It's funny how we have to wait for real and serious competition before we can get nice things. It took AMD, then Apple, to trounce Intel before we finally started seeing Intel take things seriously, and only now that the electric car trend is really taking off do we start to see real innovations in internal combustion engines.
I have a 1981 Diesel Chevette which can get 50 miles to the gallon when driven at a steady highway speed. If that forty year old fully iron engine can get 50 miles to the gallon in a car that's as aerodynamic as a brick, then why aren't new cars getting 80 miles to the gallon? Is our technology really that shitty? Or is it that the carmakers have marketed performance and "sportiness" to us over efficiency?
They certainly don't want to make engines that can last forty years and 750,000 miles, but that's another issue.
So the real question is this: if we can have 80, 100, 150, perhaps even 200 mile-per-gallon combustion engines, and if we can grow biodiesel from algae and even produce it using processes which pull CO2 from the air, then how much energy and carbon output could we save by not building limited life batteries and by not suffering the waste of electricity transmission and storage?
It's not all one thing or the other, and it never should be, but we've been milking the old internal combustion cash cow for so long we've virtually guaranteed her death, even though evolution of the internal combustion engine would be a net benefit.
I have a hobby car that is similar; I can get right around 40MPG on the highway and it makes more power than a stock modern version of itself. The real reason the newer cars don't get better mileage is a few factors:
Old cars do well steady state, but are far less efficient in transient states; modern engines are far better at that.
Old cars have absolutely toxic emissions. I mean literal 100's of times worse than modern engines (especially diesels), which are already terrible.
Couple these two major factors and you'll see where most of the advances have gone. That said, I don't think you are completely incorrect either; incentives have to be put into the right places to drive these innovations forward.
If you want to see state of the art efficiency for fossil fuel engines look at trains. They are more heavily regulated for emissions than bunker fuel ships, and the amount of fuel per ton-mile used is tiny compared to a personal vehicle due to a few factors (load vs vehicle weight, efficiency of acceleration/deceleration, engines operating only at peak power/efficiency and the traction motors being electric, etc.).
On a side note, the lack of parts to keep an old car in compliance with emissions is driving me insane. My hobby car is a HUGELY popular car from 20-30 years ago and the supply of parts to keep it on the road is drying up already. Due to it's factory state of tune (naturally aspirated, ~100hp/liter) aftermarket discount parts are not suitable and fail quickly, sometimes damaging other parts. OEM parts are so rare now that they are getting painfully expensive to continue procuring them, and for emissions related systems the only quality parts left are the high end aftermarket (which aren't legal). It's becoming almost impossible to keep these vehicles legal, which I'm sure is intended. I'm at the point where I'll likely run the "illegal" (though perfectly identical if used properly) parts for 23 out of the 24 months it's on the road, and only use the almost impossible to obtain OEM parts for the 1 month needed to get it sorted for emissions testing.
There's not much point to a 750,000 mile engine, as the rest of the car is worn out and rusted out at 200,000 miles.
> if we can have 80, 100, 150, perhaps even 200 mile-per-gallon combustion engines
Well, we can't.
Internal combustion engines have steadily gotten better, not stagnated.
In the 1970s, I heard all about oil companies buying 200 mpg carburetors to keep them off the market. My dad laughed at that, saying the military would never let patent law keep them from making 200 mpg tanks and stuff. Gas is a gigantic logistical problem for a mechanized military.
>> There's not much point to a 750,000 mile engine, as the rest of the car is worn out and rusted out at 200,000 miles.
I've seen plenty cars get 300,000 miles here in Texas without a spot of rust on them. Do you live in Michigan or something? The salty states have only known rust and salt lol
> In the 1970s, I heard all about oil companies buying 200 mpg carburetors to keep them off the market. My dad laughed at that, saying the military would never let patent law keep them from making 200 mpg tanks and stuff.
I know nothing about that story, but the military is budgeted by Congress and commanded by the President, and thus subject to political influence. Plenty of the what the military does is inefficient economically and militarily.
Cummins and Achates Power was supposed to have delivered two working prototype engines to the US Army's TARDEC to be installed into a Bradley for evaluations in 2019. I'm assuming that they testing went well enough to prove that the engines are viable enough for further development.
