HDTenEightyP/NetNews huggingface dataset:
From: spang@calstatela.edu (Sue P.)
Newsgroups: sci.energy
Subject: Thanks for the responds RE: Solar Energy
Date: 19 Nov 92 04:33:38 GMT
Reply-To: spang@calstatela.edu
Organization: Cal State University, Los Angeles


Hi,
I just wanted to thank you (you know who you are) for your professional critisims regarding the post I've sent out earlier on "Solar Energy."  I don't have a chance to go through them yet.  I'll follow up with a post as soon as all of my midterms are over.

Sue
Newsgroups: sci.energy
From: mancus@zaphod.JSC.NASA.GOV (Keith Mancus/MDSSC)
Subject: Re: More External-Combustion Info
Organization: nasa-jsc
Date: Tue, 17 Nov 1992 20:51:49 GMT

In article <1992Nov17.180135.25760@kakwa.ucs.ualberta.ca>, sherwood@space.ualberta.ca (Sherwood Botsford) writes:
 
> 2.  Some of these 30 second boilers work as 'flash boilers'   Flame heats
> a plate, and the water is sprayed on.  With some work, I bet that you could
> trade increased fuel consumption for faster heating.
 
  Sure, just have two heating systems..  The "pilot" system heats
it quickly and inefficiently, then the efficient system takes over.

> 4.  I think that the original reason Stanley's had pilot lights was to keep 
> the boiler from freezing in winter.  Some clever design is called for here, 
> with either pilot light and/or systems that self drain into a holding tank
> won't get bent out of shape by freezing, and could be warmed easily with
> either a plug or a torch.  
 
  I can't believe this is a big problem, but only a chemist/chemical
engineer could say for sure.  We solved this problem in gasoline recips
by creating antifreeze; although existing antifreezes may interfere with
the steam cycle, can't we develop some other chemical additive?

> 6.  One of the claimed advantages of the Stanley Steamers was their noise.
> They were very quiet.  This would be a big selling point with me.  They
> were also very simple mechanically, although messy in terms of plumbing.  
> I think the entire drive train had 24 moving parts.
 
> 7.  One of the big advantages of steam is the idling efficiency.  You
> use very little fuel sitting still.  This could be significant for trucks,
> busses, and city delivery vehicles.
 
  Given the large mass, slow acceleration, high torque, low noise, etc...
I would say that the initial version should be a replacement for large diesel
trucks (everything from small Macks to 18-wheelers).  This looks like a
near-perfect solution, provided that the efficiency is high enough.
And I HATE getting behind trucks belching choking black smoke!!!

> Questions:
 
> 3.  Given a closed system is there a better choice of working fluid than
> water (Something that wouldn't freeze, and could act as a lubricant.)
 
  For some applications, like these "commuter" cars that the electric crowd
is pushing, you might want to keep the loop open and eliminate the radiator/
condenser and associated weight.

> => Sherwood Botsford                   sherwood@space.ualberta.ca <= 
> => University of Alberta         Lab Manager, Space Physics Group <=         
> => tel:403 492-3713                             fax: 403 492-4256 <=         

-- 
 Keith Mancus    <mancus@cheers.jsc.nasa.gov>                           |
                 N5WVR                                                  |
  "If I owned Texas and I owned Hell, I'd rent out Texas and live       |
  in Hell." -General Sheridan                                           |
From: 01crmeyer@leo.bsuvc.bsu.edu (Craig Meyer)
Newsgroups: sci.energy
Subject: Re: Continuing Steam-Car Discussion
Date: 23 Nov 92 18:08:14 GMT
Organization: Ball State University, Muncie, In - Univ. Computing Svc's


>>> Steam engines normally use the wet steam as a cylinder lubricant. 
>>> No additional oils are required. The "rings" are normally leather
>>> wetted by the steam. In old locomotives, they lasted 6 months of
>>> *continous* hard pulling between servicing. Remember that a piston
>>> steam engine develops maximum torque at stall and is a low RPM 
>>> device. Bearing lubrication can be a simple drip oiler.

> Well stationary plants that operate at 800C don't use lubricants in the
> steam because they use turbines. Hopefully there's no metal to metal
> contact in areas reachable by the steam. In old piston plants, as I noted, 
> they used the wet steam as a lubricant. I suspect that GM was trying to use
> ordinary IC engine rings and thus needed lubricants in the steam.

You're probably right.  But using leather at high superheats (which seem
necessary just to get the thing to be efficient) look like bad news.

