better by far.

There are flexible solar panels... maybe put those on the wings and fuselage? Every bit helps.

I keep leaning back toward a series hybrid. On board engine & generator. But the problem we run into is while this works well for cars, it doesn't fit the model for aircraft. In a car the demand is very peaky with stops and starts. At times of low demand the engine/generator fills up the batteries. Then when you floor it at a green light you for a short time use max power.

An airplane profile (for most of us) is long duration of max cont. power. So then the genset needs to be sized as big as the original Lycoming... or it is just there to delay the exhausting of the battery.

In our use case, nothing prevents us from putting up a few cheap solar panels and using those to charge our hypothetical electric RV directly.
 
Fuel Cells?

Apparently we're at about 260 Watt-hours / kilogram (Wh/kg) for current lithium ion technology. Next-generation batteries may take that up to 400 Wh/kg. Things still in the lab (lithium-sulphur, lithium-air) can apparently get into the low 1000s range.

Hydrogen is 33,600 Wh/kg. Even with relatively inefficient fuel cells you get a whole lot more electrons out of a lot less mass.

There are a few production cars running on hydrogen fuel cells. (I actually saw a few when I was in California.) Anyone have any idea how much the fuel cells and storage tanks weigh? Are those capable of producing enough power to run a 120 kW motor?

(Yes, I also picture the Hindenburg - oh the humanity!)
 
Anyone have any idea how much the fuel cells and storage tanks weigh? Are those capable of producing enough power to run a 120 kW motor?

(Yes, I also picture the Hindenburg - oh the humanity!)

Sure you can produce enough power to run the motor, question is whether there is an airframe that can carry that weight.

Methinks the RV platform is not going to be the correct one for that use.

As was previously mentioned, battery pack on C/G for safety dump of the flaming mass----this would also allow for swapping a flat battery pack for a charged one. Now you need to create a network of battery exchange facilities at airports around the country. And, only one or two standard battery packs----think avgas or Jet A.


The lift distribution of a canard platform might be something to look at here.
 
I'm sure there's someone looking for investors for a all-electric self-piloting flying car project.

Get out your checkbook.
 
Battery technology will have to radically change/improve for this to be any thing more than an interesting science fair project. 100LL has over 100 times the power density of current lithium-ion batteries. When we get a step function change in battery tech, we will all be flying electric.
 
The year is 2029, Oshkosh Airventure has drawn 1000 EV aircraft. Imagine the lineups for the 50 recharge stations?

Reminds me of only a few years ago when there were a hand full of electrical outlets in all the camping areas and all those iphones to charge.
 
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Does anyone remember the CAFE/NASA Green Flight Challenge of 2011? It was won by the Pipestral Taurus G4. All electric, 4 passenger. As a comparison, the fuel weight of my RV is 32 gal x 6 lb/gal = 192 lb. This is 9% of the gross weight of 1750 lb. In contrast the battery weight of the Pipestral Taurus G4 was equal to the airframe weight and 30% of the gross weight (batteries ~500 kg, airframe less batteries ~500 kg, gross weight 1500 kg). Has battery technology developed substantially since 2011?

Nearly in my back yard, the electroBeaver flew over a year ago to great fanfare and media coverage. Only flown a few times since. I had heard the payload was one person (the pilot).

Excellent paper by the design team of the Pipestral Taurus G4
https://www.sv-jme.eu/article/pipis...eroplane-of-nasa-green-flight-challenge-2011/

Click on the black PDF button to download a copy.
 
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A few points to add

Just a few points on aspects people have mentioned:

Power is constant with altitude but thrust is not. As TAS increases for the same IAS, the thrust drops off. P=T*V Still, the performance drop-off is much less than IC.

Cooling big electric motors is a challenge. Cooling the motor controller is also a challenge. Cooling the battery is important too. There is less waste heat overall, but it is inconveniently located and the components can not tolerate high temps so you have to move the heat with less delta-T

The fact that batteries are charged from ground-based power generation offers something like 40% reduction in CO2. Much better energy conversion efficiency. This is why electric cars make sense.

