Subsequent Discussion: Electric Car Efficiency vs. Gasoline

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johnkarls
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Joined: Fri Jun 29, 2007 8:43 pm

Subsequent Discussion: Electric Car Efficiency vs. Gasoline

Post by johnkarls »

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---------------------------- Original Message ----------------------------
Subject: Re: More on Electric-Motor Efficiency vs. Gasoline-Motor Efficiency
From: John Karls
Date: Wed, November 25, 2009 7:29 am
To: Dr. June Taylor, Ted Gurney, Tom Chancellor
--------------------------------------------------------------------------

Dear June, Ted & Tom,

Thank you all for your comments with regard to the topic for our last meeting.

The reason for writing is to provide a “heads up” that it strikes me as appropriate to post our comments so far on our bulletin board (http://www.ReadingLiberally-SaltLake.org) so that our other members will be apprised of where the discussion stands and will be in a position to provide further comments if they wish. To summarize –

1. Tom raised the point at our meeting that electric vehicles are more efficient than gasoline-engine vehicles, partially offsetting the 400% more greenhouse gases and 700% more sulfuric acid (think “acid rain”) produced “all in” by the electric vehicles because all new electric-generating plants for the last 30 years have used (and for at least the next 5 years or so will use) coal or, in a few cases, other hydrocarbons such as natural gas or fuel oil and 75% of the coal (or other hydrocarbons) is expended in the electric-generation process.

2. Although it would appear that the U.S. Department of Energy has removed all relevant data on comparative efficiency from its web sites, there are two lengthy Wikipedia articles that appear below that address the issue and that appear to be well researched.

3. The articles indicate that for city driving only, the efficiency of electric vehicles “all in” (including the electric-generation impact) is comparable to the AVERAGE U.S. automobile. This means –

3-a. For city driving only, an electric vehicle “all in” produces the same amount of greenhouse gases as the AVERAGE U.S. automobile.

3-b. Nevertheless, even for city driving, an electric vehicle “all in” produces 175% of the amount of sulfuric acid (think “acid rain”) as the AVERAGE U.S. automobile.

3-c. For highway driving, an electric vehicle “all in” is a disaster from a greenhouse-gas viewpoint as well as an “acid rain” viewpoint.

3-d. For a conservation-minded consumer, the choice of a Chevrolet Volt or a Toyota Prius is a “no brainer” – the U.S. Department of Energy’s new “Fuel Economy Guide” which was just released for the 2010 models (http://www.fueleconomy.gov/feg/FEG2010.pdf) indicates that the Toyota Prius is rated at 51 miles/gallon for city driving.

3-e. This means the Toyota Prius is 2.55 times more efficient for city driving than the average U.S. car – compared to which the Chevrolet Volt is only comparable “all in” with respect to greenhouse-gas emissions and generates 175% as much sulfuric acid (think “acid rain”).

3-f. In other words, the Chevrolet Volt “all in” generates 255% as much greenhouse gases as the Toyota Prius and 450% as much sulfuric acid (think “acid rain”) as the Toyota Prius.

*****
It should be noted –

1. We are ignoring the even-greater environmental disaster that is the Chevrolet Volt if it is used for highway driving, or if it is used for city driving beyond the 40-mile range of its batteries.

2. We are ignoring the fact that electric motors are already nearly 100% efficient while the efficiency of gasoline engines could be doubled by simply requiring the same mileage (“CAFE") standards in the U.S. that both American and foreign car companies satisfy in Europe.

3. A small item = since electric motors are already nearly 100% efficient, they have no heaters (the inefficiency of a gasoline engine is primarily waste heat which can be used to power a heater for the car interior)!!! If a Chevrolet Volt is used in conditions that require using a heater, it cannot even compete with the AVERAGE U.S. automobile even in its limited niche of solely city driving within its 40-mile battery range and when solely measured by greenhouse-gas emissions (and given a “free pass” on “acid rain”).

Your friend,

John K.


---------------------------- Original Message ----------------------------
Subject: More on Electric-Motor Efficiency vs. Gasoline-Motor Efficiency
From: John Karls
Date: Tue, November 24, 2009 9:13 am
To: Dr. June Taylor
Cc: Ted Gurney; Tom Chancellor
--------------------------------------------------------------------------

Dear June,

Thank you very much for your information about natural gas.

Just to show you I have not been idle, there was about a 60-minute window
available last evening to investigate further – so I spent it entirely on
Tom Chancellor’s point about electricity motors being more efficient than
gasoline motors.

