HDTenEightyP/NetNews huggingface dataset:
From: gary@ke4zv.uucp (Gary Coffman)
Newsgroups: sci.energy
Subject: Re: Electric Cars Energy Usage: Summary  NEW DATA
Date: 13 Apr 92 16:54:17 GMT
Reply-To: gary@ke4zv.UUCP (Gary Coffman)
Organization: Gannett Technologies Group

In article <sntj30+@lynx.unm.edu> cn0gr8af@hydra.unm.edu (Student Class Account) writes:
>
>First of all, I would like to thank Gary for the work he has done in
>calculating energy usage for electric vehicles.  It is obvious that he 
>is trying to elucidate what is often misunderstood.

Thank you for the kind words. A nit to pick however.

>One other thought I might add concerns comparisons between horsepower
>of electric and gasoline powered vehicles.  The horsepower rating of an
>electric motor is usually flat (or linearly decreasing, depending on how
>the motor is wound, starting at its maximum rating) throughout its entire
>RPM range.  That is, the maximum rated horsepower is available from a dead
>start.  This is not the case for a piston engine (unless there is a lot of
>slipping at the engine-clutch interface during take-off).  

Power=Torque*RPM

Horsepower of any engine at zero RPM is zero. What you should have said
was that for certain types of electric motors, *torque* is maximum at
zero RPM and is flat or decreasing at higher RPM. This makes transmissionless
electric vehicles practical. Peak horsepower occurs at the point on the
curve where torque starts decreasing faster than RPM increases.

BTW, sounds like a nice little car you've built. Would you consider
doing some timed acceleration runs and posting the numbers?

Gary
From: ems@Apple.COM (Mike Smith)
Newsgroups: sci.energy
Subject: Re: Conservation (was Re: Green Coal (:-) (was Re: Victor ...)
Date: 8 Apr 92 19:34:48 GMT
Organization: Apple Computer Inc., Cupertino, CA

In article <1992Apr3.192253.20458@cs.rochester.edu> dietz@cs.rochester.edu (Paul Dietz) writes:
>In article <64750@apple.Apple.COM> ems@Apple.COM (Mike Smith) writes:
>
>>>>My 'fridge is an old GE.  It sucks an average of 800W/hr.

>>>Come again?

>>I put an Watt-Hour meter on it. 

>>I read the meter in the morning, the afternoon, and at night.  Both
>>the period to period and the start of test to end of test averages
>>for watt-hours consumption were noted.  The test was run for 3 days.
>>(19.2 kWhr/day divided by 24 hr/day = .8kW or 800 W instantanious).

>>That is, the total Watt-Hours was divided by total Hours to give
>>average Watts:  Whr/hr=W.  This is a scalar quantity.  Watts.
>>To turn this back into a vector, we add time back in by saying that
>>800 Watts instantanious for one hour would be 800 Watts/hour.

>Whoa.  800 watts times 1 hour is 800 watt-hours, NOT 800 watts/hour.
>Watts/hour is a measure of the rate of change of power (i.e., the
>second derivative of energy).
>
>The clear way of saying this is "the time-averaged power use of
>the refrigerator is 800 W".

I think I've figured out why my phrasing confused the issue.  The
correct math/physics phrasing would be that it consumed 800Whr/hr.
The correct verbal phrasing would be that it consumed an average of 
800W over time.

I mixed the two symbologies and got "an average of 800W/hr" (which most 
folks read as 800 watts per hour, dropping the 'average') and which I
was reading as "an average of 800 watts over a typical time"

I'm sorry to have confused the issue by mixing math and verbal symbols;
I think it comes from having a lack of dominant brain hemisphere 
(ambidextrous, identical PSAT and SAT scores (to the exact digit!),
IQ scores within a trivial variation, no constant eye dominance, etc..)
To me it made perfect sense to equate the phrasings:
average 800W over time
average 800W / time
average 800W / hr
even though the last one has a predefined and conflicting meaning.
(I had a temp of 101 at the time of the posting, but doubt that that
 was the defining issue... I'm better now, and 'average 800W / time'
 still makes sense with the / read as 'over'...)

I know, we use a common language and phrasings have to conform to the
expected norms or it will just confound the issue.  Yet there is still
room for regional dialect and personal accent.  Sorry to have stepped
over the line from personal accent and into confounding sludge.  (But
it has been enlightening... I hadn't realized before that I sometimes
read / as 'over' ...)

>Yes, that is one inefficient piece of junk.

It is now sitting on the patio.  The new fridge is in.  PG&E bills
delta will be posted in a month or two.

