Why electric planes are inevitable

[David Megginson]

By comparison, my conventional 2013 Mazda 3 Sport (6-speed manual transmission) averages around 6.5 litres/100 km on the highway, or about 36 mpg. With a 50 litre / 13 gallon tank, we fill it up rarely enough — maybe 2x/month when we're not taking a trip somewhere — that it's not worth looking for a station with cheaper gas.

 

[Palmpilot]

I forgot to mention that mine is a five-speed manual transmission.

 

[FastEddieB]

Hybrids do not work well on the highway unless there are hills. There is some advantage with hills if they are large enough as you can reclaim some energy going back down.

I think physics tells us hills will always be a net negative. You never quite earn back the extra energy used to climb the hill.

 

[Salty]

I think physics tells us hills will always be a net negative. You never quite earn back the extra energy used to climb the hill.

True, but without the batteries you are getting zero back, with batteries you do get some back.

 

[FastEddieB]

Do hybrid cars use full alternative ICE powertrains, or just a fuel-powered generator to top up or supplement the battery?

Can’t speak for all hybrids, but ours has a smallish 1.5L Atkinson Cycle engine. Most times it’s not driving the wheels directly, which can make it feel sort of disconnected. But combined with the battery, the car has plenty of oomph.

 

[tspear]

Do hybrid cars use full alternative ICE powertrains, or just a fuel-powered generator to top up or supplement the battery?

The Chevy Volt G1, is the only mas produced range extender car I am aware of. As in, no mechanical connection between the ICE and the wheels.
Most other hybrids have the ICE transmission mechanically linked to the wheels, with a second electric motor also connected to the transmission.
There is a clutch between each engine and the transmission which allows the engine to disengage or lock. This is done for efficiency. Converting mechanical energy to electric and back again has a significant penalty compared to the weight of the complex transmission.
(Note: when charging some companies have the electric motor act as a generator, others use a dedicated generator. Size of the motors involved, total power demands and many other considerations play into how this is designed).

Tim

 

[Palmpilot]

I think physics tells us hills will always be a net negative. You never quite earn back the extra energy used to climb the hill.

When I drove a box truck full of my belongings from coast to coast, I noticed that I got better mileage in the mountains than on flat land. I came to the conclusion that less energy was lost to drag on the upgrades due to the slow speed, and the drag on the downgrades didn't matter because most or all of the propulsion force was coming from gravity.

 

[Palmpilot]

True, but without the batteries you are getting zero back, with batteries you do get some back.

I think gravity is an excellent energy-storage medium.

 

[Salty]

I think gravity is an excellent energy-storage medium.

This would be an argument against hybrids.

 

[Palmpilot]

The Chevy Volt G1, is the only mas produced range extender car I am aware of. As in, no mechanical connection between the ICE and the wheels.
Most other hybrids have the ICE transmission mechanically linked to the wheels, with a second electric motor also connected to the transmission.
There is a clutch between each engine and the transmission which allows the engine to disengage or lock. This is done for efficiency. Converting mechanical energy to electric and back again has a significant penalty compared to the weight of the complex transmission.
(Note: when charging some companies have the electric motor act as a generator, others use a dedicated generator. Size of the motors involved, total power demands and many other considerations play into how this is designed).

Tim

On my Civic, the gasoline engine is connected to the wheels through a normal drive train, except that the motor/generator is inline between the engine and the clutch.

In order to get the most out of the regenerative braking, I had to train myself to leave the clutch engaged throughout most of the deceleration.

I don't know whether Honda is still doing it that way or not.

 

[A Martin]

.

Elaine debuts the Mercedes AA electric

https://www.powerlineblog.com/ed-assets/2021/09/Mercedes-Electric-Car.mp4?_=1

.

 

[Palmpilot]

This would be an argument against hybrids.

Well, it is true that trying to go fast on a long upgrade is a losing proposition in mine. The battery ends up being fully charged at the bottom of a long downgrade, however.

 

[genna]

The Chevy Volt G1, is the only mas produced range extender car I am aware of. As in, no mechanical connection between the ICE and the wheels.
Most other hybrids have the ICE transmission mechanically linked to the wheels, with a second electric motor also connected to the transmission.
There is a clutch between each engine and the transmission which allows the engine to disengage or lock. This is done for efficiency. Converting mechanical energy to electric and back again has a significant penalty compared to the weight of the complex transmission.
(Note: when charging some companies have the electric motor act as a generator, others use a dedicated generator. Size of the motors involved, total power demands and many other considerations play into how this is designed).