As previously mentioned, there seems to be a dearth of information about
this issue and what little there is from authoritative sources seems is
horribly dated – for example, DOE’s http://www.fueleconomy.gov (which I don’t
even recall contains even a useful generalization) speaks about the FUTURE
2003 goal of the California fuel cell partnership!!!

However, there are a few nuggets (this must be what “panning for gold” was
like!!!) that have appeared so far in various articles of presumably
varying quality. Indeed, I am embarrassed to admit that the only
seemingly-worthwhile nuggets so far have come from Wikipedia whose
accuracy is often questioned. But c’est la vie!!! Here are the two
nuggets for what they are worth –

**********
Excerpt from a Wikipedia Article on “Engine Efficiency”
(en.wikipedia.org/wiki/Engine_efficiency)

Gasoline (petrol) Engines

Modern gasoline engines have an average efficiency of about 25% to 30%
when used to power a car. In other words, of the total heat energy of
gasoline, 70 to 75% is ejected (as heat from the exhaust) as mechanical
sound energy or consumed by the motor (friction, air turbulence, heat
through the cylinder walls or cylinder head, and work used to turn engine
equipment and appliances such as water and oil pumps and electrical
generator), and only about 25% of energy moves the vehicle. At idle the
efficiency is zero since no usable work is being drawn from the engine. At
slow speed (i.e. low power output) the efficiency is much lower than
average, due to a larger percentage of the available heat being absorbed
by the metal parts of the engine, instead of being used to perform useful
work. Gasoline engines also suffer efficiency losses at low speeds from
the high turbulence and head loss when the incoming air must fight its way
around the nearly-closed throttle; diesel engines do not suffer this loss
because the incoming air is not throttled. Engine efficiency improves
considerably at open road speeds; it peaks in most applications at around
75% of rated engine power, which is also the range of greatest engine
torque (e.g. in the 2007 Ford Focus, maximum torque of 133 foot-pounds is
obtained at 4,500 RPM, and maximum engine power of 136 brake horsepower
(101 kW) is obtained at 6,000 RPM).

Diesel Engines

Engines using the Diesel cycle are usually more efficient, although the
Diesel cycle itself is less efficient at equal compression ratios. Since
diesel engines use much higher compression ratios (the heat of compression
is used to ignite the slow-burning diesel fuel), that higher ratio more
than compensates for the lower intrinsic cycle efficiency, and allows the
diesel engine to be more efficient. The most efficient type, direct
injection Diesels, are able to reach an efficiency of about 40% in the
engine speed range of idle to about 1,800 rpm. Beyond this speed,
efficiency begins to decline due to air pumping losses within the engine.

Compression Ratio

The efficiency depends on several factors, one of which is the compression
ratio. Most gasoline engines have a ratio of 10:1 (premium fuel) or 8:1
(regular fuel), with some high performance engines reaching a ratio of
12:1 with special fuels. The greater the ratio the more efficient is the
machine. Higher ratio engines need gasoline with higher octane value,
which inhibits the fuel's tendency to burn poo nearly instantaneously
(known as detonation or knock) at high compression/high heat conditions.

It should be noted that at lower power outputs, the effective compression
ratio is less than when the engine is operating at full power, due to the
simple fact that the incoming fuel-air mixture is being restricted. Thus
the effective engine efficiency will be less than when the engine is
producing its maximum rated power. One solution to this fact is to shift
the load in a multi-cylinder engine from some of the cylinders (by
deactivating them) to the remaining cylinders so that they may operate
under higher individual loads and with correspondingly higher effective
compression ratios. This technique is known as variable displacement.

Diesel engines have a compression ratio between 14:1 to 25:1. In this case
the general rule does not apply because Diesels with compression ratios
over 20:1 are indirect injection diesels. These use a prechamber to make
possible high RPM operation as is required in automobiles and light
trucks. The thermal and gas dynamic losses from the prechamber result in
direct injection Diesels (despite their lower compression ratio) being
more efficient. An engine has many parts that produce friction. Some of
these friction forces remain constant (as long as applied load is
constant); some of these friction losses increase as engine speed
increases, such as piston side forces and connecting bearing forces (due
to increased inertia forces from the oscillating piston). A few friction
forces decrease at higher speed, such as the friction force on the cam's
lobes used to operate the inlet and outlet valves (the valves' inertia at
high speed tends to pull the cam follower away from the cam lobe). Along
with friction forces, an operating engine has pumping losses, which is the
work required to move air into and out of the cylinders. This pumping loss
is minimal at low speed, but increases approximately as the square of the
speed, until at rated power an engine is using about 20% of total power
production to overcome friction and pumping losses.

