GAS-L: OT, Flywheel battery eff, was Re: GAS-L: Fuel Cells

[jerry dycus <jerry5335@yahoo.com>]

      Hi Arnt and All,
--- Arnt Karlsen <arnt@c2i.net> wrote:
> On Mon, 28 Jan 2002 09:00:46 -0800 (PST)
> jerry dycus <jerry5335@yahoo.com> wrote:
> > > >      A good EV can get up to 20% eff from the
> > > power
> > > > plant fuel to the road. 
> > > 
> > > ..with todays power plants, agreed. 
> >         With the TECO coal gasifier power plant
> that I
> > get my power from it's probably 25/28% because
> it's
> > 60% eff by using the gas to power a gas turbine
> then
> > using it's exhauts to run a steam boiler to make
> more
> > electricity. 
> >       I'm trying to get them to burn some biomass
> with
> > the coal but they are coal people and TECO owns
> it's
> > coal mines too.  
> 
> ..the _big_ money is in coal.
   SO true!!
> 
> >       They are going to experiment with 10%
> biomass in
> > a DOE experiment soon and I will try to get them
> to
> > keep doing it after the tests are done.
> >         I've talked to them about introducing
> steam
> > into the gasifier bed to convert the leftover
> carbon 
> > to make more H2 and CO fuel, but haven't been able
> > talk them into it yet. I think if they did eff
> might
> > rise another 5%.
>  
> ..cool.  Prove it.  ;-) 
      I'm going by what comes from my Mark's Manual
from the 20's. The reaction is called water gas and
adds extra fuel in the form of H2 and CO from the
steam/carbon plus heat.
     Since the carbon and it's heat are about to be
wasted, dumped in the ash pit, this is extra fuel at
the cost of some steam made from the waste heat of the
turbines exhaust.
> 
> > > > > Ehum. Not comparable. A flywheel is a
> storage of
> > > > > (close to?) 100% pure work.
> > > > > Ottos and diesels are heat motors. Heat is
> never
> > > > > 100% work, you know. ;)
> > > >       But where does the flywheels energy come
> > > from?
> > > 
> > > ..from "my" coal + MSW fired gasifier fuel cell
> > > loop, 
> > > eventually at 93%.
> >     How? If you convert coal/MSW to H2 it's about
> 50%
> > eff then the fuel cell is about 50% eff you are
> down
> > to 25% or less and you haven't driven the car yet.
>    
> 
> ..today, yes.  The other half is doing the same with
> the CO.
> _Tomorrows_ coal + MSW fired gasifier fuel cell loop
> uses 
> fuel cell exhaust heat to drive most of the
> gasification.  
> Which is why it must loop.  I estimate about 3.5 - 4
> times.
     I hear a rule of thumb is that it takes about 10%
of the biomass'/coal's energy to gasify it. That means
10% is as much as you can save, not 3 or 4 times as
much.
     One way they are using the fuel cell heat is to
replace the fuel burners in a gas turbine with the
fuel cell's waste heat to power the turbine. This
could make fuel cell/turbine combo 75% eff. The navy
is testing it now. So use your loop to run a Rakine
heat engine or  process heat.

> 
> >    Also you have to use energy to store the H2 or
> > electricity losing more energy, then the electric
> > drive system , electric in to ground, is between
> 70 to
> > 85% eff. 
> 
> ..no, the idea is to store the energy either
> upstream, 
> as coal, or, downstream, in the flywheels.  
> Flywheels also soak up shock loads such as grid
> transients.
    For stationary this might work but the principal's
have been known for years and no sucessful units are
running. The rotating mass of the generators do this
function some from their flywheel effect.
> 
> ..and, you don't want to store poisonous H² + CO
> gas, at all.
> 
> > > > What eff was it made at? While flywheels sound
> > > good
> > > > they have many problems in a car.
> > > > > 
> > > > > Beats a chemical battery though?
> > > >     Not in eff or cost. A lead/acid battery
> can
> > > charge
> > > > 
> > > > elect in /elect out at 95/ 97% eff and with a
> > > rundown
> > > 
> > > ..what???  Usually I hear around 60-70%.
> >      While true for NiMH batts, lead acid batts
> with
> > good chargers do quite well as above, nicads are
> about
> > 93% eff due to self discharge. 
> 
> ..my experience is automotive starting batteries
> only, where I have 
> experienced an average 50 full charge cycle life.  I
> am also aware 
> that submarines has used lead cells since before
> WWI, however these 
> 50 cycles also match a reasonable submarine combat
> life expectancy.
      While this is true of car starting batts deep
cycled, good deep cycle batts go 1000 to 5000 cycles
depending on how you treet them.
      A diesel/electric sub on a war footing would go
2 cycles a day and their batts are good for about
5000+ cycles because of many reasons like light
discharge loading, pure lead, ect.   
> 
> >    My prefered battery for EV use is Ni-cads. They
> > have a good power/weight ratio, long life of
> 50,000 to
> > 100,000 miles and will give my scratch built ev a
> 150
> > mile plus range. 
> 
> ..neat.  Scratch built ev???  Url?
       Put Freedom EV into yahoo and it should come
up.
> 
> ..my experience is good NiCd cells do around 60%. 
> Scaling up 
> could add some, but cadmium is a future no-no heavy
> metal, which 
> is phased out in favor of metal hydrides, which
> initially, doubled 
> cell performance, as in 1100 mAh against 500 mAh in
> AA size cells.
       We are talking about different ni-cads. I'm
talking about flooded ni-cads in 100 amp/hr sizes. 
       Ni-cads last much longer cycle wise and are
much more tolerent of abuse than NiMH batts in EV's.
They cost 1/5 and last 3000 to 5000 cycles. Cadmium
isn't a problem as they are rebuilible or recycled.
     I hope you recycle your's. 
> 
> > > > of 4 months while the flywheel will lose all
> it's
> > > > energy in 2 or 3 days and would be lucky to
> get
> > > 92%
> > > > eff not counting where the electricity comes
> from

> > > ..I use Jack Bitterly's flywheels as my
> baseline. 
> > > 96%.
> >         Does he include how much energy is lost to
> > friction while it's waiting to be used? Even good
> > flywheels will lose 1% per hr of running, most
> much
> > more.
> >     Does he include the controller losses which
> would
> > be at least 5% besides the flywheels motor/gen
> losses.
> 
> ..afaik, yes and yes.  Friction should also be
> air/gas 
> friction in the vacuum box, and magnetic bearing
> losses.  
> His "black box" charge cycle efficiency is 96%.
    From what I know of motors, controllers and
friction this is impossible. Eff in the real world
would be lucky to be 90%, more like 80/85% if you have
a lot of thru-put. If it has to sit around waiting to
be used the eff goes way down from friction losses.
                     jerry dycus

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