Uncertain if the technology will ever meander it's way to regular car market, but interesting to see ICE development continue on.
You being seriously injured or dying in an offset ~30mph collision, versus getting out of the car dazed and confused is the difference. And yes, passenger safety didn't change much for American cars between the 50's and early 80's.
You causing more pollution (particulate, NOx, etc) than a hundred luxury SUVs or more, is the difference.
Driving down the highway at 75mph able to hear the back seat passenger whisper versus having to talk loudly so the person in the front seat next to you can understand you.
A climate control system that keeps the car comfortable whether it is -20 degrees or 100 degrees.
Handling, brakes, and acceleration that is astronomically better than whatever your Chevette has.
There's no such thing as a "200mpg engine" - most modern car engines are very efficient, with the Prius's Atkinson cycle engine being the most efficient among worldwide-available, mass-production, affordable cars. It's a function of aerodynamics, parasitic electrical and mechanical losses, and weight.
> It's not all one thing or the other, and it never should be, but we've been milking the old internal combustion cash cow for so long we've virtually guaranteed her death, even though evolution of the internal combustion engine would be a net benefit.
Making an engine that would last 750,000 miles is certainly possible - just look at engines in big rigs - but people don't care about that in a personal vehicle, and the capex and opex for such an engine is incredible compared to the cost of making it significantly cheaper but slightly less reliable.
They want a low price tag and low maintenance during the period they own the car. That's why most engines have a 10k oil change interval (though part of that is due to much improved quality of oil, and better filters.)
Modern cars have improved drastically since 1981 by all metrics. Power, efficiency, safety, reliability, cost, and emissions have all improved. An amazing example of iterative refinement combined with economies of scale. If there is some cabal trying to keep cars inefficient and unreliable, they are losing.
My father drove a chevette. You neglect to mention the nearly 20 second 0-60 time, which on modern roadways is a safety hazard in itself. How much fuel did you burn just to get to that highway speed?
My Prius can easily do 60 mpg when driven on a flat road at highway speeds, and while it’s no speed demon in the quarter mile, it’s at least safe to operate. Plus it has more cargo carrying capacity and its vastly more pleasant to drive than a chevette.
Even my cheap dad got rid of that car as soon as possible.
People have been trying to find a better engine design for a long time. Pretty much all of them have tradeoffs of some kind, especially when you consider the wide variety of environmental factors that can affect a combustion engine.
Emissions is one thing, but performance is another big deal. Just look at a Volkswagen bug vs a modern car. Modern cars have 2-3 times the power and that comes at a cost. Another factor is safety.
If we agreed (not suggesting this for obvious reasons) that everyone would just build ultra lightweight and fairly low power vehicles, I think 80 mpg is feasible, but probably a lot less safe.
I work for General Motors and I occasionally do tours for employees. One of the cars I show is a 1950's era Pontiac Chieftain with an 4.4L inline 8 cylinder engine. It made about 120 horsepower. A modern, small-ish 1.4L inline 4 cylinder makes more horsepower.
A Beetle from the 50's might have 30-40 horsepower. You can pretty easily get cars with 10 times as much power now.
People are getting 80+MPG with hybrids. The standard EPA tests involve reasonably aggressive driving which is why the 1981 Chevrolet Chevette is only listed at 33 MPG highway.
I am not sure about Petrol Engines. However diesels at least they are typically tuned to run anywhere and on differing grades of fuel. However if you get your diesel car remapped you get better power and mileage out of car. I had mine remapped an extra 20hp (on a 95HP car) and the fuel economy improved quite a bit.
As for engines that last 40 years and 750,000. If you look after Diesel engines they can get to 500,000 or more. However people don't once the car gets over like 100,000 miles. Servicing costs typically more than the car is worth.
> don't want to make engines that can last forty years and 750,000 miles
Forty years is no problem already and a typical Honda/Toyota 4-cylinder engine is already a favorite to make 250K miles. Our CR-V just passed 225K miles and rust will kill that car long before mechanical problems do.
750K miles will cost you over $100K in direct operating costs (fuel and wear items). I don’t know that making an engine last 3x as many miles is that big a benefit to a new car buyer.