A gasoline motor burns a mix of gasoline and air, consisting of a range of
about twelve to eighteen parts (by weight) of air to one part of fuel (by
weight). A mixture with a 14.7:1 air/fuel ratio is said to be
stoichiometric, that is when burned, 100% of the fuel and the oxygen are
consumed. Mixtures with slightly less fuel, called lean burn are more
efficient, whilst slightly rich mixtures, with lower air fuel ratios
produce more power at the expense of higher fuel consumption. The
combustion is a reaction which uses the air's oxygen content to combine
with the fuel, which is a mixture of several hydrocarbons, resulting in
water vapor, carbon dioxide, and sometimes carbon monoxide and
partially-burned hydrocarbons. In addition, at high temperatures the air's
oxygen tends to combine with the air's nitrogen, forming oxides of
nitrogen (usually referred to as NOx, since the number of oxygen atoms in
the compound can vary, thus the "X" subscript). This mixture, along with
the unused nitrogen and other trace atmospheric elements, is what we see
in the exhaust.

Oxygen

The air is approximately 21% oxygen; if there is not enough oxygen for
proper combustion, the fuel will not burn completely and will produce less
energy. An excessive rich air fuel ratio will cause an increase of
pollutants from the engine. The fuel burns in three stages. First, the
hydrogen burns to form water vapour. Second, the carbon burns to carbon
monoxide. Lastly, the carbon monoxide burns to carbon dioxide. This last
stage produces most of the power of the engine. If all of the oxygen is
consumed before this stage because there is too much fuel, engine's power
is reduced.

There are a few exceptions where introducing fuel upstream of the
combustion chamber can cool down the incoming air through evaporative
cooling. The extra fuel that is not burned in the combustion chamber cools
down the intake air resulting in more power. With direct injection this
effect is not as dramatic but it can cool down the combustion chamber
enough to reduce certain pollutants such as nitrous oxides, while raising
others such as partially-decomposed hydrocarbons.

The air-fuel mix is drawn into an engine because downward motion of the
pistons induces a partial vacuum. A compressor can be used to force a
larger charge into the cylinder to produce more power. In practice this is
achieved either by belt driven supercharging or exhaust driven
turbocharging. Also, two-stroke diesel engines have forced induction,
where a supercharger moves air into the engine or the crankcase so that
the cylinder will be filled with air as soon as the inlet port is
uncovered.

There are other methods to increase the amount of oxygen available inside
the engine; one of them, is to inject nitrous oxide, (nitrous) to the
mixture, and some special engines use nitromethane, a fuel that provides
the oxygen itself it needs to burn. Because of that, the mixture could be
1 part of fuel and 3 parts of air; thus, it is possible to burn more fuel
inside the engine, and get higher power outputs.

Steam

Piston steam engines are relatively inefficient (about 8% overall
efficiency) which is why there are no longer any steam locomotives in
commercial use. Large output steam turbines equal or exceed the efficiency
of the Diesel, which is one reason they are used for electric utility
generating plants (the other reason is the greatly reduced maintenance
requirement). The Stirling cycle engine has the highest efficiency of any
thermal engine but it is more expensive to make and is not competitive
with other types for normal commercial use.

The gas turbine is most efficient at maximum power output. Efficiency
declines steadily with reduced power output and is very poor in the low
power range. This is one reason, among several, why the gas turbine is not
used for automobiles and trucks where much of the operating cycle is at
idle and low to intermediate speeds. Detroit (General Motors) at one time
tried to make a gas turbine for an automobile and gave up. This is also
why gas turbines can be used for peak power electric plants. In this
application they are only run at full power where they are efficient or
shut down when not needed.

**********
Excerpt from a Wikipedia Article on “Electric Car”
(en.wikipedia.org/wiki/Electric_car)

Energy efficiency

Proponents of electric cars usually tout an increased efficiency as the
primary advantage of an electric vehicle as compared to one powered by an
internal combustion engine. The energy efficiency comparison is difficult
to make because the two vehicles operate on different principles. Vehicles
powered by internal combustion engines operate convert energy stored in
fossil fuels to mechanical energy through the use of a heat engine. Heat
engines operate with very low efficiencies because heat cannot be
converted directly into mechanical energy. Electric vehicles convert
stored electric potential into mechanical energy. Electricity can be
converted into mechanical energy at very high efficiencies. A quick
analysis will show electric vehicles are significantly more efficient.

