> > Still not sure we're on the same page. I think having a single ratio
 > > drive to the regen generator/motor is perfectly adequate - a cvt or
 > > other variable ratio drive is not necessary. The bulk of the energy
 > > available is going to come from slowing from a high speed. The regen
 > > energy available from a slow speed is negligible.
 > >
 > > Storing energy to a flywheel certainly requires a different approach
-
 > > accelerating the flywheel while decelerating the car.
 > >
 > >
 > > Regards,
 > >
 > > Matt-
 > >
 > >
 > > Well You could be right. Maybe we don't have to change the ratio.
 > > How do you propose speeding up the flywheel as the car slows?
 > >
 > > Paul Lamar
 >
 >
 > Like I said.. The all mechanical storage system (flywheel) requires
 > something different. If weight weren't a concern, I'll bet an
 > electric-electric system would be as efficient as anything else - the
 > wheel motors become generators while braking, driving a motor which
 > mechanically turns the flywheel - probably gear the flywheel to turn
 > faster than the motor. It might be difficult to design a motor which
 > would survive at the RPM required to make the flywheel efficient
 > (v-squared term dominates). It could be worth trying though as
 > integrating the motor into the flywheel would dramatically simplify
 > the system.
 >
 > The electrical portion of the system is reversed to recover power from
 > the flywheel.
 >
 >
 > Matt-
 >
 > Well we shall see as weight is everything in a Formula 1 car.
 >
 > Paul Lamar
 >

Paul and Group,

Here is a link to a Kinetic Energy Recovery System by *Torotrak and
Xtrac*.  The web site says it weighs about 11 lb.



http://www.torotrak.com/Marketing+information/Press/Torotrak+and+Xtrac+announce+new+Licence+Agreement+for+F1+Variator+development.htm

Norm DeBoer

"Some of the new KERS systems under development will be mechanically
based
and will utilise a flywheel to recuperate, store and subsequently
discharge
a moving vehicle's kinetic energy, which is otherwise wasted when the
vehicle is decelerated. The kinetic energy is stored during a braking
manoeuvre and is then released back into the driveline as the vehicle
accelerates.

The toroidal traction drive variator, being developed with Torotrak and
using Torotrak's patented technology, is a central element in these
mechanical flywheel-variator KERS systems as it provides a continuously
variable ratio connection between the flywheel and the vehicle driveline,
via the vehicle's gearbox. Torotrak has granted a licence to Xtrac to
design, manufacture, assemble and distribute components or complete
variator
systems, which incorporate Torotrak's technology, to its F1 customers.

The innovative combination of a Torotrak variator â?? providing
mechanical
efficiency that should be in excess of 90 per cent - with a flywheel of
advanced construction, results in a highly efficient and compact energy
storage system. Whilst Xtrac will supply variator units to its customers,
the flywheels for these energy recovery systems are being developed
separately by the Formula 1 teams themselves and their specialist
suppliers.
Torotrak will provide the control system expertise.

Torotrak and Xtrac believe that the variator-flywheel solution provides a
significantly more compact, efficient, lighter and
environmentally-friendly
solution than the traditional alternative of electrical-battery systems.

"The variator weighs less than 5kg [11 pounds] in these applications and
provides a high level of mechanical efficiency, enabling the overall mass
of
the mechanical KERS systems to be minimised," says Chris Greenwood,
technology director at Torotrak. "This mechanical efficiency, combined
with
the variator's ability to change ratio very rapidly, helps to optimise
flywheel performance."


Beats the heck out of the silly 300 or 400 pound electricity system in
the
Toyota Prius and GM Volt.

Paul Lamar

I wish them all the best.  But...  They don't seem to have any actual
product, and they are asking for people to send them money (investment
op).  Doesn't that violate your rules?


Matt-

Perhaps but there certainly is  a market as KERS is required by Formula 1
rules.
So far nobody else has stepped up to the plate as far as I can tell.
Since Toyota is spending $800 million a year on the F1 program they are a
likely customer. Any kind of electricity solution uses batteries and
Toyota
kills the energy storage per pound by not allowing the Prius batteries to
be
discharged below 40% or charged above 80% so the batteries will last
longer
than a couple of years. Beside any electricity solution will not approach
90% efficiency
as there are too many conversions from on form to another. E=IR
If it were not for R electricity would be a better solution but that is
asking
for perpetual motion :) BTW GM states you will never see the Volt unless
new
battery technology is developed.

Paul Lamar

Err..  Who said the electrical solution will use batteries?  That was
you..  :)  I'm saying to use the motors as transmissions, not for
charging batteries but to drive and be driven by the flywheel.  Please
read my posts...  I know they're boring..  :)

Matt-

Yes my mistake. Sorry Matt. You propose to spin up a flywheel with a motor
at best 80% efficient, powered by a generator at best 80% efficient and feed
it back into the wheels with  another motor at best 80% efficient. Overall
efficiency is 50% while the mechanical KERS is 90% efficient. I just threw
the battery stuff in there because I just learned about it.  It had nothing
to do with what you said.

Paul Lamar