> Our CR-V just passed 225K miles and rust will kill that car
Modern cars are a marvel of cheapest manufacturing and materials. What would we accomplish if we optimized for corrosion resistance? It's not like we don't have the materials or processes. But they're nowhere as cheap as stamped sheet steel.
The problem is big oil and other huge corporations are paying off the politicans, and looking to exhaust the resources before moving on. The companies that destroy the enviroment want be the same companie's that own the next innovation. We know this from our own history. They know that if they make the best perduct today, one that there is no need to upgrade, they lose out on the revenue the constant upgrades produce. They live on the top of the hill looking down on the mess they make not having to deal with the pain and clean up. That is relagated to the poor. I say it's time for a corporate revolution. Break up all these companies, send the owners, (Stock holders) to a penal colony and let them fight for the same scraps they thought was enough for the rest of us. Time to take back our lives, if not all we will have to look foward to is death.
I don't know what kind of an idealist you are but you cannot break those companies. They are literaly the state. Look at the activities of CIA (for example) in the last century and see which companies profited from it. Google, Facebook, Microsoft are a threat _only_ if they threat the hegemony of the other (oil) companies.
Well, without any personal attack at all, I ask honestly, 'Who cares what you say?' Would-be agitators throughout history have tried to egg the masses on to societal nirvana. All we get in the end is jailed/murdered visionaries and a handful of kooks who think that destroying a few lives and a little property will spark the dawning of the new age.
There will probably continue to be a future for liquid fuels (especially for aviation) for quite some time, but ICE vehicles are only cheap because we can get fuel out of the ground and don't have to pay the energy or climate impact costs up front.
Battery-electric vehicles have such a huge efficiency advantage that I don't think ICE vehicles will ever be remotely competitive if you had to synthesize the fuel directly using renewable energy. A more efficient ICE engine (if it can live up to that claim) would be better than using old less-efficient engines, but I think we're at the point where the best option is not to use engines at all unless it's absolutely necessary for that application.
> I have a 1981 Diesel Chevette which can get 50 miles to the gallon when driven at a steady highway speed.
In a similar vein, my 2007 diesel Toyota Yaris regularly passed 60MPG and occasionally reached 70MPG before it was written off in an incident about 3 years ago.
This is the way. You are thinking like an engineer, and that will create solutions. Extracting carbon from the air, if done in a net-neutral manner (impossible with today's tech AFAICT), will provide us with sustainable hydrocarbons, nature's battery.
Part of it is weight. Safety standards and other things have really ballooned the the curb weight of cars. A Chevette weighed at most 2000lbs. A new Chevrolet Sonic (which is also a subcompact)? 2800lbs.+.
>I have a 1981 Diesel Chevette which can get 50 miles to the gallon when driven at a steady highway speed. If that forty year old fully iron engine can get 50 miles to the gallon in a car that's as aerodynamic as a brick, then why aren't new cars getting 80 miles to the gallon?
Because those modern cars have airbags, and thick pillars, etc, etc, etc and it's for your own good, peasant.
(also emissions, but modern tech to control emissions makes that a wash in the fuel economy department because said tech enables the engine to operate more efficiently on a per fuel basis)
The minimum viable car has gotten much safer, and much bigger. Reversing this trend and enabling right-sized vehicles will be one of the many benefits of autonomous vehicle technology and other active safety technology. Except for getting crushed like an insect, I don't need more than a vehicle weighing a few hundred pounds -- less than the weight of a Tesla battery -- for commuting. It would be less expensive and require less of everything, especially battery.
Are there really sliding seals that are good enough to contain a combustion reaction while handling an occasional redlining at 25,000 rpm, and capable of lasting for decades of service?
If so, then the fact that you can have two involute shaped mating surfaces as valves (almost no sliding, just a rolling contact), and a rotor that could be statically and dynamically balanced to almost zero vibration, would be amazing.
At this point, most of the parts of an EV are quite mature, and the overall system is a lot more straightforward than a conventional ICE car. A rear motor (or pair) can drive the real wheels without a transaxle or multi-speed transmission. Traction control can be achieved by rapidly adjusting torque. Regenerative breaking massively increases brake lifetime and reduces particulate emissions. 4WD is relatively inexpensive and increases efficiency (because the front and rear motors can be optimized for different operating regimes, and one can be turned off whole cruising). An electric A/C compressor can operate at the optimal speed for the A/C without regard for driving conditions. A small battery pack that can produce plenty of power for bursts of acceleration under anything except racing conditions is essentially a commodity.
