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RE: Gas or Electric



As you and Bob pointed out, my terminology may be slightly in error. I am
referring to a mock up of a vehicle that I saw several years ago where the
fuel was water. You fill up the tank and the unit splits the water into
oxygen and hydrogen. Its not perpetual motion at all-you plug it into the
wall to get an initial charge of hydrogen which is collected into a
secondary tank. The hydrogen is then consumed in the fuel cell to creat
electricity to run electric motors which power the vehicle (suspect there
are other power transmission options to be considered also). Energy in
excess of what is instantaneously needed to power the vehicle charges
batteries, splits more water or both. At the end of the day, you fill the
water tank and plug the vehicle back into the power grid to create more
fuel for the next day's use.

The total amount of pollution created by this approach is almost entirely
dependent upon the source of the power going to the grid. Not sure how much
of this approach is being developed by the auto manufacturers, just know
that they believe fuel cells are the technology of the future.

I've not read anything about the applicability of fuel cell technology to
lawn mowers. If it can be made practical and economical enough to transport
people, it might some day replace grazing animals as well. The good news is
that the only by-product of a fuel cell is what you get when you combine
hydrogen and oxygen-water (could be some trace NOx, but probably minimal).

Sorry for the confusion. Hope this helps.

Warren

>yeah, warren -- I would be interested in what you meant here as well.
>There are
>schemes (including work at our own Lab over the past 6 or 7 years) to build
>integrated fuel cell/fuel reformer modules that work together, but generally a
>fuel cell is distinct from the fuel pre-processing operation.  The H2 is
>generated from hydrocarbons (natural gas or liquids) via steam reforming or
>similar process prior to entering the fuel cell.
>
>In many commercial applications (e.g., the H2 powered buses that Ballard has
>developed) H2 is in fact stored in modest quantities, rather than carry the
>weight of the additional processing equipment.
>
>I think OPEC is not particularly threatened by fuel cells, since they are
>merely
>a conversion device, not a source of energy.  Even with widespread
>adoption, the
>likelihood that they'll significantly impact global demand for oil is low.
>They'll simply allow more work to be done with the existing reserves, and
>(possibly/potentially) help to ease the transition to non-fossil sources like
>nuclear, direct solar, wind, etc (which can produce H2 via electrolysis at
>reasonably high efficiencies -- in the 80%+ range).
>
>SB
>
>> -----Original Message-----
>> From: Rudy Moehrbach [mailto:Rudy_Moehrbach@p2pays.org]
>> Sent: Friday, January 11, 2002 10:50 AM
>> To: 'Warren Weaver'; Rudy Moehrbach; p2tech@great-lakes.net
>> Subject: RE: Gas or Electric
>>
>>
>> Warren,
>> You state that the hydrogen is generated in the fuel cell.
>> Could you please
>> explain this to me. I seem to smell perpetual motion here.
>>
>> Rudy Moehrbach
>> Staff Engineer
>> Waste Reduction Resource Center
>> Phone 800-476-8686
>> Web http://wrrc.p2pays.org
>>
>>
>> -----Original Message-----
>> From: Warren Weaver [mailto:wjw5@psu.edu]
>> Sent: Friday, January 11, 2002 11:35 AM
>> To: Rudy Moehrbach; p2tech@great-lakes.net
>> Subject: RE: Gas or Electric
>>
>>
>> Well! This topic sure has generated a lot of interest!
>>
>> Note that the beauty of a fuel cell is that the hydrogen is
>> generated in
>> it, then immediately consumed to power the vehicle. This
>> avoids the need
>> for large quantities of hydrogen to be transported through
>> our cities and
>> suburbs. From my vantage point, fuel cells pose tremendous potential
>> advantages toward meeting our future energy needs. The big
>> question is can
>> the auto manufacturers make the technology affodable to the
>> average family?
>> If so, it will likely provide all of our transporation well
>> into the future
>> and will probably be adapted to meet our future heating needs
>> also. Fuel
>> cells will become pervasive. The bigger issue then will be
>> the impact on
>> the world economy. How will OPEC adapt? What will be the
>> politics of "big
>> oil"? What will fuel Middle Eastern economies "after oil"?
>> Note that Osama
>> bin Laden cited the fact that the Saudi princes are going
>> along oblivious
>> to the need to diversify their economies as one of the
>> reasons for sending
>> the world a wake up call on 9-11.