However, electricity (in a form usable for humans) does not naturally
exist in nature. The electricity used for electric cars may be created by
converting fossil fuels to electricity using a heat engine (with a similar
efficiency as an automotive engine), converting nuclear energy to
electricity using a heat engine, or through dams, windmills, or solar
energy. Each of these conversion processes operate with less than 100%
efficiency and those involving heat engines operate at relatively low
efficiencies.

When comparing the efficiencies of an electric vehicle to a gasoline
vehicle, the efficiency of the source of generating the electric energy
must be included in the comparison. For example, it would be incorrect to
say that an electric vehicle charged each night from a gasoline powered
generator is more efficient than a gasoline powered vehicle.

An electric car's efficiency is affected by its charging and discharging
efficiencies, which ranges from 70% to 85%. The electricity generating
system in the US loses 9.5% of the power transmitted between the power
station and the socket, and the power stations are 33% efficient in
turning the calorific value of fuel at the power station to electrical
power.[10] Overall this results in an efficiency of 20% to 25% from fuel
into the power station, to power into the motor of the grid-charged EV,
comparable or slightly better than the average 20% efficiency of
gasoline-powered vehicles in urban driving, though worse than the about 45
% of modern Diesel engines running under optimal conditions (e.g. on
motorways).

Production and conversion electric cars typically use 10 to 23 kW·h/100 km
(0.17 to 0.37 kW·h/mi).[7][11] Approximately 20% of this power consumption
is due to inefficiencies in charging the batteries. Tesla Motors indicates
that the vehicle efficiency (including charging inefficiencies) of their
lithium-ion battery powered vehicle is 12.7 kW·h/100 km (0.21 kW·h/mi) and
the well-to-wheels efficiency (assuming the electricity is generated from
natural gas) is 24.4 kW·h/100 km (0.39 kW·h/mi).[12] The US fleet average
of 10 l/100 km (24 mpg-US) of gasoline is equivalent to 96 kW·h/100 km
(1.58 kW·h/mi), and the Honda Insight uses 32 kW·h/100 km (0.52 kW·h/mi)
(assuming 9.6 kW·h per liter of gasoline).

The greater efficiency of electric vehicles is primarily because most
energy in a gasoline-powered vehicle is released as waste heat. With an
engine getting only 20% thermal efficiency, a gasoline-powered vehicle
using 96 kW·h/100 km of energy is only using 19.2 kW·h/100 km for motion.

The waste heat generated by an ICE is frequently put to beneficial use by
heating the vehicle interior. Electric vehicles generate very little waste
heat and electric heaters must be used to heat the interior of the
vehicle. Electric vehicles used in cold weather will show increased energy
consumption and decreased range on a single charge.

**********
Observations While Standing on a “Mossy Rock”

Of note in passing, Ted, the fourth paragraph of the second article speaks
to your question about whether the bulk of the 75% loss in energy content
vis-à-vis electricity that I have been using comes from losses in
transmission. I gave you a quick answer while jumping into the shower
Saturday afternoon that the bulk of the loss occurs in generation and not
transmission – while observing that it should be quicker to “chase that
rabbit” on DOE’s web site than our own bulletin board (if memory serves,
DOE was the source of the confirming data when my similar assertions were
questioned two years ago, but I would have to search quite a bit to find
where the results were posted on our bulletin board).

The fourth paragraph asserts that electrical utilities are only 33%
efficient in converting their fuel to electricity (67% generation loss is
the bulk of the 75% loss I have been citing) and goes on to say that in
the U.S. we lose “9.5% between the power station and the socket.”
However, if I were trying to answer your question, I would look for better
sources, starting with DOE’s web site. I am only noting that a non-“Gold
Standard” source supports both the 75% loss number I have been using and
my quick answer Saturday about the bulk of that 75% occuring in generation
vs. transmission.

Back on message.

An interesting bias of the author(s) of the second Wikipedia article is
that s/he-they compare the “20% to 25% from fuel into the power station,
to power into the motor of the grid-charged EV” to an “average 20%
efficiency of gasoline-powered vehicles in urban driving.”

Several problems.

The excerpt from the first Wikipedia article starts with: “Modern gasoline
engines have an average efficiency of about 25% to 30% when used to power
a car.” In all fairness, the author(s) of the second article are only
claiming that the electric car is barely competitive for urban driving
(while tacitly admitting that it is not even “in the ball park” for
highway driving).

