Free Piston range extender
Discussion
Can i ask how many production passenger car engines you have designed developed and homologated Moto?
(because i know the answer to that in the case of AER.....)
The issue with all these "new" technologies is that they are "too little, too late". Let me explain.
The day that battery technology improves by approx another 30 to 50%, is the day that ALL internal combustion engine energy converters become obsolete. This is because once you reach ZERO tailpipe emissions every single environmental issue / problem and COST simply become SEP! (Someone Else's Problem)
With EU6+ emissions design development and then homologating costing upwards of £100M per platform, moving to a fully electric car cuts costs to such a degree that no OEM can afford not to do it.
Think of the range of issues that go away completely, and soon, having ANY kind of engine is going to become seriously un-cool. And the savings just keep on coming, for example, On Board Diagnostics, and conformity of production simply disapear, because when an electric car breaks down it does not pollute (unlike say an ICE with a misfire). Cat ageing, DPFs, DMFs, SCRs, Urea injectors, high pressure common rail pumps, evaporative emissions, multiple drive cycles, testing on world wide fuels at a huge range of temperatures, thermosat monitoring, misfire monitoring, catalyst monitoring, injector ageing, etc etc etc all simply disappear, saving MILLIONS!
So, if i asked you for say £200M to develop a new world beating ICE architecture, you would rightly say "what are the risks"? and the risk is that your idea becomes a white elephant over night.......
(because i know the answer to that in the case of AER.....)
The issue with all these "new" technologies is that they are "too little, too late". Let me explain.
The day that battery technology improves by approx another 30 to 50%, is the day that ALL internal combustion engine energy converters become obsolete. This is because once you reach ZERO tailpipe emissions every single environmental issue / problem and COST simply become SEP! (Someone Else's Problem)
With EU6+ emissions design development and then homologating costing upwards of £100M per platform, moving to a fully electric car cuts costs to such a degree that no OEM can afford not to do it.
Think of the range of issues that go away completely, and soon, having ANY kind of engine is going to become seriously un-cool. And the savings just keep on coming, for example, On Board Diagnostics, and conformity of production simply disapear, because when an electric car breaks down it does not pollute (unlike say an ICE with a misfire). Cat ageing, DPFs, DMFs, SCRs, Urea injectors, high pressure common rail pumps, evaporative emissions, multiple drive cycles, testing on world wide fuels at a huge range of temperatures, thermosat monitoring, misfire monitoring, catalyst monitoring, injector ageing, etc etc etc all simply disappear, saving MILLIONS!
So, if i asked you for say £200M to develop a new world beating ICE architecture, you would rightly say "what are the risks"? and the risk is that your idea becomes a white elephant over night.......
Max_Torque said:
The day that battery technology improves by approx another 30 to 50%, is the day that ALL internal combustion engine energy converters become obsolete.
That is stating the obvious. 
We all know the IC engine has little time left. We know that battery and ultracapacitor technology is improving like wildfire. Look at battery advances. It was not so long ago mobile phone batteries were like bricks. Look at them now, they can run small computers all day. A smart phone battery on just a cell phone that only does phone calls will last for weeks. Look at power tool batteries! An SDS drill can drill a largish hole through a brick wall on one battery charge. Great for men up ladders. Japan has introduced battery powered urban trains, that take a small top-up charge at each station stop, and a full charge at the terminus. This is viewed to massively reduce costs by eliminating full line electrification. Bombardier in the UK is doing battery train trials. The view is to use mains electricity from overhead wires or a 3rd rail at each station to accelerate the train from halt, and the batteries take it along to the next station. The DfT is looking very closely in order to use these battery trains to extend underground urban rail networks like London, Liverpool, Newcastle and Glasgow onto low passenger usage unelectrified track; high passenger usage justifies full line electrification. They will not allow diesel engines and their fuel tanks into underground stations and tunnels.
The point is that batteries are now small and hold a big charge. Battery and ultracapacitor R&D is big and newer superior batteries with much faster charging are in the pipeline for sure. If the advancements continues at the rate of the past 15-20 years EVs will be the norm in 15 years time. Most autos sold in the developed world will be EVs.
Any range extender is viewed to be an interim measure for sure, as all are expecting batteries and/or fuel cells to greatly improve over the next decade. But the likes of Toyota and Mazda can also use these small auto generators as small luggable generators in no-auto applications (note Toyota are talking about one cylinder free piston units which can be doubled up for larger vehicles; just add another genny). Mazda has muttered about using wankels for luggable usages to keep production numbers up. The free piston and wankel designs are small and light, just what is needed for these applications. So, their investment will not be wasted by pouring millions into IC/genny R&D. When the auto industry sheds these range extending IC units and moves over to full EV there is always a market for these small generators, so R&D money is not wasted.