Tim

i3, i8, Fisker(Karma now). Although the last two are hardly mass produced

 

[Morgan3820]

I agree that maintenance costs exist, but especially for solar it's more of a fixed cost and not related to whether the solar panel is producing energy or not.

And while there are projects that have failed, the vast majority have found profitability. Every industry has projects that fail or one reason or another. Wind is particularly mature reaching cost parity with gas and coal. There's still work to be done with solar. There's no one size fits all solution. Solar makes a lot of sense in the southwest, but less so in Minnesota. Intermittency is indeed a problem, but is an area of active research and effort. A world where 100% of energy coming from wind and solar will never exist, but I trust in human ingenuity to find a sustainable solution.

Around here, we have converted a lot of productive cropland to solar farms as a result of some progressive state legislation. But hey, who needs to eat.

 

[Albany Tom]

Well, we've outsourced most manufacturing and a lot of energy, why not give up on food exports, too. We can see how being a "service economy" plays out in the world market, renting poorly written software and animated movies.

Too political?

 

[FastEddieB]

On my Civic, the gasoline engine is connected to the wheels through a normal drive train, except that the motor/generator is inline between the engine and the clutch…

I don't know whether Honda is still doing it that way or not.

How Honda handles* it in the Clarity:

Looks complicated, but pretty seamless and transparent in practice.


*Or should I say “handled”. Clarity production has ceased.

 

[Mahneuvers]

Regarding city vs highway hybrid performance, one aspect I have not read yet regards when hybrids run on all electric. For my Camry, that speed is 40 MPH. Above 40 and the engine runs regardless if the power is needed. If there's no one behind me on a 45 MPH road and I have time, I keep the car at 40 MPH. On flat or descending roads I can quickly get the trip MPG over 40 by doing so.

 

[wayne]

True, but without the batteries you are getting zero back, with batteries you do get some back.

Gravity. I can tell you from the instant mpg gauges that you get far better mpg going downhill, which makes up, somewhat, for the worse mpg going uphill.

This would be an argument against hybrids.

Why? Hybrids are really about not having a big engine to get good acceleration. A car doesn't need much HP to cruise on the highway, but it needs quite a bit to accelerate quickly. By building a smaller engine tuned for a lower output and you can better mpg. Then the electric boost is there for accelerations and steep climbing.

 

[Bob Noel]

Regarding city vs highway hybrid performance, one aspect I have not read yet regards when hybrids run on all electric. For my Camry, that speed is 40 MPH. Above 40 and the engine runs regardless if the power is needed. If there's no one behind me on a 45 MPH road and I have time, I keep the car at 40 MPH. On flat or descending roads I can quickly get the trip MPG over 40 by doing so.

My old hybrid (2005) would have the engine always running above 40 mph

My current hybrid will have the engine due to drive power. Sometimes on the highway it'll run on electric. It's much more aggressive about using battery.

 

[pfarber]

No he didn't.

Snopes is a joke.

If you said you created X, you don't have to invent every underlying part.

i can create a sand castle, but i didnt invent the sand

 

[Doug Reid]

Just food for thought here..in 1984 I purchased an Oldsmobile Cutlass special edition with a diesel engine..a full size car that got 30-35 mpg all day long. Not bad for a nice family sized vehicle...not a tiny spam can. That was 37 years ago.

 

[Mahneuvers]

...It's much more aggressive about using battery...

My Camery is a 2007 w/ 140K miles so probably the same tech as your 2005. A concern at the time I bought it was how long before I had to replace the batteries. So far the batteries are running strong. I read years ago Toyota expects batteries to last as long as the vehicle itself partly due to shallow discharging. I'm wondering if battery life will be negatively impacted with more aggressive discharge.

 

[Velocity173]

The Chevy Volt G1, is the only mas produced range extender car I am aware of. As in, no mechanical connection between the ICE and the wheels.
Most other hybrids have the ICE transmission mechanically linked to the wheels, with a second electric motor also connected to the transmission.
There is a clutch between each engine and the transmission which allows the engine to disengage or lock. This is done for efficiency. Converting mechanical energy to electric and back again has a significant penalty compared to the weight of the complex transmission.
(Note: when charging some companies have the electric motor act as a generator, others use a dedicated generator. Size of the motors involved, total power demands and many other considerations play into how this is designed).

