Go Back  GreenHybrid - Hybrid Cars > Central Information Center > Hybrid & Related News
“Extreme” Plug-In Flywheel Hybrid Promises a Possible 250 MPG >

“Extreme” Plug-In Flywheel Hybrid Promises a Possible 250 MPG

Hybrid & Related News New cars, press releases, articles and more. Reply only. Have news?

“Extreme” Plug-In Flywheel Hybrid Promises a Possible 250 MPG

Old 02-23-2005, 01:55 PM
Site Founder
Thread Starter
Join Date: Dec 2003
Posts: 4,623
Default “Extreme” Plug-In Flywheel Hybrid Promises a Possible 250 MPG

AFS Trinity Power Corporation has unveiled a flywheel-supported hybrid technology that the company anticipates will enable fuel economy in the 200–250 mpg range.

The Extreme Hybrid drivetrain—under development for light duty and heavy duty vehicles—is a plug-in hybrid that gets most of its power from the grid. The flywheel system provides greater efficiency in energy capture and release from regenerative braking, thereby extending the operational range of the vehicle in all-electric mode.
- http://www.greencarcongress.com/2005...xtremerdq.html
Old 02-23-2005, 05:43 PM
Hot_Georgia_2004's Avatar
Ridiculously Active Enthusiast
Join Date: Mar 2004
Location: Atlanta, Ga
Posts: 1,797
Default I'm skeptical.

Last year I did quite some research on flywheel energy storage devices. They are truly fascinating in the right application.

Flywheels work wonderful as short-term power backup systems for computers, etc, they can even supply temporary backup power for entire buildings, provided the mass is large enough, and how many are employed.

There have been quite a lot of research in flywheel powered cars for years, here are just a few "roadblocks" they have encountered:

1. In order to achieve a 100 mile traveling range it would need to store enough kinetic energy that if it were released all at once in an upward fashion, would hurl a ~3Klb vehicle around 10 miles straight up.
2. Flywheels occasionally fly apart. It's usually quite a large explosion when the incredible energy is suddenly released from a larger one. In order to ensure safety these large units are installed in the ground.
3. The flywheels do not rotate on ball bearings. The bearings are magnetic and provide zero resistance because the shaft "floats" in a magnetic field. Even if mounted in a gimble it is not enough to overcome the shake of an automobile, as this magnetic field is compromised.
4. In the case of an automobile accident, there is real danger of a heavy flywheel becoming unstable and exploding, causing further injury, death and/or destruction.
5. Please forgive, but I've forgotten the techical name for the nature of a Flywheel to resist crosswise rotation. They've used this property for decades in guidence systems, etc. This was another problem they found associated with flywheel powered autombiles.

I admit not reading the article with its technical descriptions, as I don't really want to register at that website.
I know the flywheel in this car isn't its only power source but I find it hard to believe that they have overcome all the related problems well enough to provide a safe vehicle.

Guess this is a "Just wait and let's see" kind of thing.

Last edited by Hot_Georgia_2004; 02-23-2005 at 07:44 PM.
Old 02-23-2005, 07:15 PM
Join Date: Dec 2004
Location: Leominster, MA
Posts: 2,161

Is a flywheel similar to the thing they put in wind up toys?
Old 02-23-2005, 07:39 PM
Hot_Georgia_2004's Avatar
Ridiculously Active Enthusiast
Join Date: Mar 2004
Location: Atlanta, Ga
Posts: 1,797

Not wind up, that would use a spring.

A spinning top is an example of a flywheel.
My son had a flywheel based car that you put in a base and turned a crank, spinning the wheels faster, faster and faster. The flywheel inside would make quite a noise as it spins to store the energy from the crank. Then you'd let it go and it zoomed across the floor.

Commercial flywheels are sealed in a vacume of special gas to reduce friction, made of a composite material and as mentioned uses special zero friction magnetic bearings. These flywheels used for energy storage range in size from about a foot square to much, much taller ones.

Probably the most widely used flywheel storage sytem is for computer power back-up system. Typically it would provide enough time for a proper shut down of many computers connected in a network.

The idea is to use an electric motor to gradually spin a heavy flywheel up to speed, then maintain that speed. Imagine 50lbs or so spinning at several hundred thousand RPM's.
When the power goes out the motor converts to a generator (Like our cars electric motors do) and runs the backup system for computers, etc.

If you do a google search on flywheels the reading can be fascinating.

Last edited by Hot_Georgia_2004; 02-23-2005 at 08:04 PM.
Old 02-24-2005, 02:33 AM
Pretty Darn Active Enthusiast
Join Date: Aug 2004
Posts: 302

Other than the safety issues, the other downside to flywheels is the low specific energy (ie you'd need a heck of a large flywheel to give a car any real range).