>>
>> Warren
>>
>> >The burning of the Hindenburg certainly should caution us all when
>> >considering the use of fuels to power engines. Imagine what
>> would happen if
>> >the general public were allowed to dispense a highly
>> explosive liquid fuel
>> >into their vehicle or a container at public places. The potential for
>> >spills, accidental or intentional, are tremendous. And the
>> tank trucks
>> >delivering this liquid fuel would have to travel on the same
>> roads as we
>> all
>> >do; when they crash we could lose whole city blocks. The
>> potential for
>> >catastrophe seems enormous. But his is how we have been
>> doing it for close
>> >to one hundred years with our gasoline fueled cars and
>> mowers. The problem
>> >has been managed. My two bits.
>> >
>> >Rudy Moehrbach
>> >Staff Engineer
>> >Waste Reduction Resource Center
>> >Phone 800-476-8686
>> >Web http://wrrc.p2pays.org
>> >
>> >
>> >-----Original Message-----
>> >From: Minicucci, Bob [mailto:rminicucci@des.state.nh.us]
>> >Sent: Friday, January 11, 2002 8:20 AM
>> >To: 'ryoder@mail.unomaha.edu'; p2tech@great-lakes.net
>> >Subject: RE: Gas or Electric
>> >
>> >
>> >At which point we must consider the manure management issue
>> for the 1500
>> >miniature horses required a 2000 home subdivision placed on
>> 500 acres of
>> >land.  The solution to this & the related sub-problems of stallion
>> >management are left for the student...
>> >
>> >No one in this discussion has mentioned the issue of why one
>> maintains
>> >'lawn' space.  For me, I maintain around 1 acre close-mowed
>> (in addition to
>> >about an acre meadow & the gardens), which is used for me & the kids
>> running
>> >around playing ball, shooting the fris, sledding, etc.  Many of these
>> >alternative ground cover suggestions cover the visual
>> aspects of 'lawn',
>> but
>> >it's hard to hit grounders on a rock garden ;)
>> >
>> >Additionally, I think the image of the burning Hindenburg is
>> an issue that
>> >needs to be considered if we want to build general public
>> acceptance of
>> >hydrogen as a fuel.
>> >
>> >TGIF,
>> >Bob Minicucci
>> >NH DES
>> >603-271-2941
>> >Illegitimati non carborundum
>> >
>> >-----Original Message-----
>> >From: ryoder@mail.unomaha.edu [mailto:ryoder@mail.unomaha.edu]
>> >Sent: Thursday, January 10, 2002 4:09 PM
>> >To: Brady, Bernard; p2tech@great-lakes.net
>> >Cc: 'hhaines@state.mt.us'; 'Estes, Laura'
>> >Subject: RE: Gas or Electric
>> >
>> >just a note on H2 production -
>> >
>> >one of the arguments against wind or solar power is that
>> power capacity
>> >isn't available when needed (still  or cloudy days) or is
>> available when it
>> >isn't needed.  i've oft considered hydrogen as an "energy
>> battery" in this
>> >case, allowing the overproduction to be stored in a portable
>> (but not yet
>> >universally usable.  Ahem,  at least until the fruition of the just
>> >announced Bush administration focus on fuel cell cars instead of more
>> >efficient fossil fuel vehicles) format.  Not my idea - it's
>> something a
>> >great shadetree mechanic, retired farmer type did just 15
>> miles from Iowa
>> >State University, where I got my engineering degree.  Quite
>> a guy - his old
>> >windmill would generate electricity that he's use to power
>> everything, but
>> >when his production exceeded demand, he'd split the water
>> into hydrogen and
>> >oxygen.  Ran his tractor on the H2, used teh gas for a
>> cutting torch and i
>> >can't remember what else. No rumor this - saw the local news
>> segment on it
>> >and it was a discussion in class the following day - back in
>> '81 or '82.
>> >pretty neat...  but not commercially viable, evidently -
>> which i always
>> >thought was the stress cracking issue of H2 reaction with
>> steel compounds -
>> >but with fiberwound composite tanks, that shouldn't be an
>> issue... must be
>> >something else.