So I think a series electric car with a 150kW (not kWh, and only supplying 150kW in brief bursts) and a small, highly efficient 30-40kW gasoline engine would be fantastic. And that engine would not need to have low efficiency and high emissions while warming up at low speed — when it turns on, it could immediately run at its optimal operating point even if the car is stuck in traffic.
Heck, a manufacturer could sell the engine as an optional feature — many customers could simply skip the engine and drive the car as a short-range EV.
The highest driving range for the longest range Tesla is 402 miles on a
full charged 100kWh battery pack. This is 4.02 miles per kWh.
A 30kW generator will produce 30kWh in an hour, which is enough energy to
drive 120 miles and well above any average travel speed required.
In ideal conditions a 20kW generator would be enough to drive with a
completely depleted battery at highway speeds, and a 10kW generator
would be enough to significantly extend your range.
Which might be necessary.. a 30kW generator running at fult tilt while
sitting at a stop light might be a rather unusual experience. Also
looking at commercial extended duty 30kW generators makes me wonder where
you're going to put that on an already 4,000lb car.
Exactly. Modern piston engines are great for dynamic loads but very inefficient because of it. Using engines to generate electricity in a single optimized configuration can greatly increase efficiency while benefiting from all the advantages of electric drivetrains. They can also be made modular to power everything from cars to boats to machinery.
This setup is already used in diesel-electric locomotives and submarines but hasn't really been applied to other transport systems for various reasons. It's something I've been working on as a side project although maybe it's time to launch it as a startup.
This is the second revolutionary ICE I have seen recently.
There was another that was also sort of like a Wankel. In it the triangular Wankel rotor is static, and the combustion chambers rotate around it. They have a working model with transparent parts so you can watch how it works.
Nothing in the Omega 1 presentation seemed to offer any clue how it works or why it is better.
These engines both seem like viable general-avition engines to replace Lycomings and Continentals, because electric is not really up to the job. FAA should take initiative to get these approved and deployed, because nobody can afford to do it privately.
Even better, these could be generation systems hooked up to an electric motor and energy buffer (battery). Put the prop on the motor, keep the whole transmission system electric, and stick one or more of these somewhere else making power.
You could put a little turbine in a Cessna or Beechcraft driving a generator and little-ish battery, and an electric motor driving the prop, and get the same benefit, but the cost and maybe weight would be higher in a place where both are critical.
Still, FAA probably should look into pre-approving such a configuration, too.
There are lots of interesting engine designs, but they almost always are either too difficult/expensive to make or unreliable outside of a dynamometer stand.
Sounds similar to experimental designs by Rolls Royce for a diesel rotary during the 60s, in that it uses two separate parallel shafts and rotors for intake/compression and ignition/exhaust.
> In the case of the Rolls-Royce Wankel Diesel, the fuel-air mixture is first compressed by the lower rotary, and the output of that engine (which would be like the exhaust valve of a conventional rotary) sends the compressed diesel/air mixture to the intake of the smaller upper rotary engine, where it’s compressed to ignite like a regular diesel engine.
Seems like it had the same issues that have always plagued rotaries, primarily with apex seals.
I don't get it. How is this engine going to save internal combustion? Ok, it's a small engine with a lot of power, and probably has some cute technical details, but what's the efficiency?
Almost one third of all greenhouse emissions come from transportation, which is the same as saying from ICE's. There are 2 ways to reduce that: replace ICEs with electric motors, or increase their efficiency. If you manage to double the efficiency of ICE's, you're doing as good as replacing half of the ICEs with electric motors. If you increase their efficiency by 20%, it's like replacing 20% of the ICEs with electric motors.
So, yes, you could certainly revive ICEs, but only if you dramatically increase their efficiency.
Now, a typical ICE has an efficiency of 25%. Nissan is working on an ICE with an efficiency of 50% [1]. That thing can save ICEs. Anything else, it's just word spinning.