Fuel cells can be very light. That’s not the problem. Remember Apollo used fuel cells to go to the moon, an application where weight is really at a premium. The issue is that they are very bulky. At NASA-Glenn they have both one-pass and regenerative fuel cells running with similar power. A 100 hp one-pass fuel cell is about the size of a VW Beetle. And it is not the fuel cell itself. It is a Miriad of pumps, valves, heat exchangers and plumbing.

I can’t prove this but my suspicion is that as battery energy density increases, the potential hazards increase too. Li-ion are already pretty dangerous. After working on an electric V-TOL for a couple of years At Zee.Aero I decided against an electric self-launch sailplane. The folks I worked with were top in the field and we had a couple of spectacular accidents. Boeing and Tesla have both had big mishaps and you can bet they really know what they are doing.
It is not a realm for amateurs. It is really easy to turn a $20,000 battery into hazmat.

In 1999 I led a NASA team to design a small electric airplane to fly on Mars. At that time the best batteries were Silver-Zinc at about 130 W-hr/Kg. They had Li-ion cells in the lab at 400 and that was going to be “right around the corner”. So here we are 22 years later and we are at 260. From my work at Zee this is just about the best you can do with Lithium. There will be gradual advance but nothing like what we need. It would take a new chemistry.
Just like fusion power, it will always be “right around the corner”.

One thing people often forget about is the 30-minute VFR reserve. The Zee test vehicle had 25 minute endurance so when we went to license it the FAA said we had -5 minute endurance. The loophole we used was to license it as a motor glider. The FAA was absolutely unyielding on the reserve. And for good reason. You can’t know your state of charge to any higher confidence than you can know your fuel remaining in a dinosaur powered airplane.
 
Motors

It is tough to get the power out of electric motors at the RPM we need. Out-runner motors run slower but still want to turn faster than we would like.

Gear boxes are heavy.

And cooling. Don’t forget cooling.
 
It is tough to get the power out of electric motors at the RPM we need. Out-runner motors run slower but still want to turn faster than we would like.

Gear boxes are heavy.

And cooling. Don’t forget cooling.

Gearboxes are heavy, but could be lighter when they don't need to be built to withstand the pulsing torque of a 4 cylinder aircraft engine.
 
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Gearboxes are heavy, but could be lighter when they don't need to be built to withstand the pulsing torque of a 4 cylinder aircraft engine.

That's probably true, but electric motors don't have a perfectly smooth torque delivery either and still have drivetrain harmonics. They are probably smoother than our 4 or 6 cylinder piston engines though.

Skylor
 
The electricity in my area is largely hydro-electric, nuclear with limited solar and bio-fuel (basically scraps from the forestry industry). All relatively "green" ways to produce energy.

Charge the plane and car batteries over night when everybody is asleep with the stoves, lights, saunas, air compressors and everything else is off. The water is flowing through the hydro-electric turbines regardless of load.
 
In 1999 I led a NASA team to design a small electric airplane to fly on Mars. At that time the best batteries were Silver-Zinc at about 130 W-hr/Kg. They had Li-ion cells in the lab at 400 and that was going to be “right around the corner”. So here we are 22 years later and we are at 260. From my work at Zee this is just about the best you can do with Lithium. There will be gradual advance but nothing like what we need. It would take a new chemistry.

Just like fusion power, it will always be “right around the corner”.
.

A very interesting post Steve. Like you, I doubt that there is any dramatic battery technology breakthrough right around the corner.

I am inclined to now believe that advances in battery technologies will be slow and incremental and that it will be a very long time before GA is broadly flying electric. There are mega dollars now being spent annually on global battery research but the nut is proving hard to crack and slow gains seem more likely than major breakthroughs.