Another problem is one we discussed at length at our Nov 18th meeting –-
Congress’ abysmal record on CAFE standards. Merely requiring cars
marketed in America to meet European CAFE standards rather than American
CAFE standards (which in broad outline would only mean retooling American
plants producing engines – which isn’t that difficult says a UAW member
who spent the summer of 1964 operating three drill presses on the skeleton
mid-night > 8:00 a.m. (“grave yard”) shift of a General Motors assembly line
building up stock behind the faster machines -– and should be done, anway,
regardless of difficulty), the comparison for solely-urban driving wouldn’t
even be close.

Another problem is that virtually all American electric-generation plants
constructed during the last 30 years are coal-fired, and coal spews into
the atmosphere on average not only 400% of the greenhouse gases but also
700% times sulfuric acid (think “acid rain”) as an equivalent amount
energy-content-wise as gasoline.

So even if electric cars were outlawed on highways, and only permitted on
urban streets until Congress acquires enough back bone to raise CAFE
standards, they would still produce 175% (700%/400%) of the sulfuric acid
that gasoline-engine cars produce in urban driving.

And I believe all of us on this e-mail are old enough to have learned at
Woodstock that “acid rain” travels hundreds if not thousands of miles!!!

An overall observtion.

Even if we believe that Congress will never increase CAFE standards so
that electric vehicles are barely competitive FOR URBAN DRIVING ONLY
vis-à-vis greenhouse gases (while still “out of the ball park” vis-à-vis
“acid rain”) – THEN WHY SHOULDN’T THE U.S. GOVERNMENT’S GENERAL MOTORS
SUBSIDIARY BE CHAMPIONING A NEW G.M. HYBRID COMPARABLE TO THE PRIUS, WHICH
CAN “LEAVE IN THE DUST” A PLUG-IN ELECTRIC VEHICLE EVEN IN ITS NICHE
SPECIALITY OF GREENHOUSE GASES FROM URBAN DRIVING???

So there we have it. Voilà.

At least for the time being. Though if another time window opens, I may
chase these rabbits a bit further. And, in any event, would be very
interested in the results if any of you have time.

Incidentally, we have had occasion to discuss censorship on the web (and
how amusing it is to re-confirm published information that is still on
microfiche in libraries around the country even though it has been removed
from the web).

In this regard, I would hate to think that the U.S. government has removed
all of the information for which we have been searching, particularly from
its DOE site, in order to support the public’s misperception that electric
vehicles are green.

Your friend,

John K.


---------------------------- Original Message ----------------------------
Subject: Re: [Fwd: Re: Re: Reading-Liberally]
From: Dr. June Taylor
Date: Mon, November 23, 2009 10:14 pm
To: John Karls
Cc: Ted Gurney
--------------------------------------------------------------------------

>John said to Ted:
*>So two questions for you -- (1) is methane simply called "natural gas" in
the sense that it is a flammable gas that is "natural" or is >methane what
is actually produced from a primary-drive oil well???

*John, I can answer (1) with some confidence: yes, "natural gas" means
methane (CH4). As you pointed out last meeting, the gas issuing from the
ground is processed (to remove acidic oxides of S & N, and also to remove
higher molecular-weight hydrocarbons like ethane, propane, etc), including
that from primary-drive oil wells. This site
http://www.naturalgas.org/overview/background.asp gives the composition of
"natural gas" - as you will see, it's *mostly *methane.

"Natural gas is a combustible mixture of hydrocarbon gases. While natural
gas is formed primarily of methane, it can also include ethane, propane,
butane and pentane. The composition of natural gas can vary widely, but
below is a chart outlining the typical makeup of natural gas before it is
refined.
*Typical Composition of Natural Gas* Methane CH4 70-90% Ethane C2H6 0-20%
Propane C3H8 Butane C4H10 Carbon Dioxide CO2 0-8% Oxygen O2 0-0.2%
Nitrogen N2 0-5% Hydrogen sulphide H2S 0-5% Rare gases A, He, Ne, Xe
traceAs
piped into residences & industrial users, it's essentially all methane.
Also, biogas obtained from fermentation ( planned or fortuitous (cow farts))
is at least as much methane as the table above shows. So we can take
"natural gas" from oil wells, natural gas wells, or farts or anaerobic
fermentation as ~ methane.

June


---------------------------- Original Message ----------------------------
Subject: Fwd: Re: Reading-Liberally
From: John Karls
Date: Mon, November 23, 2009 3:16 am
To: Dr. June Taylor
Cc: Ted Chancellor
--------------------------------------------------------------------------

Dear June,

Thank you very much for your e-mail of yesterday afternoon.