I see no reason this thing wouldn't lose compression or backflow exhaust gas after wear-in, and wear-in would happen quickly with the cyclic load on those ball bearings. It's a pretty animation but unless they have some spring loading to press the upper and lower rings together the compression (and therefore efficiency) doesn't appear to be durable. There are also some limitations to having a single power stroke per revolution. This can be geared down, of course, but at an efficiency cost.
> There are also some limitations to having a single power stroke per revolution.
Unlike one power stroke per two revolutions? That engine has one stroke lasting a full revolution, modern four-stroke has power stroke lasting half of revolution, every two revolutions.
This is kind of vaguely similar to LiquidPiston's engine[1], which is sort of like a wankel engine turned inside out. (This has a couple benefits. The equivalent of apex seals can be on the non-moving part of the engine and thus are easier to lubricate. Also, the combustion chamber can be made more closely to spherical, which in theory should improve efficiency and emissions quite a bit.)
As of awhile ago, the LiquidPiston folks were working on improving longevity. Building a test engine that works is an impressive achievement, but getting it to last also requires a lot of careful engineering and testing.
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I have a 1981 Diesel Chevette which can get 50 miles to the gallon when driven at a steady highway speed. If that forty year old fully iron engine can get 50 miles to the gallon in a car that's as aerodynamic as a brick, then why aren't new cars getting 80 miles to the gallon? Is our technology really that shitty? Or is it that the carmakers have marketed performance and "sportiness" to us over efficiency?
They certainly don't want to make engines that can last forty years and 750,000 miles, but that's another issue.
So the real question is this: if we can have 80, 100, 150, perhaps even 200 mile-per-gallon combustion engines, and if we can grow biodiesel from algae and even produce it using processes which pull CO2 from the air, then how much energy and carbon output could we save by not building limited life batteries and by not suffering the waste of electricity transmission and storage?
It's not all one thing or the other, and it never should be, but we've been milking the old internal combustion cash cow for so long we've virtually guaranteed her death, even though evolution of the internal combustion engine would be a net benefit.
Old cars do well steady state, but are far less efficient in transient states; modern engines are far better at that.
Old cars have absolutely toxic emissions. I mean literal 100's of times worse than modern engines (especially diesels), which are already terrible.
Couple these two major factors and you'll see where most of the advances have gone. That said, I don't think you are completely incorrect either; incentives have to be put into the right places to drive these innovations forward.
If you want to see state of the art efficiency for fossil fuel engines look at trains. They are more heavily regulated for emissions than bunker fuel ships, and the amount of fuel per ton-mile used is tiny compared to a personal vehicle due to a few factors (load vs vehicle weight, efficiency of acceleration/deceleration, engines operating only at peak power/efficiency and the traction motors being electric, etc.).
On a side note, the lack of parts to keep an old car in compliance with emissions is driving me insane. My hobby car is a HUGELY popular car from 20-30 years ago and the supply of parts to keep it on the road is drying up already. Due to it's factory state of tune (naturally aspirated, ~100hp/liter) aftermarket discount parts are not suitable and fail quickly, sometimes damaging other parts. OEM parts are so rare now that they are getting painfully expensive to continue procuring them, and for emissions related systems the only quality parts left are the high end aftermarket (which aren't legal). It's becoming almost impossible to keep these vehicles legal, which I'm sure is intended. I'm at the point where I'll likely run the "illegal" (though perfectly identical if used properly) parts for 23 out of the 24 months it's on the road, and only use the almost impossible to obtain OEM parts for the 1 month needed to get it sorted for emissions testing.
> if we can have 80, 100, 150, perhaps even 200 mile-per-gallon combustion engines
Well, we can't.
Internal combustion engines have steadily gotten better, not stagnated.
In the 1970s, I heard all about oil companies buying 200 mpg carburetors to keep them off the market. My dad laughed at that, saying the military would never let patent law keep them from making 200 mpg tanks and stuff. Gas is a gigantic logistical problem for a mechanized military.
I've seen plenty cars get 300,000 miles here in Texas without a spot of rust on them. Do you live in Michigan or something? The salty states have only known rust and salt lol
I know nothing about that story, but the military is budgeted by Congress and commanded by the President, and thus subject to political influence. Plenty of the what the military does is inefficient economically and militarily.
https://www.cummins.com/news/releases/2021/07/30/us-army-awa...