Edited by motorlad on Tuesday 13th January 11:32
motorlad said:
Lotus have also made a dedicated range extending 3 cyl piston/crank engine which is to be produced in Spain. These are all ready when other makers turn to full series-hybrids setups. The BMW 2 cyl motorbike engine in the i3 used a range extender is rather a cobbled together affair only to get you home slowly.
When we tried to buy one, the Lotus/Fagor engine wasn't available given its largely unvalidated status at the time. The inverter used with the system would be kindest to describe as motorsport-focussed, and was a long way behind some of the competition in terms of meeting accepted automotive standards. The "cobbled together" i3 lump on the other hand, is production validated with pukka power electronics.Given the small volumes of range-extended electric vehicles, pursuit of the technically perfect solution is not the aim of the game - it's delivering a reliable and cost-effective APU/range-extender unit that has at least reasonable efficiency. Clearly in something with poor EV-only range the ICE efficiency becomes more important, but in the i3 where the APU is a "limp-home" device, why burden the project with huge development costs to recover by re-inventing the wheel in the pursuit of every last drop of efficiency?
motorlad said:
AER said:
It's not an insult unless you want it to be. Every post you add makes it a clearer point of fact, however.
It is insulting for sure, even 996TT02 pulled you up on it. You are a know-it-all, unsure of yourself so start insulting at the first step and repeating the insults. Intelligent people do not have your attitude. You cannot get your head around anything new or any deviation from the status quo. You are not worth engaging with as you add zero. You probably make your living from regrinding crankshafts.Write to Toyota and tell them they haven't got a clue.
I note, however, that whilst you feel insulted by a statement of fact, you singularly fail to address any point I raise, like fundamentally the fact that 42% thermal efficiency is no better than 90's diesel technology.
Interesting that you think the IC engine has little time left. If this is true, why would anyone bother to invest money into high risk ideas like free piston engines? I actually think it's probably worth the risk, but to believe there's a huge leap in efficiency to be had is misguided. There are some potential packaging advantages and possibly some manufacturing advantages, but they won't come for free or risk free. Toyota have the resources to play about with this stuff but a large part of this is marketing and image-making as much as fundamental research.
I actually don't entirely share Max's view on the future of IC engines in that I believe the "if" of whether battery technology makes huge leaps forward is a big "if" indeed. The capability certainly needs to improve by a factor of 2 or so to pose any risk of decimating the IC engine. Note that steam power hasn't gone away after all these years, although open-cycle steam is only for the nostalgia buffs and children. Rather it has found its niche in power generation and nuclear submarines. I think the IC engine will retreat to its niche in long-distance road transport over the years to come.
Part of the problem of EVs conquering the IC engine will continue to be the charging infrastructure. It's one thing to recharge a relatively efficient, low rolling resistance passenger car in 20-30mins every 2 hrs with Elon's superchargers, but when your power demands grow to accommodate larger and commercial vehicles, so too will the power requirements and/or time taken to recharge. The US EPA's restricted 10 gallon/min gasoline fill rate is still the equivalent of a 19.5 megawatt power station! Imagine what a high-flow diesel bowser represents. Getting even close to these power levels to EV recharging stations will be quite a challenge.
On the other hand, the relatively miserable utilization of cars means that for commuting purposes EVs will shine and 100 mile ranges will be a problem only in peoples heads rather than reality. For the 95 percentile purposes we use cars for today, EVs will become the norm over time.
AER said:
Well, that's a great ad hominem. Normally people resort to such methods when their arguments have failed.
Some resort to insults when they are insecure and have failed arguments. I am not arguing with you. Toyota on the first run got 42% and are confident of getting far more. Please do not bring up nonsense like the K series or large heavy diesel engines. Toyota's range extender is very small and light and can fit in a spare wheel well.
Read Max's and my posts again. You never got much of it.
Charging infrastructure will improve as EVs are introduced. I don't think anyone would be so foolish as to think it will stay static. Also, as EVs become more common, petroleum fuel distribution will tail down to the point it will be difficult to obtain roadside fuel, meaning large trucks will become EVs. The price of petroleum fuel will rise. Even ships may be hybrids with dockside charged battery banks and physically small range extenders. Large diesel engines take up valuable cargo/passenger space. Ship can be clad in solar panels.
AER said:
EVs will shine and 100 mile ranges will be a problem only in peoples heads rather than reality.