Many people believe that the problem is simply a matter of energy density but there are many other crucial factors in producing a successful battery technology including, but not restricted to the following:

1. Suitability for low cost mass production.
2. Battery life.
3. Speed of recharge.
4. Intrinsic safety.
5. Secure availability of key elements/compounds in a political sense.

There are numerous new battery technologies in the pipeline that offer higher energy density than the current generation Li-ion. But they just don’t tick all the other boxes.
 
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An airplane profile (for most of us) is long duration of max cont. power.
Long duration of continuous power, yes, but not maximum. Who cruises at full throttle? If you do, there's at least one other way to be more efficient in the air... :)
 
Cooling big electric motors is a challenge. Cooling the motor controller is also a challenge. Cooling the battery is important too. There is less waste heat overall, but it is inconveniently located and the components can not tolerate high temps so you have to move the heat with less delta-T
At RV-speeds we have a lot of cooling air handy. Well designed, a cooling plenum could even offset the cooling drag... Like on the P-51.
 
Long duration of continuous power, yes, but not maximum. Who cruises at full throttle? If you do, there's at least one other way to be more efficient in the air... :)

Who does? I do.

I'm out west, and clearing the mountains to go anywhere significant means I'm at 10,000'. At 8000' DA I'm at 75% power. Now, since I'm in the SW, a standard temp day is rare. On my last long XC I was up at 12,500 (trying to stay above thermals), with a DA of 16,000.

Now, if I still lived in Minn, the situation would be different....
 
Long duration of continuous power, yes, but not maximum. Who cruises at full throttle? If you do, there's at least one other way to be more efficient in the air... :)

From takeoff threshold until top of descent, nearly every flight for me.

I didn't build a fast plane to fly it slow.

Only reason to pull it back is heavy turbulence or trying to stretch range - and I installed additional fuel tankage so I don't have to stretch range.
 
Electric vehicles produce carbon emissions but they do it remotely. Generating and transmitting the electricity to charge your electric vehicle is the reason. Solar and wind simply do no produce affordable power in sufficient quantities to be a viable source yet. Nuclear power generation can but with another set of issues.

Yeah, so I have to disagree with you on this one. This is simply not true. I grew up on a farm where all of our power was generated by wind. And later by solar as well. In the 70's and 80's. This was for powering anything from the lights, to the drill, to the welder etc. Of course there was a battery bank and inverter too. But the principle remains.

What you're saying is actually just some company that wants to put a spin onto something because they have some commercial reason to do so. Nowadays there are entire countries that, for some days of the year, run their entire grid off of solar or wind. Oh and solar and wind are cheaper than just about anything else out there even taking capital expenditure into account. Of course you have to have some sort of storage bank in the grid to store excess capacity (when there's too much wind) and release it again when there's too little. Goes without saying. If you have an interconnected, efficient national grid (like any modern nation should have), this is easily and economically achieved through hydro electrical storage dams.
 
There are numerous new battery technologies in the pipeline that offer higher energy density than the current generation Li-ion. But they just don’t tick all the other boxes.
Maybe not with traditional batteries that we generally think about but have you heard of fuel cells...? Both hydrogen fuel and methanol fuel cells... The methanol fuels cell especially is an interesting development. Very high energy density, you fill it up like a normal gas tank, it converts the methanol straight into electricity, a little bit of CO2 emissions but nothing major, no issues with "battery life", Intrinsically safe (well at least as safe as flying around with Avgas in your tanks), and widely available. Couple this with an electric motor with only 4 moving parts, with an energy conversion efficiency of 97% vs. a Lycoming's 30% and it makes for an interesting solution. The technology hasn't been scaled yet, but watch this space.
 
you fill it up like a normal gas tank, it converts the methanol straight into electricity,

Isnt methanol corrosive to alum?

What capacity is there to manufacture it, what is the capacity to distribute it.

Storage issues?
 