It is a shame that I misunderstood your point about up-grading the
nation's power grid coming immediately after my attempt to forge agreement
that we should favor either worldwide oil price guarantees for investors
in wind or solar projects and/or the U.S. government assuming this risk
itself by undertaking such projects directly in a TVA-style program.

At least I am glad to know, going forward, that both you and I agree on this.

Incidentally, I would like to thank you very much for your efforts to
improve attendance. As I was googling various items in connection with my
e-mail to attendees of our meeting last Wednesday about "Issues Left
Hanging," I encountered several notices of our meeting that you had posted
in various places on the web.

*****
TED'S E-MAIL

I was looking for you during the Coffee Hour yesterday because I was
interested in whether you had any insight regarding the questions that I
put to Ted in the following e-mail.

This relates to an "issue left hanging" that was raised during our meeting
by Tom Chancellor. You might recall his point that he was under the
impression that electric motors are more efficient vis-a-vis power in/out
than gasoline motors and, if so, this would partially offset the 75% loss
of energy content of the original fuel that is used in producing
electricity.

Incidentally, the reasons why I did not address this point in my "Issues
Left Hanging" e-mail are (1) Tom only indicated that his impression, if
true, would only partially offset the 75% energy loss so it would have no
impact on my proposed conclusion that all plug-in electric vehicles should
be banned until all electric-utilities using carbon fuels are replaced,
and (2) I couldn't, as described in my e-mail to Ted, find anything on
Tom's point.

Also incidentally and worthy of note in passing, this is the kind of point
which, though excellent, I always hope will be raised before a meeting via
the bulletin board (or by e-mail) so that, if the correspondence develops
into something of interest to the general membership, it can be posted on
the bulletin board. From my perspective of trying to reach worthwhile
conclusions at our meetings (and, possibly, six-degrees-of-separation
e-mail campaign recommendations), it's frustrating for points that are
surprising (at least for me) to be raised in a meeting when it is no
longer possible to investigate whether they are true.

But back "on message."

After hitting "send" on my e-mail to Ted, an answer to one of the
questions put to Ted seemed to have an obvious answer.

If in these various oxidation equations regarding carbon fuels, either CO
or CO2 is being produced in addition to H2O, it stikes me that both carbon
atoms and hydrogen atoms are being oxidized. And, accordingly, energy is
being produced by both types of oxidation. Though I would have no idea
how much energy is produced from oxidizing a cabon atom as compared to
oxidizing hydrogen.

That's not "moving the ball down the field" very much. But hopefully it
doesn't comprise "being thrown for a loss"!!!

If you have any insights and/or sources, they would be appreciated.

Your friend,

John K.

---------------------------- Original Message ----------------------------
Subject: Re: Reading-Liberally
From: John Karls
Date: Sat, November 21, 2009 2:52 pm
To: Ted Gurney
--------------------------------------------------------------------------

Dear Ted,

Thank you for both of your e-mails. I'm glad you will be able to attend
the December meeting. And yes, you had provided a "heads up" that you
would miss October & November due to piano lessons.

The 75% energy loss figure was "a given" when I was doing substantial
fund-raising for UNEP at the request of the Under-Secretary General for
the Environment. Someone challenged that figure about two years ago and I
dug out some data, from the DOE web site if memory serves, and posted it
on the bulletin board. At this point, it would probably be quicker to get
current DOE figures rather than search the Bulletin Board -- but I have to
shower and shave in order to meet friends downtown (25 minutes travel for
me) for dinner at 5:00 pm followed by a show.

My recollection is that virtually all of the 75% was consumed in the
conversion process itself (vs. in the transmission). And my memory should
be fairly good on this because that is one of the issues that was raised
two years ago.

Incidentally, I agree with you that a "plug in" electric car makes sense
if it is NOT being powered by the existing grid. Though my impression is
that electricity from solar panels is converted to AC in order to power
appliances around the home -- though perhaps ("dumb old me") they are
solely DC and used for heating. Either way, it would be a shame if we
could not make an exception for electricity coming from wind or solar.
But I am guessing that fashioning a law that would sort out who is
plugging into the grid and who is using wind/solar would be too "Big
Brother"-ish.

Your chemistry is very intriguing. And at the same time very humbling --
for example, I do not even know whether burning (oxidizing) a molecule
containing both carbon atoms and hydrogen atoms produces its power from
oxidizing the hydrogen or from some combination!!!

However, I am skeptical about your claim that natural gas is primarily
methane. Yes, there are a lot of jokes on late-night shows about farm
animal flatulence. But virtually all natural gas is produced from oil &
gas wells and, I would have thought from 13 years working in the oil
patch, that the associated natural gas would, sans impurities, have the
same chemical composition as the crude oil.