You got that right Edited by motorlad on Tuesday 13th January 11:38
amstrange1 said:
Clearly in something with poor EV-only range the ICE efficiency becomes more important, but in the i3 where the APU is a "limp-home" device, why burden the project with huge development costs to recover by re-inventing the wheel in the pursuit of every last drop of efficiency?
The i3's range extender is a cobbled together joke, it limps the car home. It is an old piston/crank motorbike engine. The Chevy Volt's range extender engine is an off-the-shelf motor not designed for such applications and is not fully suitable for the task in hand. Toyota and Mazda are looking at dedicated designs for specific applications; producing only electricity for range extending EV's.Your attitude is not to advance and make do. I find this attitude and view too typical of the modern British. You are not alone. Most of the posts here are wanting to keep hopelessly inefficient 19th century technology going, shunning and sneering new developments. The British are a race that catapulted the word forward in technology at one time. Pretty sad really.
stevieturbo said:
Batteries are improving ???
Your Smart phone is a small palm sized computer. Look at the batteries we had 15 years ago. If you want only an old type cell "phone" to have a lasting battery, one is available. The battery can last for about a week or more.Edited by motorlad on Tuesday 13th January 11:40
motorlad said:
AER said:
Well, that's a great ad hominem. Normally people resort to such methods when their arguments have failed.
Some resort to insults when they are insecure and have failed arguments. I am not arguing with you. Toyota on the first run got 42% and are confident of getting far more. Please do not bring up nonsense like the K series or large heavy diesel engines. Toyota's range extender is very small and light and can fit in a spare wheel well.
Read Max's and my posts again. You never got much of it.
Charging infrastructure will improve as EVs are introduced. I don't think anyone would be so foolish as to think it will stay static. Also, as EVs become more common, petroleum fuel distribution will tail down to the point it will be difficult to obtain roadside fuel, meaning large trucks will become EVs. The price of petroleum fuel will rise. Even ships may be hybrids with dockside charged battery banks and physically small range extenders. Large diesel engines take up valuable cargo/passenger space. Ship can be clad in solar panels.
AER said:
EVs will shine and 100 mile ranges will be a problem only in peoples heads rather than reality.
You got that right Edited by motorlad on Tuesday 13th January 11:38
And it's the same story for prime movers. Because of their mass and size, they always operate at significant load, and hence there is no efficiency gain to be had from load leveling, like in a passenger car hybrid. No, what is happening for commercial vehicles is conventional ICEs with Exhaust Heat Recovery! Because they are expensive, large and powerful, the manufacturers can fit EHR systems, something that is not yet viable for passenger cars.
Then we get to statements like "the range extender engine fits in the spare wheel well" etc. Great and all that, but plenty of motorcycle engines are of similar small size, with significantly higher output, and it's all the "extras" like the inverter & cooling pack etc that all eat up space
Right now i'm working on passenger car programs that reach SOP in MY16, MY18, and even MY2020, and exactly none of those are using any non standard architecture piston engine.
Max_Torque said:
LOL, now we are into the realms of fantasy! Ships clad in "solar panels"?
You should really read the points put across which is not difficult rather than trying to mock advancement and be funny. 19,000 containers on one ship to Hull? Now that is funny. There is only about two in the world that size and they cannot get into Hull. Solar panels on ships can easily run the ship's ancillaries, using the batteries as a buffer. Motorcycle engines with crankshafts will not have the efficiencies of a small free piston genny. Please keep up
It looks like piston engines with cranks, hopelessly inefficient Victorian technology, will disappear. You may need a career change. stevieturbo said:
Why dont they use the opposing pistons combustion to compress the other sides ?
Stevie, This is one way to return opposed pistons.http://www.unimodengines.com/technical.html
Two levers and the gas is remote from the pistons in a shock absorber. The electrical coils can be in this remote cylinder. The levers can have stops to prevent pistons from crashing into each other or the ends of the cylinders.
What no one has noticed is that power is generated, via the electrical coils, on the downstroke "AND" the upstroke of the piston in the Toyota and Germany's "NASA" free piston generator engines. In a piston/crankshaft engine energy is only generated on every other one of the downstrokes in a 4-stroke cycle and only on the downstroke of a two-stroke cycle. Efficiency has to be greater.
amstrange1 said:
When we tried to buy one, the Lotus/Fagor engine wasn't available given its largely unvalidated status at the time. The inverter used with the system would be kindest to describe as motorsport-focussed, and was a long way behind some of the competition in terms of meeting accepted automotive standards.