>> >
>> >BTW - good point on the balance of what we like and what we
>> don't.  If we
>> >were thinking outside of the box, maybe we'd choose to
>> genetically engineer
>> >a horse or other grazing animal to fit in residential
>> neighborhoods.  Oh,
>> >wait!  It's been done - says here:
>> >http://www.amha.com/ that with supplemental (for a balanced diet, I
>> believe)
>> >feed, the pasture size requirement for a Miniature Horse is
>> 3 horses/acre,
>> >or that "one can easily be kept in the average residential backyard,
>> >depending upon local zoning laws"  Careful, those local
>> zoning folks can be
>> >real philistines.
>> >
>> >regards,
>> >
>> >ry
>> >
>> >********************************
>> >Richard Yoder, PE
>> >Director, P2ric.org
>> >1313 Farnam St.   Ste. 230
>> >Omaha, NE  68182
>> >
>> >402-595-2381
>> >fax: 402-595-2385
>> >ryoder@unomaha.edu
>> >http://www.p2ric.org
>> >http://nbdc.unomaha.edu
>> >
>> >
>> >
>> >
>> >
>> >                    "Brady, Bernard"
>> >
>> >                    <bbra461@ECY.WA.GO        To:
>> "'Estes, Laura'"
>> ><laurae@montana.edu>, "'P2Tech@great-lakes.net'"
>> >                    V>
>> <P2Tech@great-lakes.net>
>> >
>> >                    Sent by:                  cc:
>> >"'hhaines@state.mt.us'" <hhaines@state.mt.us>
>> >                    owner-p2tech@great        Subject:     RE: Gas or
>> >Electric
>> >                    -lakes.net
>> >
>> >
>> >
>> >
>> >
>> >                    01/10/02 12:20 PM
>> >
>> >                    Please respond to
>> >
>> >                    "Brady, Bernard"
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >It's always interesting to see that in these discussions, we
>> attempt to
>> >support the alternative we like by leaving out or
>> overlooking some of its
>> >negatives while loading up the alternative we don't like with all the
>> >imaginable negatives. I agree with Howard Haines' points
>> about the real
>> >justifications for preferring electric mowers (cord or cordless) over
>> >gasoline-powered being geographically specific. Outside LA,
>> maybe, this is
>> >a
>> >tempest in a teapot. However, there are a couple of Howard's
>> comments that
>> >need correction. One is that gas turbine power plants are
>> not more energy
>> >efficient than thermal plants ... BTW: I assume he means
>> coal-fired plants.
>> >Gas turbine, coal-fired, and nuke all get electricity by
>> converting from
>> >heat. If typical coal-fired efficiency is 33 to 35% (Howard's Montana
>> >example), they're a lot less efficient than a gas-fired
>> turbine at 52 to
>> >60%
>> >... I assume we're both talking about the ratio of the power
>> output to fuel
>> >heat value. And as for emissions, Howard suggested looking
>> at the back end
>> >of jet engines (for those who don't know it, gas turbines
>> are jet engines
>> >bolted down). That ain't fair. Gas turbines in power plants are now
>> >required
>> >to have selective catalytic and carbon monoxide catalyst
>> control systems
>> >that reduce NOx and CO (and some VOC) emissions to small
>> fractions of what
>> >comes out the back end of an uncontrolled jet engine.
>> >
>> >The second comment is that fuel cells are 80% efficient.
>> That's only true
>> >for the conversion of hydrogen heat value to power output.
>> Unfortunately,
>> >there ain't no uncombined hydrogen around. Natural gas and
>> coal are used in
>> >a form not greatly different from the way they come out of
>> the ground.
>> >Gasoline is distilled from petroleum along with some
>> reforming reactions to
>> >break too big molecules down to gasoline range. Some energy
>> value is lost
>> >in
>> >that process. But, you can only get hydrogen with a net
>> energy value by
>> >reforming it from a fossil fuel. So, you really start with
>> something like
>> >gasoline before you get to the fuel cell. Yes, you can get hydrogen
>> >electrolytically from water, but you get no net heating
>> value. You have to
>> >use just as much energy (actually more) to separate hydrogen
>> from oxygen as
>> >you'd bet back by re-combining it at the fuel cell. Anyway,
>> when you reform
>> >the fossil fuel, say methane (the simplest), you lose the
>> heat value of the
>> >carbon part of the molecule. If I remember correctly, the
>> net efficiency of
>> >a reformer - fuel cell combo is about 50%. On the other hand, at the
>> >emissions source, the emissions are only water and carbon dioxide.