Tim

The Volt’s ICE actually does have a mechanical connection to the transmission. In mode 4 (dual motor extended range) driving above approximately 30 mph, the ICE can engage the transmission to assist in propulsion.

In my experience with owning the Volt and the Ford Cmax, the little 84 hp Volt operating in hybrid mode gets only 38 mpg. The Cmax 141 hp Atkinson Cycle hybrid got about 42 mpg. My Volt is a PHEV so overall I got better MPG than the Cmax. Currently I think I’m at 180 MPG lifetime.

 

[tspear]

The Volt’s ICE actually does have a mechanical connection to the transmission. In mode 4 (dual motor extended range) driving above approximately 30 mph, the ICE can engage the transmission to assist in propulsion.

In my experience with owning the Volt and the Ford Cmax, the little 84 hp Volt operating in hybrid mode gets only 38 mpg. The Cmax 141 hp Atkinson Cycle hybrid got about 42 mpg. My Volt is a PHEV so overall I got better MPG than the Cmax. Currently I think I’m at 180 MPG lifetime.

That is the Gen 2 Volt. The range extender version, Gen 1, I believe was a rush implementation to get something out the door. And a range extender is much easier to develop and build.
However, for most people it will end up being less efficient.

Tim

 

[Bob Noel]

I'm wondering if battery life will be negatively impacted with more aggressive discharge.

I'm guessing that one reason my current (no pun) hybrid is more agressive about using battery is because it has a larger battery capacity (iirc).

 

[Palmpilot]

Regarding city vs highway hybrid performance, one aspect I have not read yet regards when hybrids run on all electric. For my Camry, that speed is 40 MPH. Above 40 and the engine runs regardless if the power is needed. If there's no one behind me on a 45 MPH road and I have time, I keep the car at 40 MPH. On flat or descending roads I can quickly get the trip MPG over 40 by doing so.

My Civic hybrid never runs on all electric. That's one of the differences between it and a Prius. The electric motor/generator only adds to the gas engine's output
during acceleration or on upgrades. I think that's why its gas mileage is better on the highway than on city streets. (As I mentioned before, I don't know if Honda is still doing it that way.)

 

[Palmpilot]

Snopes is a joke.

I disagree.

If you said you created X, you don't have to invent every underlying part.

i can create a sand castle, but i didnt invent the sand

See Post #66. "Create" has a broader range of meanings than "invent." Depending on the context and what you created, you may not have had to invent ANYTHING.

 

[Velocity173]

That is the Gen 2 Volt. The range extender version, Gen 1, I believe was a rush implementation to get something out the door. And a range extender is much easier to develop and build.
However, for most people it will end up being less efficient.

Tim

No, the Gen 1 has it as well. Gen 2 is slightly different in the conditions when ICE engages the trans. Originally Gen 1 wasn’t supposed to have that capability but they re-engineered it at the last minute for improved efficiency.

https://cars.usnews.com/cars-trucks/chevrolet/volt/2011/performance

 

[genna]

Just food for thought here..in 1984 I purchased an Oldsmobile Cutlass special edition with a diesel engine..a full size car that got 30-35 mpg all day long. Not bad for a nice family sized vehicle...not a tiny spam can. That was 37 years ago.

That car was also near 1000lb lighter than a modern midsize. That is a big difference. And probably pretty gutless. Modern diesel will do that while being a lot heavier, safer, more comfortable and have a lot more performance and reliability

Edit. Gas version was close to 1000 lighter, diesel was about 5-600 lighter(3417lb curb). Still a pretty big difference. And it had 85hp/165lb-ft... weak.

 

[tspear]

No, the Gen 1 has it as well. Gen 2 is slightly different in the conditions when ICE engages the trans. Originally Gen 1 wasn’t supposed to have that capability but they re-engineered it at the last minute for improved efficiency.

https://cars.usnews.com/cars-trucks/chevrolet/volt/2011/performance

View attachment 100467

Interesting, I never researched, but I posted what I have read multiple times on the net.

Tim

 

[Tantalum]

I had to train myself to leave the clutch engaged throughout most of the deceleration

You have a manual hybrid? If yes; cool.. and B, I didn't know that existed. Otherwise, if it's automatic, how did you train yourself? I have some experience in hybrids (Nissan) and they would coast when the foot was off the gas, and even just barely resting my foot on the brake would spool up the regen before the actual mechanical brakes engaged

 

[Firepac]

Pffft. I'm waiting for nuclear powered planes.