Yeah, so I have to disagree with you on this one. This is simply not true. I grew up on a farm where all of our power was generated by wind. And later by solar as well. In the 70's and 80's. This was for powering anything from the lights, to the drill, to the welder etc. Of course there was a battery bank and inverter too. But the principle remains.

What you're saying is actually just some company that wants to put a spin onto something because they have some commercial reason to do so. Nowadays there are entire countries that, for some days of the year, run their entire grid off of solar or wind. Oh and solar and wind are cheaper than just about anything else out there even taking capital expenditure into account. Of course you have to have some sort of storage bank in the grid to store excess capacity (when there's too much wind) and release it again when there's too little. Goes without saying. If you have an interconnected, efficient national grid (like any modern nation should have), this is easily and economically achieved through hydro electrical storage dams.

A significant portion of the electricity of Canada and US Eastern seaboard comes from hydroelectric dams. A good chunk of it is nuclear too.
 
Isnt methanol corrosive to alum?

The chemical methanol itself - no.

The method used to produce it, where the product is acidic, yes. That's what started the old wives tales about ethanol being corrosive to aluminum decades ago. It's not - when pure - but the old (no longer used) production methods frequently turned out an acidic product, which WAS corrosive to aluminum. Same applies here to methanol.
 
Don’t hold your breath.

Maybe not with traditional batteries that we generally think about but have you heard of fuel cells...? Both hydrogen fuel and methanol fuel cells... The methanol fuels cell especially is an interesting development. Very high energy density, you fill it up like a normal gas tank, it converts the methanol straight into electricity, a little bit of CO2 emissions but nothing major, no issues with "battery life", Intrinsically safe (well at least as safe as flying around with Avgas in your tanks), and widely available. Couple this with an electric motor with only 4 moving parts, with an energy conversion efficiency of 97% vs. a Lycoming's 30% and it makes for an interesting solution. The technology hasn't been scaled yet, but watch this space.

Fuel cells are in fact a very old technology. The first hydrogen fuel cells to be used commercially were in the 1960s during the NASA Gemini program. Methanol fuel cells date back to the 1990s. Both technologies have intrinsic limitations which have proven difficult to overcome despite huge amounts of research over a long period of time. In the year 2012 alone the US granted almost 1000 patents on fuel cell developments. Don’t hold your breath waiting for the big breakthrough on fuel cells.
 
Fuel cells are in fact a very old technology. The first hydrogen fuel cells to be used commercially were in the 1960s during the NASA Gemini program. Methanol fuel cells date back to the 1990s. Both technologies have intrinsic limitations which have proven difficult to overcome despite huge amounts of research over a long period of time. In the year 2012 alone the US granted almost 1000 patents on fuel cell developments. Don’t hold your breath waiting for the big breakthrough on fuel cells.

Here you go - https://www.carscoops.com/2020/03/536-hp-gumpert-nathalie-first-edition-methanol-fuel-cell-sports-car-costs-455000/ An electric German sports car with a range of 820kms on a full 65 liter Methanol tank. I'm not saying that this can be implemented exactly like it is into a light plane and I'm also not saying that it will happen in the next 5 years, but it does show proof of concept.
 
Here you go - https://www.carscoops.com/2020/03/536-hp-gumpert-nathalie-first-edition-methanol-fuel-cell-sports-car-costs-455000/ An electric German sports car with a range of 820kms on a full 65 liter Methanol tank. I'm not saying that this can be implemented exactly like it is into a light plane and I'm also not saying that it will happen in the next 5 years, but it does show proof of concept.

You got me all excited, but it looks like the fuel cell in that car is only 15kW/20HP, with a big battery bank. It's a step in the right direction, though.

Both technologies have intrinsic limitations which have proven difficult to overcome despite huge amounts of research over a long period of time. In the year 2012 alone the US granted almost 1000 patents on fuel cell developments. Don’t hold your breath waiting for the big breakthrough on fuel cells.
What limitations are you referring to?
 
What limitations are you referring to?