In this regard, I don't particularly care about your chemical formulas for
gasoline and resid, since the percentage of carbon vs. hydrogen in both
formulas is comparable. However, I'm sure you know that a conventional
oil refinery is nothing more than a big "moonshine still" with various
petroleum products (starting with kerosine/avjet) boiling off at various
temperatures until you are left with "resid" (i.e., residual fuel oil aka
diesel) and finally asphalt (which should have been called "resid" but the
term was coined for fuel oil in the days before anyone figured out a
commercial use for the asphalt).

So two questions for you -- (1) is methane simply called "natural gas" in
the sense that it is a flammable gas that is "natural" or is methane what
is actually produced from a primary-drive oil well??? and (2) does the
amount of power generated by oxidizing a hydrocarbon come solely from the
number of hydrogen atoms in the fuel and does the number of hydrogen atoms
per volume vary with the fuel??? (I assume the answer to the second part
of the second question is yes to some extent, because I would assume avjet
is more powerful per unit of volume than diesel, though I don't actually
know that as a fact.)

One more thing. I have been searching the internet for information about
energy input/output for electric motors and for gasoline motors. Because
someone suggested that even though 75% of the energy content of
the original fuel is expended in the conversion to electricity, electric
motors are more efficient I/O-wise than gasoline motors thereby somewhat
reducing the disaster of electric motors whose electricity comes from
coal-fired electric plants. Do you know of any credible sources on energy
I/O of various types of motors??? (I tried DOE and a few other likely
sources that would be credible, but couldn't find anything.)

Again, thank you for writing. I hope you have time to provide some
feedback. If not, I'll look forward to seeing you in December.

Your friend,

John K.



---------------------------- Original Message ----------------------------
Subject: Reading-Liberally
From: Ted Gurney
Date: Sat, November 21, 2009 12:04 pm
To: John Karls
--------------------------------------------------------------------------

I have a question about the electric car. Where did you get the figure of
300-400% energy loss? Is it mainly from transmission line losses? If so, a
solution to the problem could be local power generation by wind or solar,
going "off the grid". There are some affordable products on the market now
which can do just that. So the electric car could be practical right away.


The next best thing is the NGV, the natural gas fueled vehicle. Natural
gas is chiefly methane, CH4, while gasoline is chiefly octane, C8H18, and
diesel is chiefly decane, C10H22. Natural gas engines do produce CO2 but
less of it per horsepower than do gasoline or diesel engines. Also natural
gas can all be produced domestically while the other two require imported
oil.


Ted

Ted Gurney
Site Admin
Posts: 14
Joined: Sun Aug 16, 2009 8:41 pm

Re: Subsequent Discussion: Electric Car Efficiency vs. Gasoline

Post by Ted Gurney »

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---------------------------- Original Message ----------------------------
Subject: Re: More on Electric-Motor Efficiency vs. Gasoline-Motor Efficiency
From: Ted Gurney
Date: Wed, November 25, 2009 12:30 pm
To: John Karls
Cc: Dr. June Taylor; Tom Chancellor
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Dear everybody,

I keep thinking of the no-driving alternative in this discussion. Sell your car! Or at least sell down to one car per family. You will be richer in more ways than one.

For the last 20 years I have been trying to avoid driving a car and ride a bike or take public transportation instead. It does involve compromises and frequently transportation takes twice as long as driving but there are benefits such as exercise, extra reading time, and feelings of moral superiority. So I just plan the extra transportation time into my schedule and try to read on the bus.

I have to admit I have not been able to sell my transportation philosophy to the rest of my family. They are hopelessly car-addicted. (I suspect you are too, but maybe not, I can always hope.) But at least we have only one car. I think one compact car of any kind beats two Priuses.

This morning I handed out leaflets at the turkey giveaway. Our leaflet, composed by Crossroads Urban Center, asked people to call Gov. Herbert asking him to veto a bill he will get in the coming session which doubles the sales tax on groceries. (Utah is one of only 13 states that taxes unprepared food. It is the most regressive possible tax.) The Indian Cultural Center right next to the Trax station near the baseball park every year the day before Thanksgiving gives away several hundred turkeys to poor people. The line went around the block before 9:00 AM, the hour when the giveaway started. I fear that this year there were more people than turkeys. The point in this discussion is that the poor people getting in line for free turkeys arrived at the giveaway in CARS, big luxurious, gas-guzzling ones.