-- 

E. Michael Smith  ...!sun!apple!ems

'If you can dream it, you can do it'  Walt Disney

This is the obligatory disclaimer of everything. (Including but
not limited to: typos, spelling, diction, logic, and nuclear war)
Newsgroups: sci.energy
Subject: The effect of charging current spikes on Pb/H+ Batteries 
From: mathiega@elec.canterbury.ac.nz (G. A. Mathieson)
Date: 10 Apr 92 16:20:45 +1200
Distribution: world
Organization: Electrical Engineering, University of Canterbury, New Zealand
Keywords: Solar Power, Efficient Charging System

I am designing a DC-DC converter that is required to interface solar cells to an Electric Vehicle battery (Lead-Acid - 300V nominal bus voltage), such that the efficiency is maximised. Though a good day's sunshine is unlikely to provide more than 10% of 30kW.hr full charge, even the smallest gain in efficiency may be useful in less power-hungry applications.

The high-frequency (~1E5Hz) converter that will probably be used will have voltage spikes with comparable or higher frequency content. Since another consideration is power-conversion density, I am keen to minimise the size/weight of the output filters.

Is there anyone out there who knows what sort of effect these spikes have on batteries that are supposedly suited to constant current charging, with a final taper? Information directly related to converter and output filter characteristics, such as the effective load (battery) impedance at varying levels of charge would be very useful.

				Electric Vehicles for EVer (100 years anyway)
			Grant Mathieson (mathiega@elec.canterbury.ac.nz)
From: wreck@fmsrl7.srl.ford.com (R. Cage)
Subject: Re: Continuously Variable Transmissions
Summary: Some reality
Organization: Ford Motor Company Scientific Research Labs, Dearborn, MI
Date: Fri, 10 Apr 1992 21:47:05 GMT

In article <1992Apr10.205852.13845@mlb.semi.harris.com> jws@cica4.mlb.semi.harris.com (James W. Swonger) writes:
>In article <1992Apr9.213013.19678@fmsrl7.srl.ford.com> wreck@fmsrl7.srl.ford.com (R. Cage) writes:
>>....  A CVT requires too much power to be
>>controlled using electric actuators alone, and the belt
>>clamping pressure is supplied by a hydraulic pump.
>
> Seems like to me a hydraulic actuator is pretty wasteful of energy; a 
>worm drive from an electric motor would hold position with no power 
>input.

The problem is that peak shifting power requirements can be
measured in horsepower, at least in vehicular applications.
If you can't shift fast enough, you can't react to demand
and nobody is going to buy a vehicle with your transmission...
That's a bit much for electric systems suitable for production
in automobiles; other applications may differ.

The issue I don't see electric drives addressing is clamping
pressure.  If you under-clamp the belt, it slips and destroys
things in short order.  (I've seen the results; a $10,000
experimental pulley turns into a paperweight in seconds.)
Hydraulics let you put equal clamping pressure over the whole
system very easily; worm drives don't lend themselves to such
simple methods.

Geared automatic transmissions, with their clutches and bands,
have much smaller hydraulic requirements than CVT's.

>I think one thing that hangs people up is the idea that these
>transmissions -must- be infinitely variable, when you could probably get
>by with a large but finite number of speeds and a lockup torque converter
>or something like that. Let the donut soak up the bumps from indexing between
>ratios. 

This is fine except that gear sets are neither free, weightless
nor minuscule.  A 9-speed transmission will do a good job of
simulating a CVT in fuel economy, but where would you put 9
planetary gearsets under the hood of a car, how much fuel would
it take to lug them around, and what would they cost?

Letting the torque converter damp the shift transients sounds
like a good idea until you realize that you lose a lot of fuel
that way (the more often you shift, the more fuel you lose).

Above a certain number of gears, CVT's are clear winners.
-- 
Russ Cage              wreck@fmsrl7.srl.ford.com  russ%rsi@sharkey.cc.umich.edu
  *  When Ford pays me for my opinions, THEN they can call them theirs. *

                           _Bad_ cop.  No donut.
Newsgroups: sci.energy
From: kudzu@tfs.com (Michael Sierchio)
Subject: Re: Internal Combustion Engines
Organization: TRW Financial Systems
Date: Thu, 16 Apr 1992 01:30:10 GMT

In article <1992Apr15.232226.23903@menudo.uh.edu> 
	kevin@taronga.taronga.com (Kevin Brown) writes:

>In article <1992Apr15.170303.10462@fmsrl7.srl.ford.com> 
>	wreck@fmsrl7.srl.ford.com (R. Cage) writes:
>>Summary:  Hydrogen makes a lousy fuel for an internal combustion engine.
>
>So how well does it do in a gas turbine engine?