The car in question, the Gumpert Nathalie, uses a Reformed Methanol Fuel Cell which means that it reforms methanol into hydrogen. After that it’s essentially a hydrogen fuel cell. That means that unlike a pure hydrogen fuel cell CO2 green house gas emissions are produced in the reforming process. This technology is also both expensive and complex. The Gumpert Nathalie is a boutique 2 seat sports car for millionaires. It weighs 1800 kg and costs $460,000. I doubt that this is a preview of the technological future for cars and the mainstream car manufacturers all agree because they’re headed either towards pure hydrogen fuel cells or battery power (with most embracing the latter).

Methanol fuel cells may have a future in long distance heavy transport but it is doubtful they will play any role in mainstream automobiles or GA aviation.

This issue is in fact very complex and I recommend VansAirforce readers who are interested in the topic to do some research through Google and Wikipedia.
 
Yeah, so I have to disagree with you on this one. This is simply not true. I grew up on a farm where all of our power was generated by wind. And later by solar as well. In the 70's and 80's. This was for powering anything from the lights, to the drill, to the welder etc. Of course there was a battery bank and inverter too. But the principle remains.

The problem here is that this is one anecdotal example. The reality is that wind and solar power generation in all but the most extreme examples, are not efficient. The cost to manufacture and install the infrastructure is not typically realized before repair and replacement cycle is complete. Can you do it? Of course! Is it cost effective when an alternative exists? Not even close! Many people use these technologies because there is no alternative, they like being off the grid, or they believe them to be green. 10 minutes of real research will prove out that the technology is a money maker for everyone but the end user. The only exception is when subsidized - and then only when at 40+%. But then, who pays the subsidies? The taxpayer - so now we are back to square one.

Now take that same technology that is expensive and inefficient and apply it to aircraft where value and/or efficiency is critical and you quickly see that there is no foreseeable time when this becomes mainstream. There is simply nothing that can store energy like hydrocarbons.
 
According to the Tesla website, the battery pack in the 85 kWh version of their cars weighs 1200 pounds.

The OP in this thread cited a 200 hp / 150 kWh engine as the goal.

That 1200 pound battery pack would deliver less than an hour of power, at moderate throttle settings.

If you could more efficiently engineer the battery pack, since weight matters more in airplanes than cost, maybe you could cut 100 pounds out of that.

Even at a 10% improvement per year in weight or energy density, we are a long way from XC flight on a battery pack.

United Airlines announced yesterday some urban air transport vehicle plans for 2025, but it was pretty short haul. The stuff Uber has been hyping is short haul, too. Lots of start-ups are talking a big game about short air travel in what are basically giant drones by 2025 or 2030. Given how this technology advances and the FAA approval process actually works, I figure adding 5 or 10 years to any of these targets feels about right. There is no way we will be watching people fly over us on the highway 4 years from now in four seater quadrocopters.

When my engine gets to 2,000 hours and overhaul, I would absolutely love to tear out everything messy and carbon emitting and replace it with silicone, lithium, and copper. Thank goodness that means I'm probably revisiting my powerplant in 2040 or later.
 
The reality is that wind and solar power generation in all but the most extreme examples, are not efficient. The cost to manufacture and install the infrastructure is not typically realized before repair and replacement cycle is complete. Can you do it? Of course! Is it cost effective when an alternative exists? Not even close! Many people use these technologies because there is no alternative, they like being off the grid, or they believe them to be green. 10 minutes of real research will prove out that the technology is a money maker for everyone but the end user. The only exception is when subsidized - and then only when at 40+%. But then, who pays the subsidies?

Exactly!!!

I toured the Tesla Gigafactory a couple years ago, and when we got ot the solar panel stuff, I asked the question point blank about the electricity used to manufacture all components vs. the output of a solar panel, the guide admitted it was still a negative for the projected life of the panel.