Interesting. If you do not mind me asking, what were you wanting to do with this small light range extender? Edited by motorlad on Tuesday 13th January 20:02
motorlad said:
The i3's range extender is a cobbled together joke, it limps the car home. It is an old piston/crank motorbike engine.
Scooter engine actually... Pedantry aside, it's reliable, proven technology - which is what an established OEM needs in such a situation. Someone like Tesla can and does take more risks, they don't have profitable sales of the 320d that might be affected if their innovations turn out to be dangerous or unreliable.As I said, BMW's design criteria were to have an APU as a limp-home device, if you're regularly hammering the s
t out of your range extender/APU on long journeys arguably you've bought the wrong powertrain for the job.It's not about living in the dark ages, most of the OEMs have pretty innovative (and/or odd!) stuff happening behind closed doors - and sometimes they like to shout about it like Toyota have. But just because they've done some testing and published a few papers doesn't mean the technology is ready to hit a car showroom next month. Development cycles in automotive are hugely slow when compared to other technology such as smart 'phones - but this is driven by the need for robust validation given the safety risks involved.
amstrange1 said:
motorlad said:
The i3's range extender is a cobbled together joke, it limps the car home. It is an old piston/crank motorbike engine.
Scooter engine actually... Pedantry aside, it's reliable, proven technology - amstrange1 said:
It's not about living in the dark ages, most of the OEMs have pretty innovative (and/or odd!) stuff happening behind closed doors
A pity we have not seen it and doubt we ever will. Edited by motorlad on Tuesday 13th January 20:10
motorlad said:
Solar panels on ships can easily run the ship's ancillaries, using the batteries as a buffer.
You can put solar panels on the roof of your car, and charge the battery whilst it's parked, but that is also not financially viable (ie the cost of the panels is more than the tiny amount of energy "saved"). So yes, putting panels on large ships may help say a few tonnes of oil per trip, but they are never going to replace an ICE as the prime mover, having to push a 50,000 tonne ship through water.motorlad said:
Motorcycle engines with crankshafts will not have the efficiency of a small free piston genny. Please keep up It looks like piston engines with cranks, hopelessly inefficient Victorian technology, will disappear.
What has a "crankshaft" got to do with it? The frictional loses of an oil film supported crank shaft are tiny. There isn't any fundamental improvement in thermal efficiency just because all the motion is reciprocal? It looks like piston engines with cranks, hopelessly inefficient Victorian technology, will disappear. motorlad said:
You may need a career change.
Really.motorlad said:
What no one has noticed is that power is generated, via the electrical coils, on the downstroke "AND" the upstroke of the piston in the Toyota and Germany's "NASA" free piston generator engines. In a piston/crankshaft engine energy is only generated on every other one of the downstrokes in a 4-stroke cycle and only on the downstroke of a two-stroke cycle. Efficiency has to be greater.
What everyone has noticed is that unfortunately you have no idea what you're talking about. "Efficiency" is not a measure of specific power. The "Efficiency" doesn't have to be "greater", and in fact, the "stop start" coil motion means your inverter system is extremely compromised if you only have one piston/coil set. This is because the differential velocity between the coils is zero at each end of the stroke, at which time the output power is zero. As a result to achieve the same RMS output voltage you need to wind the coils for Root3 times more voltage at the peak velocity point (mid stroke), as as electrical loses are the square of the peak load, your overall system efficiency is LOWER, than for a conventional rotational generator where the power is temporarily s£mechanically" stored in the inertia of the rotor.Then you need to look at the fact that because of this sinusoidal velocity profile, your inverter power correction and EMC filters must be bigger, more expensive and with a higher loss (ie lower efficiency). To over come these issues you need a 120degc Phase offset synchronised multi(3) piston arrangement, all of which is convieniently done by, yup, that pesky crankshaft in a normal engine. That "dumb" lump of iron, which does all that, cheaply, and incredibly efficiently, and acts as a power storage/low pass filter at the same time.
Oh, and while on the subject of "Linear generators" pray tell me how you intend to keep the rotor precisely in the middle of the stator coils?
Hint, magnetic force increases with the inverse square of the distance, so to avoid the rotor getting "stuck" on one side or the other of the stator, you need large and very stiff bearings at each end of the rotor. And those bearings have loses, just like, oh yeah, the bearings that support, yup, you guessed it, a crankshaft......
(The biggest frictional loss in any engine is the piston rings sliding again the bores under gas loading, something "Free piston" engines do nothing about).