AFS appear to be using them for their peak-power benefits though, to take the strain off the batteries (though I think ultracaps would do a better job of this and keep things a lot simpler).
Old 02-26-2005, 10:22 PM
Join Date: Apr 2004
Location: Biloxi, Miss
Posts: 20
Smile windup hybrid battery

If you can windup a radio for about two mintues and it will play for about an hour. Is it possible that this could work on a Hybrid?
But only as a backup. Lets say you forget to check your gas gauge and you don't have enough gas to make it to a gas station. The rule I read is don't drive your Hybrid, on the battery without gas in the tank. If you had something like a windup, this could be enough to get you to the nearest gas station.
Old 02-06-2009, 08:57 AM
Join Date: Sep 2007
Posts: 6
Default Re: “Extreme” Plug-In Flywheel Hybrid Promises a Possible 250 MPG

Flywheels work wonderful as short-term power backup systems for computers, etc, they can even supply temporary backup power for entire buildings, provided the mass is large enough, and how many are employed.
True enough, but if you think about it the flywheel has been used for years in our cars for this very type of application. After all it is the flywheel that does three quarters of the work, namely, exhaust, compression and intake, only the power stroke is due to actual power from the engine.
All the problems you talk about can be overcome quite easily providing an engine with a rotary output is available. This is why flywheels work effectively with electric motors and not with any other type of engine. The Wankel engine has an eccentric output, not a rotary output, and so is even more inappropriate for use with a flywheel than an IC piston engine with its linear to rotary conversion type of output.
Flywheels are being used today in Formula 1 racing. They have been extensively tested for safety (Google flybrid) but unfortunately are used only in the regenerative braking as a race car enters the pit stop. Now imagine what would happen if you had an engine that could bring the flywheel upto speed and then switch off. It need not be a very heavy flywheel, for instance a 10 Kg flywheel spinning at 40,000 rpm would generate about 3.5 MJ of KE, enough to run a car weighing 1200 Kg for 20 minutes or so ! OK, so there are problems with precession, the solution to this is to have two identical flywheels facing each other and spinning in opposite directions or set the whole thing on gimbals. The present flybrid system which will be used in Formula 1 racing from this season, weighs 5 Kg and spins at a staggering 64,000 rpm, it has been extensively tested for safety. As for an engine to power the flywheel, the Rotary Pulse Jet Engine is probably the solution. This engine uses rocket power in a way that was envisioned by Robert Goddard, as an intermittently firing engine. If you don't believe me he took out a patent for his idea. The Rotary Pulse Jet Engine, does away with pistons, cylinders, camshafts, push rods, crankshaft, in short everything except the combustion chambers and the drive shaft. The Rotary Pulse Jet will be far more powerful than any IC piston engine and will bring the flywheel upto speed in a very short space of time.
Calculations and commonsense, for instance a 1700 GTR Mitsubishi reaches 100 Km/h in just uder 3 secs, show that it should be possible to bring the flywheel up to speed in about three seconds, the savings in fuel would be huge much greater than the 250 -300 mpg talked about. Further the car would be able to go anywhere it would not be tied down to the grid.
Since the engine works for only a few seconds in every 20 minutes or so, there would be no problem with cooling etc., also the RPJ does not use oil. So all in all this is something good that should be looked into.
Old 03-21-2009, 07:11 PM
Join Date: Apr 2005
Posts: 43
Default Re: “Extreme” Plug-In Flywheel Hybrid Promises a Possible 250 MPG

How does a high speed power storing flywheel in a car avoid acting as a gyroscope and resisting any attempts to redirect (turn) the car? It would seem this could be an issue...
Old 03-26-2009, 01:59 PM
FastMover's Avatar
Old Boomer Techie
Join Date: Jun 2007
Location: Pacific Northwest (WA)
Posts: 572
Default Re: “Extreme” Plug-In Flywheel Hybrid Promises a Possible 250 MPG

After a read of the article, I am given to understand that a primary claimed value of the flywheel is the ability to act as a surge buffer during moments of high energy recovery during dynamic braking or during high current demand as in full acceleration.

It seems to me that the emerging supercapacitor/ultracapacitor technology offers the potential for an efficient electronic buffering equivalence to the flywheel without the problems or losses associated with a mechanical device.


I am a skeptic when it comes to a vehcile powered only by an ultracap package in any reasonable timeframe. However, a hybrid using both ultracaps and Li-Ion batteries would seem to me to be feasible and econmically acheivable within the next decade or so.
Old 03-26-2009, 06:11 PM
SoopahMan's Avatar
Pretty Darn Active Enthusiast
Join Date: Sep 2006
Location: North Hollywood, CA
Posts: 374
Default Re: “Extreme” Plug-In Flywheel Hybrid Promises a Possible 250 MPG

Flywheels are a cool way to store and release kinetic energy.

They continue to be cool when you put them into a car to capture braking energy and release drive energy.

They get very uncool when that car hits a bump, and the flywheel resists movement perpendicular to its rotation, causing the car to basically collide with the flywheel as it jolts upwards and the flywheel remains in place.

The only thing that might reference this is the idea of a flywheel inside a flywheel to resist gyroscopic action but it's stated pretty vaguely, and I'm not sure rotating one inside the other eliminates the issue... I'm pretty sure you have the exact same problem, just split into 2.

Thread Tools
Search this Thread
Quick Reply: “Extreme” Plug-In Flywheel Hybrid Promises a Possible 250 MPG

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.