If a two-stroke (not double-acting) piston engine were used, what of
lubricating the piston by spraying WATER on the cylander walls 
below the piston?  (Above the piston would be the hot steam, and below it,
would be the cool water being sprayed on the cylander walls)  Some lubricating
water would leak into the steam system, but that's not a problem.

But as was mentioned, would this not work anyway if we were using 
metal piston rings?
 
> The other issue with high superheats is how do you generate them?
> A flash boiler probably won't do. That means the boiler and the
> superheat exchanger would be much larger, startup time would go
> from 30 seconds to several minutes, and much more live steam would
> be in the system making it more dangerous in a collision.

Tell me if this makes sense:
Imagine two concentric tubes, each of SLIGHTLY different diameter (the space
betwen them is very tight).  Pump the water through the space between the
tubes, and send the fire down the middle of the smaller tube.

A cross-section would be:
Outer tube:steam:inner tube:fire:inner tube:steam:outer tube.

By further shrinking the space between the tubes, you could produce a 
very low volume/high surface area boiler.  You could make this 
"steam-wall boiler tube" very long, and bend it into compact, 
rectangular shapes.  Could this hint at an advance in
boiler technology?
 
> Gary
-- 
       Craig Meyer                 01CRMEYER@LEO.BSUVC.BSU.EDU
       Indiana Academy for Science, Mathematics, and Humaities.
       Muncie, IN  47306                          317-285-7433

       Opinions expressed are mine alone, and not necessarily
       shared by the Indiana Academy.
Newsgroups: sci.energy
From: drickel@bounce.mentorg.com (Dave Rickel)
Subject: Re: External-Combustion Cars -- Possible?
Originator: drickel@bounce
Date: Tue, 17 Nov 1992 01:35:25 GMT
Organization: Mentor Graphics 
Keywords: 
Followup-To: 


In article <1992Nov12.111359.11804@bsu-ucs>, 01crmeyer@leo.bsuvc.bsu.edu (Craig Meyer) writes:
|> Could a fuel-burning, zero-emmisions vehicle be built if it were driven
|> by an external-combustion engine?

Somone mentioned Stanley Steamers.  I think that the Steamers were an open
system--that the steam was exhausted rather than cooled and recondensed and
reused.  I seem to remember something like 10 miles per gallon of water.
Going to a closed system has some major impact on cooling and radiator area
and annoying things like that.

Steam cars would seem to have some problems in colder climates.

People seem to like to jump in their cars and drive away--they don't take well
to waiting a couple of minutes to build up a head of steam (too many spy
films, perhaps).

One of the big three (Ford?) spent quite a bit of money investigating Stirling
cycle engines back in the 70's; Popular Mechanics or Popular Science had an
issue or two about that.  I think Detroit's eventual conclusion was that
an external combustion vehicle had too many moving parts--that it would be
too expensive to manufacture.  If the California law about zero emissions
were changed to a low-emissions law, so that an external-combustion engine
might qualify, there might be a chance of resurrecting this research.


david rickel
drickel@sjc.mentorg.com
Newsgroups: sci.energy,sci.environment
From: gary@ke4zv.uucp (Gary Coffman)
Subject: Re: opening of the first self-sufficient solar house, Press Release
Reply-To: gary@ke4zv.UUCP (Gary Coffman)
Organization: Gannett Technologies Group
Date: Fri, 13 Nov 1992 07:08:26 GMT

In article <JMC.92Nov12102403@SAIL.Stanford.EDU> jmc@cs.Stanford.EDU writes:
>In article <1992Nov12.124743.23938@bernina.ethz.ch> eric14@bernina.ethz.ch (Eric Baltischwiler) writes:
>
>   On independance from the power grid...
>
>   : >>Is it thought to be desirable to not use the electric grid?
>   : 
>   : You can assign a cash value to freedom from the grid. Grid power costs
>   : around $.10 per kWh in many areas of the US. The array in the German
>   : house provides about 40 kWh per day, or about $4 worth of electricity
>   : at grid prices per day. The house cost DM 1.6 million. At current mortgage
>   : rates of 8%, that's 350 DM per day for *interest alone*. Now I don't know 
>   : the current exchange rate, but I'm sure that 350 DM is more than $4. And
>   : you still won't ever own the home free and clear unless you attack that
>   : 1.6 million principal.
>
>   The point to remember here is that this is a research project!  As a
>   deminstration it is very effective to isolate the house from the power
>   grid.  If you are looking at producing "real" houses then the design
>   goals would be different.  Parts of the design could be cheeply
>   implemented and parts not.  Clearly the pasive heating ideas are
>   usefull today.  Just as clearly going for zero outside power use is
>   not cost effective if you are building in normal setting.
>
>There are research projects and there are publicity projects.