Huh? That's an internal combustion engine, too.

-- 
Michael Sierchio                               TRW Financial Systems
kudzu@tfs.com                                     1947 Center Street
                                             Berkeley, CA 94704-1105
(MKS2)                                                  510.704.3380
From: gary@ke4zv.uucp (Gary Coffman)
Newsgroups: sci.energy
Subject: Re: Electric vs. gas cars
Date: 15 Apr 92 18:46:50 GMT
Reply-To: gary@ke4zv.UUCP (Gary Coffman)
Organization: Gannett Technologies Group

In article <1992Apr14.181450.14151@oakhill.sps.mot.com> dong@oakhill.sps.mot.com (Don M. Gibson) writes:
>FYI:  i did a back-of-the-envelope calculation and, if we just cover the
>roofs of 70 million homes with solar cells, we could supply all the
>electrical energy the US consumes.  I haven't heard anything about those
>low cost TI cells in a long time--what's the deal.  [assumptions: 8 hours
>of sun for 200 days, 1000 sf of roof and 20% efficiency].

Yeah. There are only a few flies in the ointment. First cost per installed
watt is from 2 to 10 times current rates depending on whose data you use.
Second, the grid has to be totally restructured to handle the power. See
my notes on chaotic grids under the windpower thread. Third, it takes a
lot of power to manufacture solar cells. (yeah I hear the cries of "boot-
strap", but that's slow.) Fourth, storage. The sun doesn't shine at night.

Assuming that we are willing to internalize the environmental costs of
fossil power, and that's a big assumption ripe with politics. See my
comments on Public Service Commissions and structural rates. We can
show that solar is cost effective if we can internalize the environmental
costs, but we are still faced with an enormous capital cost to actually
implement the plan. Ditto restructuring the grid. If solar can be made
actually *cheaper* than fossil without internalizing the environmental
costs, then it will have a much better chance of being implemented.
That requires 7 cent per kWh installed cost. Since cell designs are
approaching theoretical maximum efficiencies, the cost cutting is going
to have to occur in *manufacturing* the cells. There are some promising
process technologies for thin film cells that may eventually do this.

Storage is a nasty problem. Batteries aren't generally good enough or
environmentally friendly enough for the task. Pumped hydro storage is
promising, but there are limited sites and it has environmental costs
as well. Pumped air storage looks better, flywheels hold promise, and
electrolyzing water and using fuel cells is efficient but costly.

None of the approaches is as cheap as simply keeping on keeping on, and
letting the fossils burn. Getting those environmental costs internalized
is the tough problem.

Gary
Newsgroups: sci.energy
From: evan@gauss.math.brown.edu (Evan M. Simpson)
Subject: Mixed power sources for electric cars
Organization: Brown University Math Department
Date: Thu, 16 Apr 1992 20:54:21 GMT

   I realize that this topic is somewhat off the charter for sci.energy, but I'm posting
here because of the rash of electric car discussion here.

   I have little to no technical knowledge on the issues involved, but in my casual reading
on the subject of electric cars I've gathered the following ideas:

1) If battery limitations are ignored, it is perfectly possible to build an electric motor-
driven vehicle with performance (accel, top speed, etc.) stats at least as good as standard
gas powered models. Motors with high, flat torque response eliminate the need for any kind
of transmission.

2) Again ignoring where we get the power, we can thus build a full size, non-fragile, fully-
powered car with a simple drive train, and regenerative braking (possibly supplemented by 
mechanical braking for full stops) which is run on electricity.

3) Fuel burning turbines able to run at constant speed and power draw can be much more 
efficient than a motor that is powering a vehicle, thanks to the vastly simpler requirements
they must meet. A generator burning gas/alcohol/methane/etc. could be made smaller and
easier to maintain than a car engine.

4) Battery and control system electronics are currently adequate for the tasks of buffering
the output from a generator and feeding it to a motor, and holding the power regenerated in 
braking.

If any or all of these points are mistaken, please tell me, preferably in simple terms.

   To the point: If the above are correct, couldn't one build an automobile run by electric
motors, powered by a fuel-burning turbine under the hood? The turbine assembly could be made
to be easily replaced, so that a changeover to a new fuel, or even to high-capacity future
batteries, could be a simple matter.