>> >
>> >Not that I expect anyone will really have read this far, but
>> I finally have
>> >a compulsion to offer my "what to do" suggestion: Keep using your
>> >gas-powered mower 'til it wears out. Then replace it with
>> whatever is most
>> >cost effective and useful for you. Take care of it. Service
>> it: Change the
>> >oil, clean the filter, clean and/or replace the spark plug, drain and
>> >dispose of the gas in the tank at the end of the mowing
>> season. Set the
>> >mower for the highest grass length. Cut the grass frequently
>> enough to keep
>> >your neighbors happy, but don't try for Better Homes and
>> Gardens awards.
>> >Water enough in the summer to keep the whole lawn from
>> turning brown, but
>> >not so much that your yard looks like a field of emerald
>> green. Kill the
>> >lawn weeds: By hand if you have time, or spot spray. Replace
>> your lawn with
>> >a vegetable or flower garden if you like. But, that'll be a
>> lot more work
>> >than the lawn, so be realistic. Don't worry. Be happy.
>> >
>> >-----Original Message-----
>> >From: Estes, Laura [mailto:laurae@montana.edu]
>> >Sent: Thursday, January 10, 2002 9:30 AM
>> >To: 'P2Tech@great-lakes.net'
>> >Cc: 'hhaines@state.mt.us'
>> >Subject: FW: Gas or Electric
>> >
>> >
>> >This information from a colleague who has done quite a bit of engine
>> >emissions work.
>> >
>> >-----Original Message-----
>> >From: Haines, Howard [mailto:hhaines@state.mt.us]
>> >Sent: Wednesday, January 09, 2002 4:28 PM
>> >To: 'Estes, Laura'; Tomas Vinson (E-mail)
>> >Subject: RE: Gas or Electric
>> >
>> >
>> >Dear Laura and Tomas,
>> >
>> >I am not on the P2Tech, but you can post it there. This
>> reads like someone
>> >should have shown up at one of my workshops with the Health
>> and Air Quality
>> >Impacts of Bio-based Fuels and Lubes in Small Engines slide
>> show. These
>> >were
>> >given in Montana, Minnesota (2), Michigan (7), New York,
>> Washington D. C.,
>> >and are now being done in parts of Canada.
>> >
>> >As of January 2002, the newer lawnmowers would be the most efficient
>> >mechanical units in terms of energy, CO2 emissions, and
>> reduced pollution
>> >for areas that do not have air quality problems.
>> >
>> >Newer lawnmowers are almost all 4-stroke engines (see the
>> EPA report at
>> >OTAQ), and some have electronic fuel injection-quite a bit
>> cleaner than
>> >older 2-strokes, and more energy efficient (less CO2
>> emissions).  For data,
>> >look at a number of reports by CARB and Southwest Research Institute.
>> >
>> >In most of the data I have seen, the reasoning behind
>> electric lawn mowers
>> >(and vehicles) is to move the pollution out of an air shed
>> that has poor
>> >air
>> >(exceeding regulated pollutant levels), and away from
>> people, to an air
>> >shed
>> >where the electricity is produced.  The idea is to reduce
>> pollution at the
>> >site of use so that other pollution sources (like industries
>> that have
>> >fewer
>> >energy options) can operate in the same air shed.  In most
>> cases when you
>> >think about it, electric mowers don't make much sense except for the
>> >utility
>> >companies.  True, a coal-steam plant in Montana may be 33 to
>> 35 percent
>> >efficient, but it looses (rule of thumb) about ten percent
>> to move it down
>> >to California.  With that size of operation, the typical battery and
>> >recharge losses (30 to 45 percent) would cut the efficiency
>> or increases
>> >the
>> >emissions even more.  From an energy or emissions
>> standpoint, an electric
>> >lawn mower is like cutting butter with a chainsaw.
>> >
>> >Gas turbines for electric production are not all that
>> efficient compared to
>> >the large thermal plants, but they are cheap.  As for
>> emissions, just look
>> >out the back of any turbojet airplane and see the difference.