And both have their place. I think the German experiment is worthwhile.
I don't think abandoning the grid willy nilly is sound policy, but as
Eric notes, this is a *demonstration* project. It shows what's currently
possible. And more to the point, it demonstrates what is, and what isn't,
economically sound. Leaving the grid isn't economically sound with the
technology demonstrated in the home, but the super insulation and Trombe
wall construction does make it *possible*. Those features of the home
can be utilized *without* leaving the grid. There have been a number of
experimental solar houses constructed around the world. Most have highlighted
unforeseen difficulties with super insulation construction. It will be 
interesting to follow the operation of this home to see if the problems
of humidity buildup, and toxic build up in the interior air have been
solved.

Gary
Newsgroups: sci.energy
From: gary@ke4zv.uucp (Gary Coffman)
Subject: Re: Info on the GM SE-101 Steam Car
Reply-To: gary@ke4zv.UUCP (Gary Coffman)
Organization: Gannett Technologies Group
Date: Mon, 16 Nov 1992 17:23:09 GMT

In article <1992Nov13.223911.25528@aio.jsc.nasa.gov> mancus@carla.JSC.NASA.GOV (Keith Mancus/MDSSC) writes:
> [stuff deleted]
>  Interesting stuff.  Obviously it needs more development work, but I
>think this is a more promising area than those silly electric cars.  (Sorry
>folks, I am far more suspicious of battery technology than most of you
>are.  I'll believe it when I see cheap, relatively lightweight mass-market
>batteries with energy storage comparable to a tank of gas.)

Don't hold your breath. :-)

>Questions that your material might be able to answer:
> -Why did they use a piston steam engine instead of a geared-down turbine?
>  Gearing problems?  Cost of the turbine?

Steam piston engines develop max torque at stall. That simplfies gearing
a lot. Turbines are more expensive, and don't work well over wide RPM
ranges, requiring complex gearboxes. It's also wasteful to have the
turbine spinning while idling at a stop, and you have to, or you'll have
unacceptable throttle lag while the turbine spools up. A steam piston engine 
doesn't demand *any* steam when stopped. With flash boilers, less than a
teacup of steam is in the system at any one time. That means you can 
throttle the heat source immediately, saving fuel. Finally, a piston
engine offers the advantage of dynamic braking for free. That's not a
small consideration.

> -You didn't say what they used as fuel.  Propane?  Natural gas?  Seems
>  like you could use just about anything liquid or gaseous and not too
>  corrosive, which could be a big advantage.

The Stanley Steamer used heating oil. Any flamable liquid or gas would
work, including peanut oil. Saturated steam temperature isn't very high,
however, so the Carnot efficiency isn't wonderful, hence fuel economy
isn't wonderful. If you could superheat to 800C, it'd be great, but that
brings on another host of problems you don't want to tackle outside a
large stationary plant.

Gary
From: ems@michael.apple.com (E. Michael Smith)
Newsgroups: sci.energy
Subject: Re: Electric car question.
Date: 22 Nov 92 17:10:26 GMT
Organization: Apple Computer Inc, Cupertino, CA

In article <sundermm.70.0@columbia.dsu.edu> sundermm@columbia.dsu.edu (MARC SUNDERMEYER) writes:
>	I was wondering how many people would be willing to buy an electic 
>car if it were powered by a nuclear reactor.  (The reactor would connected 
>up in such a way that its contents wouldn't come out in the event of a 
>crash.)

It would depend a lot on the particular technology.  Something like a 
SNAP generator, packaged like for the space program, I'd buy.  Something
like a BWR sans concrete containment with melt down potential, I'd pass...

Key Issues:  1)  Structure such that physical abuse might make chunks
of it, but not release {gas, liquid, or dust} that was radioactive.  That
is, no product that was subject to natural transport away from a crash site.

2)  Structure such that a fire could not cause release of radioactives.
That is, each 'chunk' from a crash site should be inert in a gasoline
fire.  

3)  Fuel 'bundle' such that fuel recycling/reprocessing is 'easy'.  I do
not like the idea of burying partly used fuel bundles and calling it 
waste disposal (as we are planing now for commercial reactors).  Make
sure that the fuel bundles are re-processed to removed the long lived
isotopes that make good fuel and only bury the short lived isotopes that
are most radioactive but decay in the shortest time.