I have watched the cycle of government subsidy caused solar electric boom, to the withdrawal of the subsidy and the resulting decline of sales/crash occur 3 times since the 1960s.
 
Exactly!!!

I toured the Tesla Gigafactory a couple years ago, and when we got ot the solar panel stuff, I asked the question point blank about the electricity used to manufacture all components vs. the output of a solar panel, the guide admitted it was still a negative for the projected life of the panel.
.

Is that actually correct? That is surprising to hear. I have a 5KWh rooftop system installed on my house that went active in April 2009. To date, the system has generated 63.7 mWh of energy. Manufacturing takes more than 1200 Wh per watt of generation capability? And I'm only around halfway through the 25 year expected life of the panels.
 
I have a 5KWh rooftop system installed on my house that went active in April 2009. To date, the system has generated 63.7 mWh of energy.

My previous home had a 6.9 KW system on the hangar roof, cost 43k$ after the gov tax credit. We had an all electric place, other than propane for the heating. I only installed enough PV to take out the top tiers of the electricity usage and due to the rate structure that was the most effective way to do it at that time.

I also replaced the old 80% propane furnace with a new 96% heat pump. Propane was horridly expensive 600/month during the cold. Also, LET lighting and other electricity saving efforts.

It cost me about 250/month for the PV system purchase. But I saved money overall due to shifting the heating load to the lower cost electricity vs propane.

This was all motivated by the fact I could save $$$ overall.

Now, back to the cost/output of PV panels.

Consider the total electricity used to smelt the bauxite and the various steps to get a final alum alloy.

Consider the total electricity used to manufacture the glass from raw materials.

Consider the total electricity used to refine the silicon for the cells themselves.

Ditto for other components of the panel.

As I said, as of a couple years ago, the Tesla guy said the total electric load to make the panels was more than the projected generation over the projected life of the panel. This has improved over the last 50 or so years that I have been looking at PV, but still a net minus AFAIK.
 
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I have panels, thank you tax payers. It made sense with the 33% credit, they should pay for themselves in 15 years. Expected life/warranty is 25 years. So all that being said, without the incentive they are just barely paying for themselves. Not to mention the initial capital required. My power company does a 1 for 1 kwh transfer so I don't need batteries. If I needed storage they probably would not have paid for themselves even with the credit. Those needing a tax credit can afford them, this is a very small percentage of income earners. This also means we need to be in the house 20 years. It works on a small scale with a limited power demand; I think the economics of it starts to skew the other direction with commercial applications and larger power consumption as the amount on infrastructure and panels required will obviously increase. Solar can't replace oil/gas, but can supplement. Even those countries that run their grid on solar/wind for a few days a year; what about the rest of the year? Electric GA airplanes that have similar performance specifications to today's is a whole different animal; I don't think we'll see them on a large scale in most of our lifetimes.
 
I toured the Tesla Gigafactory a couple years ago, and when we got ot the solar panel stuff, I asked the question point blank about the electricity used to manufacture all components vs. the output of a solar panel, the guide admitted it was still a negative for the projected life of the panel.

Hang on a minute....let’s get this right....you’re saying that you got your information from “the tour guide” at a Tesla factory. Well, considering that your source is just a tour guide, and considering that Tesla has always outsourced their solar panels to numerous third parties including Panasonic and more recently Hanwha, I would say your source of information is very dubious indeed. Call me sceptical but you’ll need to provide more robust evidence to support your premise that it takes more electricity to manufacture a modern solar panel than the panel can ever generate over its entire functioning life.

The problem now with this thread is that it is tending to morph from a discussion on electric powered aircraft to a more general political discussion on the merits of fossil fueled grid power compared to renewables. In terms of the latter people often believe what they want to believe and cherry pick the information that supports their politics (however flimsy that information might be).
 
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... and to add to the discussion, here's one more point:
Recycling!

Are the components, batteries et al, used in your future e-RV recyclable, yes/no, at what cost, at what energy?

Illusions, more illusions :(
 
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