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

[Arnt Karlsen <arnt@c2i.net>]

On Thursday 31 January 2002 13:09, jerry dycus wrote:
>       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.

.."Gengas" states 8%.  Now, this heat does not have to
come _from_ the coal.  It only needs to _get_there_.  
Which is _why_ we loop back the fuel cell heat.  
Since nothing works 100%, we try again 3.5 - 4 times.  ;-)

>      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.

..and you forget the gasifier here.

..losing heat boiling the water and not being able to 
reduce the fuel cell exhaust, that concept would fail.

> > >    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.

..yep.

> > ..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.

..assuming no combat damage etc, agreed.  
1.4 years is reasonable, 7 sounds very optimistic.

> > >    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.

..read up on Cadmium and heavy metal policies, Cadmium has no future.
I agree NiCd is much more mature, so it should beat the early metal 
hydrides.

> > > > > 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

..well, that's Jack's headache, not mine.  ;-)
I use his flywheels as a baseline until they've been beat.

..and, this too, I heard, is impossible:  ;-)
http://solstice.crest.org/discussion/gasification/199903/msg00055.html

-- 
..med vennlig hilsen = with kind regards from Arnt...  ;-)

  Scenarios always come in sets of three:
  best case, worst case, and just in case.

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