Evan Simpson
evan@gauss.math.brown.edu
Brown Unversity Math Department
From: kevin@taronga.taronga.com (Kevin Brown)
Subject: Re: Internal Combustion Engines
Reply-To: kevin@taronga.taronga.com (Kevin Brown)
Organization: Minimal.
Date: Wed, 15 Apr 1992 23:22:26 GMT

In article <1992Apr15.170303.10462@fmsrl7.srl.ford.com> wreck@fmsrl7.srl.ford.com (R. Cage) writes:
>Summary:  Hydrogen makes a lousy fuel for an internal combustion engine.

So how well does it do in a gas turbine engine?

>Russ Cage              wreck@fmsrl7.srl.ford.com  russ%rsi@sharkey.cc.umich.edu


		Kevin Brown (kevin@taronga.taronga.com)
From: goo0002@cuphub.cup.edu
Newsgroups: sci.energy
Subject: SOLAR ENERGY --UTILIZATION
Date: 15 Apr 92 14:39:40 GMT
Organization: California University of Pennsylvania, California, PA



		HELP NEEDED URGENTLY


	I am writting a paper on the utilization of solar energy
what i need now is an estimate on the cost of solar panels . this is to
support a community of about 2000. the location is in the West Indies 
thus there should be no lack of actual sunlight


  	any help from anyone will be accepted with my deepest thanks
From: 01crmeyer@bsu-ucs.uucp
Newsgroups: sci.energy
Subject: Off-shore wind power: ideas & discussion
Date: 15 Apr 92 00:47:38 GMT
Article-I.D.: bsu-ucs.1992Apr14.194738.6393

I'd like to investigate the practicality of an evolution of the Darrius Wind 
Turbine, customized for off-shore use, where there's an abundance of wind and 
space.

Would any of you like to help/participate/advise/discuss this?

CM  01crmeyer@leo.bsuvc.bsu.edu
From: gary@ke4zv.uucp (Gary Coffman)
Newsgroups: sci.energy
Subject: Re: Internal Combustion Engines
Date: 17 Apr 92 15:14:12 GMT
Reply-To: gary@ke4zv.UUCP (Gary Coffman)
Organization: Gannett Technologies Group

In article <1992Apr15.223236.16722@grace.dsir.govt.nz> srgxbhh@grace.dsir.govt.nz writes:
>In article <1992Apr12.183213.13212@eskimo.celestial.com>, nanook@eskimo.celestial.com (Robert Dinse) writes:
> 
>>      I can't see of any way to make an internal combustion engine that uses
>> air as the oxidizer not have this problem.  You can reduce the problem by
>> using lower temperatures and pressures, but you get lower thermo-dynamic
>> effeciency.  This is one of the reason gas milage went to hell around '74
>> when compression ratios were lowered in the name of meeting NOx emission
>> requirements.
>
>One of the reasons?. I suspect that the reduced CR wasn't only for meeting NOx
>emission requirements, as there were techniques available to reduce tailpipe
>NOx emissions. I can't comment on the US requirements at that time, nor the
>reasons why the CR was lowered rather than improving combustion etc..  

The auto companies were looking for a quick fix to meet the new emissions
requirements. Changing pistons required the least retooling and development.
Later, as the standards gradually tightened, and the companies gained
confidence in the new catalyst technologies that allowed very thin films
of expensive precious metals to be used, NOx as well as HC became catalyst
controlled. By that time, however, the use of lead in gasoline had become
restricted. Therefore the auto companies were forced to keep the low
compression ratios that harm power and efficiency because high enough
octane fuel was no longer regularly available, and would have poisoned
the catalysts anyway.

[useful storage comparison deleted]

>>      One thing that reduces knocking, reduces NOx emissions and improves
>> effeciency is water injection.
>
>Interesting.... My notes from reading about hydrogen include the following
>"The power output is comparable, however water injection ( to reduce NOx )
> lowers power and efficiency. All NOx would be eliminated by the use of O2"
>Unfortunately I don't have the citation, but if water is so wonderful, why
>not forget the hydrogen completely and run the engine on water. :-)

The usual way of getting water into the chambers in a hydrogen engine
is to use exhaust gas recirculation. The exhaust product is mostly
water vapor. Coupled with a fuel rich pre-chamber, a hydrogen engine
can be made to run cleanly and smoothly. Power density in current 
designs is poor however, due to poor storage capability and the
low reaction energy of the fuel/air mixture. You just can't cram
as much hydrogen in a normally aspirated engine as you can gasoline.
Supercharging brings back NOx and detonation problems.

External combustion Stirling cycle engines get around these problems,
except for storage density. Hydrogen can easily be made to burn clean in
a steady flame.