Cummins and Achates Power was supposed to have delivered two working prototype engines to the US Army's TARDEC to be installed into a Bradley for evaluations in 2019. I'm assuming that they testing went well enough to prove that the engines are viable enough for further development.
Uncertain if the technology will ever meander it's way to regular car market, but interesting to see ICE development continue on.
https://www.youtube.com/watch?v=fPF4fBGNK0U
You causing more pollution (particulate, NOx, etc) than a hundred luxury SUVs or more, is the difference.
Driving down the highway at 75mph able to hear the back seat passenger whisper versus having to talk loudly so the person in the front seat next to you can understand you.
A climate control system that keeps the car comfortable whether it is -20 degrees or 100 degrees.
Handling, brakes, and acceleration that is astronomically better than whatever your Chevette has.
There's no such thing as a "200mpg engine" - most modern car engines are very efficient, with the Prius's Atkinson cycle engine being the most efficient among worldwide-available, mass-production, affordable cars. It's a function of aerodynamics, parasitic electrical and mechanical losses, and weight.
> It's not all one thing or the other, and it never should be, but we've been milking the old internal combustion cash cow for so long we've virtually guaranteed her death, even though evolution of the internal combustion engine would be a net benefit.
Making an engine that would last 750,000 miles is certainly possible - just look at engines in big rigs - but people don't care about that in a personal vehicle, and the capex and opex for such an engine is incredible compared to the cost of making it significantly cheaper but slightly less reliable.
They want a low price tag and low maintenance during the period they own the car. That's why most engines have a 10k oil change interval (though part of that is due to much improved quality of oil, and better filters.)
Deleted Comment
My Prius can easily do 60 mpg when driven on a flat road at highway speeds, and while it’s no speed demon in the quarter mile, it’s at least safe to operate. Plus it has more cargo carrying capacity and its vastly more pleasant to drive than a chevette.
Even my cheap dad got rid of that car as soon as possible.
http://www.douglas-self.com/MUSEUM/POWER/unusualICeng/unusua...
We'll have to see if this one does anything different.
If we agreed (not suggesting this for obvious reasons) that everyone would just build ultra lightweight and fairly low power vehicles, I think 80 mpg is feasible, but probably a lot less safe.
A Beetle from the 50's might have 30-40 horsepower. You can pretty easily get cars with 10 times as much power now.
Deleted Comment
As for engines that last 40 years and 750,000. If you look after Diesel engines they can get to 500,000 or more. However people don't once the car gets over like 100,000 miles. Servicing costs typically more than the car is worth.
Forty years is no problem already and a typical Honda/Toyota 4-cylinder engine is already a favorite to make 250K miles. Our CR-V just passed 225K miles and rust will kill that car long before mechanical problems do.
750K miles will cost you over $100K in direct operating costs (fuel and wear items). I don’t know that making an engine last 3x as many miles is that big a benefit to a new car buyer.
Modern cars are a marvel of cheapest manufacturing and materials. What would we accomplish if we optimized for corrosion resistance? It's not like we don't have the materials or processes. But they're nowhere as cheap as stamped sheet steel.
And yet, here we still are.
Battery-electric vehicles have such a huge efficiency advantage that I don't think ICE vehicles will ever be remotely competitive if you had to synthesize the fuel directly using renewable energy. A more efficient ICE engine (if it can live up to that claim) would be better than using old less-efficient engines, but I think we're at the point where the best option is not to use engines at all unless it's absolutely necessary for that application.
In a similar vein, my 2007 diesel Toyota Yaris regularly passed 60MPG and occasionally reached 70MPG before it was written off in an incident about 3 years ago.
Because those modern cars have airbags, and thick pillars, etc, etc, etc and it's for your own good, peasant.
(also emissions, but modern tech to control emissions makes that a wash in the fuel economy department because said tech enables the engine to operate more efficiently on a per fuel basis)
https://theicct.org/nox-and-co2-emissions-from-trucks-what-t...
A 2022 Corolla is ~3,000 pounds.
The Corolla has ~3x the horsepower.
If so, then the fact that you can have two involute shaped mating surfaces as valves (almost no sliding, just a rolling contact), and a rotor that could be statically and dynamically balanced to almost zero vibration, would be amazing.