 

[Palmpilot]

You have a manual hybrid? If yes; cool.. and B, I didn't know that existed. Otherwise, if it's automatic, how did you train yourself? I have some experience in hybrids (Nissan) and they would coast when the foot was off the gas, and even just barely resting my foot on the brake would spool up the regen before the actual mechanical brakes engaged

Yes, it's a manual five speed. I don't know how to control the clutch on an automatic transmission, or whether they even have clutches.

My car is a 2003. I don't know whether they still make the manual version.

 

[Mtns2Skies]

Around here, we have converted a lot of productive cropland to solar farms as a result of some progressive state legislation. But hey, who needs to eat.

A vast majority of US cropland is not for food production, but rather the heavily subsidized corn industry for ethanol to be used in fuel. That whole process ends up producing more carbon than it otherwise would straight from gasoline which is just asinine.

So if we converted all of the farmland dedicated to ethanol production to solar farms we would net a huge energy boost for the country, in my mind your comment isnt really a loss.

 

[Palmpilot]

A vast majority of US cropland is not for food production, but rather the heavily subsidized corn industry for ethanol to be used in fuel. That whole process ends up producing more carbon than it otherwise would straight from gasoline which is just asinine.

So if we converted all of the farmland dedicated to ethanol production to solar farms we would net a huge energy boost for the country, in my mind your comment isnt really a loss.

I don't have an opinion on whether ethanol in fuel is a good thing or a bad thing, but isn't the the carbon released from it equal to the carbon removed from the air when the crop is grown?

 

[Mtns2Skies]

I don't have an opinion on whether ethanol in fuel is a good thing or a bad thing, but isn't the the carbon released from it equal to the carbon removed from the air when the crop is grown?

With my vast and extensive research... On YouTube.... Not really.

 

[FastEddieB]

Pffft. I'm waiting for nuclear powered planes.

They toyed with the idea in 1954. The towers are still up in Oak Ridge, not far from our TN home.

https://www.ornl.gov/blog/ornl-reporter/lofty-ambitions

 

[bflynn]

Pffft. I'm waiting for nuclear powered planes.

Well, NASA is working on a reactor called KiloPower, which is 1-10 kw and light enough to be lifted to orbit. Maybe that's your candidate, the first experimental to be certified by the FAA and the NRC.

 

[tspear]

@Mtns2Skies

Your posts conflict with each other. First you state the vast majority of US cropland is is dedicated to biofuels. They post a link which states the number is 8.8% of corn farmland is for ethanol.

The video also has many fundamental errors, starting with negative kcal calculation. The announcer has the implied assumption that the only energy source is photosynthesis.
There are many other issues.

With all that said, biofuels meet a need that batteries do not. Energy density. It will take a number of years for biofuels to become really cost effective, however they have continued to decline in price at the same time produce less total carbon emissions than fossil fuels.
He also missed a couple key points, due to climate the US generally does not grow sugar cane, we grow sugar beets for the most part. The reason sugar beets are not converted to alcohol is the candy industry has managed to block sugar being used for alcohol in vehicles, because sugar beet farmers have managed to lobby for and keep an import restriction on sugar (dates back to the early 1900s if my memory of history class is correct). Sugar is one of the few mantional resources which automatically gets regulated in a time of war, and is considered a national security issue of all things.

Tim

 

[GaryM]

@Mtns2Skies

He also missed a couple key points, due to climate the US generally does not grow sugar cane, we grow sugar beets for the most part. The reason sugar beets are not converted to alcohol is the candy industry has managed to block sugar being used for alcohol in vehicles, because sugar beet farmers have managed to lobby for and keep an import restriction on sugar (dates back to the early 1900s if my memory of history class is correct). Sugar is one of the few mantional resources which automatically gets regulated in a time of war, and is considered a national security issue of all things.

Tim

Sugar beets, and we grew a lot of them when I was still out on the family farm, contain a remarkably low concentration of sugar. Taste a chunk, if you get the opportunity. Hardly any trace of sweetness.
What sugar beets are really good at is generating biomass, huge tonnage of beets from an acre of land. Getting the sugar out takes an enormous amount of energy; it only works economically because beet growing regions tend to also have cheap hydropower available. But it would be an expensive way to make alcohol for fuel.