4)  A 'nice to have':  fuel bundle such that they are self sheilding.
That is, if the {what, lead?} reactor shield is broken open in a crash
the fuel elements are not lethal to a rescue worker...  This implies
either one heck of an interesting fuel element structure or a reaction
that produces few/no neutrons and gammas...  This may be an imposible
constraint to meet in something that would fit in a car, ask the 
nuke engineers here, they know their stuff.

Summary:  If it doesn't pose a crash hazard, or a fuel handling/waste
disposal hazard, I'd buy one.

How large would a properly packaged 10 kW SNAP generator be?

Any way to make a HTGR of a 20 kW size with fuel pellets that are,
oh, marble sized,and with a fire proof chemistry?


-- 

E. Michael Smith  ems@apple.COM

'Whatever you can do, or dream you can, begin it.  Boldness has
 genius, power and magic in it.'  -  Goethe

I am not responsible nor is anyone else.  Everything is disclaimed.
From: stead@skadi.CSS.GOV (Richard Stead)
Newsgroups: sci.energy
Subject: Re: Renewable Energy - solar
Date: 16 Nov 92 17:27:48 GMT

In article <XX5SBJHH@cc.swarthmore.edu>, dpeders1@cc.swarthmore.edu (Daniel Pedersen) writes:
> Richard Stead mentioned that not all places are like So.Cal - some of them
> have clouds.
> 
> On a partly cloudy day, our data shows that when the sky is overcast, the
> beam component drops by a large amount, and the diffuse radiation
> increases.  I can explain this by assuming that the beam component striking
> the clouds is converted to diffuse radiation.  When the normal beam
> radiation dropped to zero, the diffuse radiation rose to 250 and even 300
> W/m^2.  So there is a large amount of radiation available even on overcast
> days.  (for reference, during the sunny parts of this day the values of the
> different forms of the radiation were close to the values listed above).

I have a question - is it possible that some of this energy is infrared
radiation being radiated from the earth's surface and the objects on it that
were heated while the sun was out?  True - this is still recoverable solar
energy, but I am curious if your number would change significantly on a
day which was completely overcast at all times.  This is not unusual.
I just spent two weeks near Moscow, and I did not see the sun the entire
time.  Nevertheless, I agree that even diffuse solar energy may have
some role in satisfying energy needs - supplying hot water for heating
and whatever is probably the most promising.

> So while I disagree that the alternative energy forms are as unreliable as
> the author of the paper states (sorry, forgot your name!), I also disagree
> with Richard when he writes off solar energy because of cloud cover.  My
> prof says that his research shows that a solar collector system can be 
> viable in the Philadelphia area, which is often cloudy.

I'm sorry - I really didn't mean to give the impression I was anti-solar.
I'd like to think I'm pro-solar, I even did a solar energy "research" in
high school.  I just don't think it's a panacea, nor do I think it can
provide for a majority of our energy needs.  I think it ought to be
applied when practical, with balanced consideration of all factors.

> We are now running a heating system simulation on the collectors (hot water
> + antifreeze), and have had some cloudy days.  At the end of next week we
> should have some good results regarding the performance of the collector as
> a heating source.

Please let us know how it turns out.


--
Richard Stead
Center for Seismic Studies
Arlington, VA
stead@seismo.css.gov
From: gary@ke4zv.uucp (Gary Coffman)
Subject: Re: Any info. on hydrogen power for cars??
Reply-To: gary@ke4zv.UUCP (Gary Coffman)
Organization: Gannett Technologies Group
Date: Wed, 18 Nov 1992 18:58:00 GMT

In article <1992Nov17.131916.12009@bsu-ucs> 00bndaniels@leo.bsuvc.bsu.edu writes:
>I would like to know if any US car company will make or research
>for a car that can run on hydrogen.  I only know of VW and BMW
>that are doing research on makinga car that can run on hydrogen
>I believe that hydrogen would be a great fuel for cars, and power 
>plants because the only by-product when it is burned is water.
>Any information on this topic is greatly appreciated.

Hydrogen is a tricky fuel to make work in an IC engine. Pre-ignition
is a severe problem. And of course the high chamber temperature and
pressure still generates oxides of nitrogen, only the HC emissions are 
eliminated. Current three way catalysts, to reduce the NOx, require HC 
to fuel them to the necessary high temperature. I suppose a fuel rich 
mixture of hydrogen could be used instead, but that could lead to a risk 
of cat converter explosions and cost mileage. The real problem, of course, 
remains tankage. It takes a lot of hydrogen to equal the energy content of 
a gallon of gasoline, and hydrogen is extremely low density at STP. Large 
very high pressure tankage, or large cryogenic tankage is required to 
replace the gasoline tank's energy capacity.