Hint, magnetic force increases with the inverse square of the distance, so to avoid the rotor getting "stuck" on one side or the other of the stator, you need large and very stiff bearings at each end of the rotor. And those bearings have loses, just like, oh yeah, the bearings that support, yup, you guessed it, a crankshaft......
(The biggest frictional loss in any engine is the piston rings sliding again the bores under gas loading, something "Free piston" engines do nothing about).
Max_Torque said:
motorlad said:
Solar panels on ships can easily run the ship's ancillaries, using the batteries as a buffer.
You can put solar panels on the roof of your car, and charge the battery whilst it's parked, Your job is on the line. Once again you may need a career change.
Max_Torque said:
What everyone has noticed is that unfortunately you have no idea what you're talking about.
You deal with hopelessly inefficient, antiquated Victorian technology. Not only that you are a know-it-all who knows nothing. You cannot absorb simple points. When you are cornered, which is easy to do, you insult. If you know anything about propulsion you make a reasoned argument, however you cannot. You struggle even with simple concepts. You are a very negative person. Get yourself sorted.You have little of electric generation.
Edited by motorlad on Wednesday 14th January 00:26
motorlad said:
AER said:
Well, that's a great ad hominem. Normally people resort to such methods when their arguments have failed.
Some resort to insults when they are insecure and have failed arguments. motorlad said:
I am not arguing with you. Toyota on the first run got 42% and are confident of getting far more. Please do not bring up nonsense like the K series or large heavy diesel engines. Toyota's range extender is very small and light and can fit in a spare wheel well.
Have you read the SAE paper this quote of yours comes from? I'm pretty sure the "first run" quote is bks. I have been involved in running several prototype engines for the first time and I can tell you, measuring thermal efficiency isn't very high on the priority list! And as they used HCCI to achieve this, I can assure you it would have taken them some time to get this operational. In any case, if they achieved 42% on their "first run", how is it they didn't make any advancement on this subsequently and report it in the same SAE paper?Oh, and by the way, none of the pictures of this Toyota engine show how the valve actuation works, nor any inlet or exhaust system. Add these things and watch the packaging volume grow...
motorlad said:
Read Max's and my posts again. You never got much of it.
I can assure you. Max and I are singing from the same sheet. No need to try to bring him in as your long lost buddy.motorlad said:
Charging infrastructure will improve as EVs are introduced. I don't think anyone would be so foolish as to think it will stay static. Also, as EVs become more common, petroleum fuel distribution will tail down to the point it will be difficult to obtain roadside fuel, meaning large trucks will become EVs. The price of petroleum fuel will rise. Even ships may be hybrids with dockside charged battery banks and physically small range extenders. Large diesel engines take up valuable cargo/passenger space. Ship can be clad in solar panels.
You clearly have no idea of the power consumption of large vehicles and ships and how this compares to the feeble capacity of batteries and available charging systems. And, if we become EV dependent in short order, I can assure you that the price of petroleum fuels will fall and dramatically so compared to all-time-highs we have seen. Have you noticed how cheap LPG is? This is mostly because supply outstrips demand and it's a byproduct of distillation of oil to produce the more valuable products. This will happen to gasoline too, if the dominant fuels used becomes kerosene, diesel and electricity. I doubt economics will allow this scenario to play out though because EV's will be forever pushing against falling fuel prices.Edited by AER on Wednesday 14th January 00:32
Max_Torque said:
(The biggest frictional loss in any engine is the piston rings sliding again the bores under gas loading, something "Free piston" engines do nothing about).
A two-stroke free piston does not have the dead pumping loses of piston/crank arrangements. Anyone who knows about engines will tell you that. And power is generated on both strokes of the piston in Toyota's free piston engine. You cannot understand something so simple.Get out the business. Have you tried delivering milk?
Edited by motorlad on Wednesday 14th January 00:44
AER said:
motorlad said:
AER said:
Well, that's a great ad hominem. Normally people resort to such methods when their arguments have failed.
Some resort to insults when they are insecure and have failed arguments. I am not arguing with you. Toyota on the first run got 42% and are confident of getting far more. The "first run" is b
ks is it. Prey tell. Now do make things up as you usually do. You have been involved in running several prototype antiquated Victorian technology engines. No more.
I know exactly what power ships consume. Believe me.
Edited by motorlad on Wednesday 14th January 00:43
motorlad said:
I know exactly what power ships consume. Believe me.
Please can you explain what your educational background and experience are so we can understand how you can speak with authority.Max Torque has a very sound engineering background and a wealth of experience. We've seen his projects on this site. Insulting him is in danger of undermining your credibility without at least some evidence to support what you are saying.
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