At this point, most of the parts of an EV are quite mature, and the overall system is a lot more straightforward than a conventional ICE car. A rear motor (or pair) can drive the real wheels without a transaxle or multi-speed transmission. Traction control can be achieved by rapidly adjusting torque. Regenerative breaking massively increases brake lifetime and reduces particulate emissions. 4WD is relatively inexpensive and increases efficiency (because the front and rear motors can be optimized for different operating regimes, and one can be turned off whole cruising). An electric A/C compressor can operate at the optimal speed for the A/C without regard for driving conditions. A small battery pack that can produce plenty of power for bursts of acceleration under anything except racing conditions is essentially a commodity.
So I think a series electric car with a 150kW (not kWh, and only supplying 150kW in brief bursts) and a small, highly efficient 30-40kW gasoline engine would be fantastic. And that engine would not need to have low efficiency and high emissions while warming up at low speed — when it turns on, it could immediately run at its optimal operating point even if the car is stuck in traffic.
Heck, a manufacturer could sell the engine as an optional feature — many customers could simply skip the engine and drive the car as a short-range EV.
A 30kW generator will produce 30kWh in an hour, which is enough energy to drive 120 miles and well above any average travel speed required.
In ideal conditions a 20kW generator would be enough to drive with a completely depleted battery at highway speeds, and a 10kW generator would be enough to significantly extend your range.
Which might be necessary.. a 30kW generator running at fult tilt while sitting at a stop light might be a rather unusual experience. Also looking at commercial extended duty 30kW generators makes me wonder where you're going to put that on an already 4,000lb car.
This setup is already used in diesel-electric locomotives and submarines but hasn't really been applied to other transport systems for various reasons. It's something I've been working on as a side project although maybe it's time to launch it as a startup.
It seems like this thing could rev really high, since there's no herky-jerky motion.
There was another that was also sort of like a Wankel. In it the triangular Wankel rotor is static, and the combustion chambers rotate around it. They have a working model with transparent parts so you can watch how it works.
Nothing in the Omega 1 presentation seemed to offer any clue how it works or why it is better.
These engines both seem like viable general-avition engines to replace Lycomings and Continentals, because electric is not really up to the job. FAA should take initiative to get these approved and deployed, because nobody can afford to do it privately.
It seems to avoid the expensive fabrication a turbine needs for all those blades.
Still, FAA probably should look into pre-approving such a configuration, too.
> In the case of the Rolls-Royce Wankel Diesel, the fuel-air mixture is first compressed by the lower rotary, and the output of that engine (which would be like the exhaust valve of a conventional rotary) sends the compressed diesel/air mixture to the intake of the smaller upper rotary engine, where it’s compressed to ignite like a regular diesel engine.
Seems like it had the same issues that have always plagued rotaries, primarily with apex seals.
https://jalopnik.com/this-might-be-the-weirdest-engine-rolls...
https://youtu.be/1pDjwaqU0dU
I mention that because 60% efficiency on a 70F day requires a heat source of at least 900F.
https://www.omnicalculator.com/physics/carnot-efficiency
Deleted Comment
This one reason why, in piston engines, larger pistons ate more efficient. Less heat loss through the walls
Almost one third of all greenhouse emissions come from transportation, which is the same as saying from ICE's. There are 2 ways to reduce that: replace ICEs with electric motors, or increase their efficiency. If you manage to double the efficiency of ICE's, you're doing as good as replacing half of the ICEs with electric motors. If you increase their efficiency by 20%, it's like replacing 20% of the ICEs with electric motors.
So, yes, you could certainly revive ICEs, but only if you dramatically increase their efficiency.
Now, a typical ICE has an efficiency of 25%. Nissan is working on an ICE with an efficiency of 50% [1]. That thing can save ICEs. Anything else, it's just word spinning.
[1] https://www.greencarreports.com/news/1131416_nissan-claims-5...
Unlike one power stroke per two revolutions? That engine has one stroke lasting a full revolution, modern four-stroke has power stroke lasting half of revolution, every two revolutions.
As of awhile ago, the LiquidPiston folks were working on improving longevity. Building a test engine that works is an impressive achievement, but getting it to last also requires a lot of careful engineering and testing.
[1] https://news.ycombinator.com/item?id=25450477