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Discussion Starter · #1 · (Edited)
Audi has a Wankel for a range extender. 148.7 mpg (imperial)

Audi A1 -click

Below: the Wankel is so small it fits under the trunk floor:


Audi A1 - report -click

Audi has confirmed the A1 e-tron will be made using the Wankel range extender.

A1 to be made -click

GM did heavy Wankel research in the 1960-70s, saying they solved the fuel problem at the time - but not saying how. They have to start up the R&D again.

The Wankel is durable for sure. The seals issue is now an urban myth. They perform better at high revs in mpg, which means it is ideal for a range extender. At high revs they are still smooth and quiet. They are also smaller with a superior power/weight ratio, which gives great packaging

AVL have developed a range extender package:
AVL Wankel range extender - click




Toyota have been quiet on their future hybrids. They can't keep with the Prius setup. They must be planning a new hybrid system.
 

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Discussion Starter · #3 · (Edited)
The Prius will continue to outsell all other alternative fuel / propulsion vehicles combined for several more years. Meanwhile, Toyota continues to develop their fuel cell technologies.
The Prius will be leader until the Volt and others get on-line. Then it will fade.

The small Lotus range-extender will make it easy for retro fitting a series hybrid into a makers existing bodyshell. You may find some makers will get a series-hybrid on-line quite quick as Lotus responded proactively to the market.

If Toyota are playing around with hydrogen they may be on the wrong track. Fuel cells have been developed using gasoline.

The British Department for Transport advised the last government not to get involved in expensive cross-country overhead wire electrification projects as fuel cell technology appeared to be advancing fast and may lend itself viable for trains. In short, wait a few years and see, as the diesel locos may be replaced with a superior technology not needing hundreds of miles of overhead lines.

About 18 months ago they dropped this view, after pressure from rail groups, and full electrification projects were announced replacing diesel trains. Electric trains do not need fuel storage and the facilities to refuel the trains. They are lighter as they do not carry heavy engines and fuel and safer in tunnels. Brake regen is easy. But they need maintenance teams to see to the countless miles of overhead wires and support stanchions. Electrifying hundreds of miles of track is not cheap at all, although the train maintenance and running side is a lot cheaper.

So, have Toyota made a break-through?
 

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John,
I like that little Wankel unit too. I'd like to see a somewhat different approach to EREV. I would like to see 100 mile AER and a very small, light and inexpensive range extender that would hardly ever be used.

Fuel consumption would not be such a big issue w/ such an EREV.

Probably not a terribly practical solution but interesting none the less. (I guess I'm just trying to get something a little more suited to my driving cycle.)
 

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Discussion Starter · #7 · (Edited)
Wankels are fuel efficient at their revving sweet spot - which is high revving. Make them operate at the sweet spot constantly and slap on alternator. The compact size and weight then makes them shine and the ideal choice.

An EV that has a long battery powered range is more concerned with a compact range extender rather than its fuel efficiency, as it will be rarely used.
 

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Discussion Starter · #8 · (Edited)
Orbital designed two-stroke engines meet emissions standards and are made in the millions for scooters, boats, etc. They also have some high hp engines that can easily power a car. Using one of these engines as the genny on a Volt will improve matters greatly. It is far smaller and far more efficient when run at its constant speed "sweet spot" - emissions improve as well. The power/weight ratio is far superior to the great clunk GM put in the Volt. The Volt then could be made like it was intended - with electric drive only.

Orbital and Hirth....

Orbital-Hirth two-stoke

Lotus, who have an off-the-shelf genny engine for hybrids (far batter than the Volts), also are looking down the two-stroke route.
Lotus Two-Stroke

Some background to Orbital's engines
 

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GM did develop several Wankel engines, and had one version running in a prototype Corvette and one in the 1974 Vega. Here is some information:
http://en.wikipedia.org/wiki/General_Motors_Rotary_Combustion_Engine

NSU in Germany developed the first automobile with the Wankel engine in 1964 (the German husband of my mother's cousin was the only person I knew to have actually worked with the NSU Wankel a few years before Mazda produced their first Wankel engine), and now it is a part of Audi. We all know the history of Mazda success with the Wankel rotary in the RX series. I have know about the Wankel since 1966 (and with that German guy), and later built the Renwal Visible Wankel Engine model.

So I believe that the Wankel with modern materials can recover its position as a better substitute for the Otto-cycle piston engine that the Volt and other EREVs will have. I wish Audi much success, and I wish that more manufacturers follow their progress to join the EREV generation.

Raymond
 

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Discussion Starter · #10 ·
GM did develop several Wankel engines, and had one version running in a prototype Corvette and one in the 1974 Vega. Here is some information:
http://en.wikipedia.org/wiki/General_Motors_Rotary_Combustion_Engine

NSU in Germany developed the first automobile with the Wankel engine in 1964 (the German husband of my mother's cousin was the only person I knew to have actually worked with the NSU Wankel a few years before Mazda produced their first Wankel engine), and now it is a part of Audi. We all know the history of Mazda success with the Wankel rotary in the RX series. I have know about the Wankel since 1966 (and with that German guy), and later built the Renwal Visible Wankel Engine model.

So I believe that the Wankel with modern materials can recover its position as a better substitute for the Otto-cycle piston engine that the Volt and other EREVs will have. I wish Audi much success, and I wish that more manufacturers follow their progress to join the EREV generation.

Raymond
Raymond I agree, the Wankel has come a long way. A long way from 1974. GM are way behind I would assume - they need to do some R&D fast. Running it at a constant speed at its sweet spot makes them far more efficient and the perfect choice for a quiet, small, fuel efficient range extender. This is where the big auto giants should be looking - small, quiet, nearly vibration-free and economical.
 

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Wankels are well known to have poor fuel economy.

the only advantage of Wankel...
compact, for its power output.

if AER is 100 miles,
poor fuel economy might not matter.

...................................

fuel cells are crap, and always will be.
the reason Honda blabs so much about fuel cells,
is that they don't want you to buy an electric car.
Honda is totaly about building gasoline engines
(which they are very good at)
But don't believe a word they say
 

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Discussion Starter · #12 · (Edited)
Wankels are well known to have poor fuel economy.

the only advantage of Wankel...
compact, for its power output.

if AER is 100 miles,
poor fuel economy might not matter.
You forgot many other advantages, such as:
  • high revving,
  • quiet,
  • simple,
  • reliable,
  • simple to fix,
  • few parts which means cheaper to make in mass production,
  • etc

Running it at a constant speed at its most efficient sweet spot makes them far more fuel efficient and the perfect choice for a quiet, small, fuel efficient range extender.

Wankels have poor economy in the constantly changing revving operating conditions in current ICE auto usage. They tend to be more economical on faster revs, hence why Mazda only make a sports cars with the engine. The Russians have helicopters with wankels in them.
 
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