Gary
Newsgroups: sci.energy
From: jws@cica4.mlb.semi.harris.com (James W. Swonger)
Subject: Re: Continuously Variable Transmissions
Date: Sat, 11 Apr 1992 22:54:21 GMT
Organization: Harris Semiconductor, Melbourne FL

 What I had in mind as a discrete-step transmission was not a set of
planetaries, but something more like a variant of the CVT. However, instead
of a metal belt transmitting power by friction (hence requiring controlled
clamping force on the cones) I envisioned a cogged flat belt, where the
cogs index up/down in number as the pulley diameter is indexed. A sparse
tooth cog could have a reasonable range. The apparent diameter would have
to index such that the cog tooth spacing changed integrally. This sort
of arrangement would require no clamping force, although a tensioner arm
such as external serpentine belts employ would probably be necessary. 
--
##########################################################################
#Irresponsible rantings of the author alone. Any resemblance to persons  #
#living or dead then yer bummin. May cause drowsiness. Alcohol may inten-#
#sify this effect. Pay no attention to the man behind the curtain. Billy!#
From: Environmental Studies School <ssu@igc.org>
Newsgroups: sci.energy
Date: 08 Apr 92 09:51 PDT
Subject: Re: Continuously Variable Transmissions
Nf-ID: #R:1992Apr6.162730.4547@csc.canterb:-2018140026:cdp:1466300056:000:1131
Nf-From: cdp.UUCP!ssu    Apr  8 09:51:00 1992


	I am not familiar with IVTs or EpiLogic but am familiar with the 
operation of CVTs. Subaru sells the Justy 3-cylinder econocar with a CVT
automatic here in the US. However, this is merely an electronically controlled
version adapted from motor scooters. It is controlled by electronic signals
rather than the oil pressure (in the trans.). It only changes ratios, not gears,
there are no gears. A belt connects 2 pulleys, 1 input, 1 output. The pulleys
squeeze the belt and effectively change diameter, thus changing ratios. The
big problem: this system doesn't yet work with high torque systems, including
high horsepower cars. I too have contemplated its use with electric cars, but
I am uncertain about possible outcome/results. The current idea (see Popular
Science) with variable speed wind generators is to change blade angle like 
some airplanes do with their propellers. This does seem to work and broadens
the range of operating speeds for these units. However, wind turbines must
still be shut down at high speeds and probably still would not turn at less
than 5-6mph wind speed. Hope this helps.
		- Matt Karber, SSU
i

Xref: sparky sci.energy:2483 sci.misc:1041
Organization: University of Illinois at Chicago
Date: Friday, 10 Apr 1992 11:22:57 CDT
From: <U58603@uicvm.uic.edu>
Newsgroups: sci.energy,sci.misc
Subject: Science teaching

 The Chicago Academy of Sciences, a museum and educational
institution seeks information and resources available by the
Internet or otherwise for help in improving two of its programs:

Environmental Issues Forum (EIF) and Science Teaching Network
(STN).

EIF is a series of courses for Chicago Public School teachers on
ecological principles and global environmental problems and
issues.  The four courses--Air Quality Issues, Water Quality
Issues, Land Use Issues, and Solid Waste and Recycling--correlate
with the Academy outreach program, Ecological Citizenship, (Eco*Cit)
for grades  K-8 on environmental issues.

STN is a series of week-long workshops for Chicago Public School
teachers on four science topics--Hands-on Biology, Hands-on
Physical Science, Hands-on Chemical Science, and Hands-on Earth
Science--that correlate with the Academy outreach program,
Science on the Go, (SOG) for grades K-8.

The two programs are designed to produce better science teachers
by showing teachers how they can approach various science topics
in exciting, imaginative ways.  They use everyday, inexpensive,
easy to find items for the experiments.  The teachers don't sit
back and watch demonstrations--they get involved and do the
experiments themselves.

The CAS Education Department would be interested in the following:
What kind of research is being done with teachers--
  to change their attitudes toward teaching science?
  to enhance their abilities to teach science?

What kind of research is being done on outreach programs like
Eco-Cit and SOG?
  What are the ingredients for successful outreach programs?
  How many contacts of outreach educator with school work best?
  Who determines the curriculum?
  How are teachers encouraged to buy in?

What research is being done about Urban Environmental Education?
  What works?
  What are the needs of the audience?
  What programs exist now?

Any and all comments from interested persons and institutions
would be helpful.
Please respond to: U58603@UICVM.UIC.EDU
Thank you !
C. Dunn  Technical Operations Manager
The Chicago Academy of Sciences
2001 N. Clark St.
Chicago, IL 60614
(312) 549-0606
Newsgroups: sci.energy