Using an external combustion engine (see discussion of steam power) would
eliminate most of the NOx and all of the pre-ignition problems, but wouldn't 
solve the tankage problem. Hydrogen is less dense than air. 

Gary


Newsgroups: sci.energy
From: sgs@grebyn.com (Stephen G. Smith)
Subject: Re: More External-Combustion Info
Organization: Agincourt Computing
Date: Thu, 19 Nov 1992 23:18:53 GMT

In article <1992Nov17.180135.25760@kakwa.ucs.ualberta.ca> sherwood@space.ualberta.ca (Sherwood Botsford) writes:

>3.  Given a closed system is there a better choice of working fluid than
>water (Something that wouldn't freeze, and could act as a lubricant.)

>=> Sherwood Botsford                   sherwood@space.ualberta.ca <= 

The reason for using water is its very high heat of vaporization --
roughly a measure of how much energy it takes to vaporize it.  The
higher the heat of vaporization, the less stuff you need in your engine
for a given power output.  Water is also cheap, nontoxic, nonflammable,
has halfway reasonable boiling and freezing points, and doesn't
decompose at high temperatures.

I seem to remember that there are a couple of CFCs that are almost as
good as water (Hey!  Put that down!  OUCH! :-) but not much else.

-- 
Steve Smith                     Agincourt Computing
sgs@grebyn.com                  (301) 681 7395
"Truth is stranger than fiction because fiction has to make sense."
Newsgroups: sci.energy
From: pngai@adobe.com (Phil Ngai)
Subject: Re: Electric car question.
Organization: Adobe Systems Incorporated
Date: Tue, 24 Nov 1992 01:53:35 GMT

In article <1992Nov23.210716.407@michael.apple.com> ems@michael.apple.com (E. Michael Smith) writes:
>>>How large would a properly packaged 10 kW SNAP generator be?
>
>(And maybe add a better vent to the garage roof to reduce the heat
>build-up in the garage...)

If you assume 10% efficiency (I suspect thermoelectric is very
low efficiency or it would be used in power plants) and 10 KW
out, you're talking about 90 KW of extra heat in your garage.
I suppose it could be dealt with but it sounds very dangerous
if the cooling system failed.

-- 
Will Intel be the only X86 chip maker without a 586?
From: carl@SOL1.GPS.CALTECH.EDU (Carl J Lydick)
Newsgroups: sci.energy
Subject: Re: opening of the first
Date: 15 Nov 1992 16:29:01 GMT
Organization: HST Wide Field/Planetary Camera
Distribution: world
Reply-To: carl@SOL1.GPS.CALTECH.EDU
NNTP-Posting-Host: sol1.gps.caltech.edu

In article <L27SBYL6@cc.swarthmore.edu>, dpeders1@cc.swarthmore.edu (Daniel Pedersen) writes:
=dietz@cs.rochester.edu (Paul Dietz) writes:
=> I would dispute your claim.  Triple paned glass windows are really
=> just conservation -- as long as you have a window, you want to make
=> the losses through it be low.  If anything, this *reduces* solar
=> heating, as the triple pane windows are somewhat less transparent that
=> double pane.
=
=I disagree.  Glass has a high transmission coefficient in the frequency
=range of the visible spectrum and the range of the spectrum at which the
=most enrgy is available in solar radiation.  However it has a small
=transmission coeff. in the thermal radiation range (IR).  What this means is
=that glass allows visible light to pass the energy in, but does not allow
=the themal energy to escape.  this is how greenhouses work.

Please, before the next time you repeat this piece of folklore, talk to someone
who actually knows something about greenhouses.  Or ask about it in
alt.folklore.science.
--------------------------------------------------------------------------------
Carl J Lydick | INTERnet: CARL@SOL1.GPS.CALTECH.EDU | NSI/HEPnet: SOL1::CARL

Disclaimer:  Hey, I understand VAXen and VMS.  That's what I get paid for.  My
understanding of astronomy is purely at the amateur level (or below).  So
unless what I'm saying is directly related to VAX/VMS, don't hold me or my
organization responsible for it.  If it IS related to VAX/VMS, you can try to
hold me responsible for it, but my organization had nothing to do with it.