When I was teaching I once had a student apologize to me for being late to class because it took so long to park his car. "Why drive at all?", I asked. "Our University provides you with a free bus pass". "Ride the bus?", he responded. "Are you kidding? The bus is for losers!" Well, there you have it. The car is part of our cultural ego. It is going to be a tough fight.

I hope gas goes to $5 a gallon. If that does not work, try $7, then $8.... Money will conquer the ego problem eventually.

Ted

UtahOwl
Site Admin
Posts: 82
Joined: Mon Jul 28, 2008 10:48 pm

Re: Subsequent Discussion: Electric Car Efficiency vs. Gasoline

Post by UtahOwl »

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---------------------------- Original Message ----------------------------
Subject: Re: More on Electric-Motor Efficiency vs. Gasoline-Motor Efficiency
From: Dr. June Taylor
Date: Wed, November 25, 2009 4:51 pm
To: John Karls
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Dear John

Your summary is very good.

It would have been much better for America if the Powers-That-Were in the past 10 years hadn't stood foursquare against
ANY improvement in CAFE standards. BTW, it is my impression that the Europeans make their CAFE standards by (1) using more efficient diesel engines. [The problem with diesels is that they do produce significantly more nasty unburned particles (P10 etc) - Denise probably has figures on this.] and (2) making their vehicles smaller, which instantly ups the mileage. Anyone who owns an efficient car more than 10 yrs old (like my '91 Camry) has probably noticed that the 2008 models have much lower MPG - because they are bigger & heavier than 10 yrs ago.

My point: the Europeans didn't improve the efficiency of the standard gasoline engine to get better mileage - they downsized their vehicles and in many cases went to diesel engines.

June

solutions
Site Admin
Posts: 232
Joined: Fri Jul 13, 2007 8:38 pm

Re: Subsequent Discussion: Electric Car Efficiency vs. Gasoline

Post by solutions »

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From: Solutions
To: Tom Chancellor; Ted Gurney; John Karls; June Taylor
Sent: Thu, November 26, 2009 10:43:57 AM
Subject: Re: More on Electric-Motor Efficiency vs. Gasoline-Motor Efficiency

Dear Friends,

Perhaps it is time I “weighed in” on something, since the discussion is so interesting.

June Taylor’s e-mail of yesterday sparked two thoughts.

First, if it is true (June only claims that it is her “impression”) that European CAFE standards have been met by using diesel engines and “making their vehicles smaller” then an interesting comparison relating to “making their vehicles smaller” would be comparing the size of the Chevrolet Volt with the Toyota Prius.

However, the Chevrolet Volt is still a concept – it is not scheduled to begin production until Nov 2010, which probably explains why its official web site (http://www.gm-volt.com) does NOT list its weight!!!

Nevertheless, the Chevrolet Volt is classified by General Motors as a “compact” while the Toyota Prius is classified in the US Department of Energy’s 2010 Fuel Economy Guide as “midsize.” So there is already an “apples and oranges” factor in favor of the Chevrolet Volt.

The second thought?

Tom Chancellor’s basic point was that electric motors are almost perfectly efficient while the inefficiency of gasoline engines can partially offset the 75% inefficiency of electric-utility plants as they convert coal and other hydrocarbons to electricity.

As we have seen in the discussion so far, virtually all of the inefficiency of gasoline engines comprises waste heat.

Putting aside June’s impression about how Europeans have met increased CAFE standards with smaller vehicles, it strikes me that what is happening with the NON-“PLUG IN” hybrids such as the Prius is that the waste heat of the gasoline engine is being converted ON BOARD THE VEHICLE to electricity that can then be used to help power the vehicle.

Accordingly, one of John’s points (that the Chevrolet Volt “all in” has no hope of improvement unless all of the nation’s coal-fired and other hydrocarbon-fired electric utilities are replaced completely by clean electric-generation sources = wind/solar/nuclear) is true.

While one of John’s contrasting points (that gasoline engines have considerable room for improvement) is being demonstrated by the NON-“PLUG IN” hybrids which put the inefficiency of the gasoline engine (waste heat) to use as on-board-generated electricity that can be used to propel the vehicle.

A recommendation!

American CAFE standards should not only be increased drastically – but, more importantly, they should be broken down to VERY SMALL vehicle-size categories (or perhaps even made formulaic to preclude “gaming”).

If this is done, the standards could be designed so that they not only encourage smaller, lighter vehicles, but so that they also encourage if not compel on-board-electricity-generation to harness the waste heat of the gasoline engine.

Best regards,

Solutions

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