>> >
>> >Fuel cells where the heat can be used can get up to 85
>> percent efficiency,
>> >but they are just now starting to come down in price. If you
>> don't think a
>> >fuel cell-powered mower is possible, then I won't worry you
>> with the one I
>> >saw at a unit of the Department of Defense in Utah.  They
>> also have a fuel
>> >cell-powered utility vehicle (bigger than a golf cart,
>> smaller than an
>> >auto)
>> >that has an overall efficiency of somewhere in the mid-40s.
>> There are
>> >plans
>> >for a fuel cell-powered snowmobile as well, but that is
>> still on paper for
>> >the time being.
>> >
>> >For a specific comparison of fuel economy, CO, HC, and PM
>> emissions between
>> >2- and 4- stroke small engines, see the fourth, sixth, and
>> seventh slides
>> >(titled Emissions of 2-stroke vs 2-stroke Engines) in the
>> Health and Air
>> >Quality Impacts of Bio-based Fuels and Lubes in Small
>> Engines slide show
>> >(at
>> >http://www.deq.state.mt.us/CleanSnowmobile/montana/hpp.pdf ).  In the
>> >fourth
>> >slide, a comparison of CO and HC is done for two 2-stroke snowmobile
>> >engines
>> >circa 1995 and 1998, a 1998 personal water craft engine, a
>> 4-stroke engine
>> >is a utility-type engine (a bit bigger, but not unlike a
>> lawn mower), and
>> >an
>> >advanced 4-stroke engine (with emission controls similar to
>> an automotive
>> >engine).  The sixth slide down compares fuel consumption,
>> and the seventh
>> >illustrates particulate matter emissions.  The data were all
>> developed at
>> >Southwest Research Institute, some of which was paid for by this
>> >Department.
>> >
>> >Information on cleaning up these small engines also on the web site
>> >(www.deq.state.mt.us\cleansnowmobile or
>> www.cleansnowmobilefacts.org .
>> >Just
>> >by using an ethanol blend fuel and low emissions lube oil in
>> a two-stroke
>> >engine, we measured reductions of CO by 9 to 38 percent, HC
>> reductions of
>> >16
>> >to 27 percent, and particulate matter reductions of 25 to 70
>> percent.  NOx
>> >was not affected, and NOx emissions from 2-stroke engines
>> are low-so low
>> >that they produce ammonia.  A number of colleges have also
>> been looking
>> >into
>> >cleaning up and quieting down 2-stroke engines as illustrated in the
>> >results
>> >from the SAE Clean Snowmobile Challenge (also on the web
>> site).  Catalytic
>> >converts are available and used (in Europe, Asia, and some
>> places here) for
>> >engines as small as chain saws.  It would not be a problem
>> to put one on a
>> >lawn mower.
>> >
>> >I suspect many on the P2Tech list will not have to worry
>> about snowmobile
>> >emissions, but the same principles apply to jet skis,
>> personal watercraft,
>> >small marine engines, and ATVs.  This site represents over
>> $1 million in
>> >research done in or for the greater Yellowstone (as in National Park)
>> >region.
>> >
>> >Back to the first topic of keeping the area around buildings
>> trimmed in a
>> >acceptable (pollution-prevention) method.
>> >
>> >I would suggest a more efficient way to keep the grass
>> short-use a drought
>> >resistant grass variety (like buffalo grass) and/or your
>> neighbors' horses
>> >(or sheep) to periodically mow it.  I also limit watering.
>> If I don't
>> >water, I don't have to mow here in Montana. I keep it dry
>> enough to where
>> >dandelions don't grow, but it stays green to keep the dust
>> down. I know
>> >that
>> >some places in this country it rains (Seattle, WA, Beaumont
>> TX, New Jersey,
>> >New York, Michigan), so other methods might be needed.  Like
>> possibly not
>> >growing any grass at all: put in a vegetable garden with mulch, or do
>> >something a bit more natural.
>> >
>> >This was less than 15 minutes of thought/typing, and I
>> apologize if it was
>> >boring.  Just know that someone has been working on the
>> problem of 2-stroke
>> >engine emissions because once you are out the U. S., almost all the
>> >vehicles
>> >use either diesel or 2-stroke engines.
>> >
>> >Howard Haines
>> >Bioenergy Engineering Specialist
>> >Montana Department of Environmental Quality
>> >Hhaines@state.mt.us
>>
>>
>>