## Re: C02: cycling vs. driving

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• Let s take up the challenge concerning cycling vs. driving as to which produces more C02 with a back-of-the-envelope calculation. The trick is to make rough
Message 1 of 15 , Oct 26 11:21 AM
Let's take up the challenge concerning cycling vs. driving
as to which produces more C02 with a back-of-the-envelope
calculation. The trick is to make rough approximations that
are at least within an order of magnitude of the correct result.
Thus, for example, if a liter is 1.057 quarts, we can round this
to 1, as it won't affect the order of magnitude of the results.
Then, we can make firm conclusions about quantities that differ
by one or more orders of magnitude, as the difference can't be
accounted for by mere error in approximations of the basic inputs.
Here goes:

Let's make some generous assumptions. First off, we'll assume
we're using among the most fuel efficient cars on the market,
say a Geo Metro, getting some 50mi/gal. We'll assume that the
fully loaded Geo Metro with four passengers still gets the same
mileage. How much carbon is each occupant responsible for per
mile? Gasoline consists of a variety of hydrocarbons, like benzene,
for example. Each passenger is responsible for 1/200 gal per mile.
I think gasoline is heavier than water, but assuming it's at least
no lighter than water, with specific gravity 1, then 1/200 gal of
gasoline = (1/200)(~4 liter)(1000cc/liter)(1g/cc) = 20g gasoline.
Taking benzene (C6H6) as a typical constituent hydrocarbon, that
comes out to ((6x12)/(6x12+6x1)) x 20 g = 18.46 g of carbon available
for conversion to C02 in combustion, for which each passenger is
responsible.

Now, the cyclist. I can go at least a hundred miles on a thousand
calories of food, from personal experience. That's 10kcal/mi. Food
is broken down into glucose (C6H12O6), to produce energy. Refined
sugar is converted almost completely to such simple sugars, and
according to the USDA nutrient database (www.nal.usda.gov), it
provides 3.89 kcal/g. So, I need
((10kcal/mi)/(3.89kcal/g))x(6x12/(6x12+12x1+6x16)) = 1.028 g/mi
carbon.

That's nearly twenty times more carbon for a carpooler in the efficient
vehicle than for the cyclist. Even assuming electric vehicles, which
get the equivalent of some 150 mi/gal in energy consumption, the
cyclist doesn't even come close to the auto passenger in carbon
utilization.

Guy
• An interesting argument. BTW water is heavier then gas. ... _________________________________________________________________________ Get Your Private, Free
Message 2 of 15 , Oct 26 12:10 PM
An interesting argument. BTW water is heavier then gas.

>From: Guy Berliner <guy@...>
>>I think gasoline is heavier than water, but assuming it's at least
>no lighter than water, with specific gravity 1, then 1/200 gal of

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• You need to subtract from the carbon generated by the cyclist the amount he would have spent anyway just sitting in a car. ... From: Guy Berliner
Message 3 of 15 , Oct 26 12:40 PM
You need to subtract from the carbon generated by the cyclist the amount he
would have spent anyway just sitting in a car.

-----Original Message-----
From: Guy Berliner [mailto:guy@...]
Sent: Thursday, October 26, 2000 11:21 AM
To: carfree_cities@egroups.com
Subject: [carfree_cities] Re: C02: cycling vs. driving

Let's take up the challenge concerning cycling vs. driving
as to which produces more C02 with a back-of-the-envelope
calculation. The trick is to make rough approximations that
are at least within an order of magnitude of the correct result.
Thus, for example, if a liter is 1.057 quarts, we can round this
to 1, as it won't affect the order of magnitude of the results.
Then, we can make firm conclusions about quantities that differ
by one or more orders of magnitude, as the difference can't be
accounted for by mere error in approximations of the basic inputs.
Here goes:

Let's make some generous assumptions. First off, we'll assume
we're using among the most fuel efficient cars on the market,
say a Geo Metro, getting some 50mi/gal. We'll assume that the
fully loaded Geo Metro with four passengers still gets the same
mileage. How much carbon is each occupant responsible for per
mile? Gasoline consists of a variety of hydrocarbons, like benzene,
for example. Each passenger is responsible for 1/200 gal per mile.
I think gasoline is heavier than water, but assuming it's at least
no lighter than water, with specific gravity 1, then 1/200 gal of
gasoline = (1/200)(~4 liter)(1000cc/liter)(1g/cc) = 20g gasoline.
Taking benzene (C6H6) as a typical constituent hydrocarbon, that
comes out to ((6x12)/(6x12+6x1)) x 20 g = 18.46 g of carbon available
for conversion to C02 in combustion, for which each passenger is
responsible.

Now, the cyclist. I can go at least a hundred miles on a thousand
calories of food, from personal experience. That's 10kcal/mi. Food
is broken down into glucose (C6H12O6), to produce energy. Refined
sugar is converted almost completely to such simple sugars, and
according to the USDA nutrient database (www.nal.usda.gov), it
provides 3.89 kcal/g. So, I need
((10kcal/mi)/(3.89kcal/g))x(6x12/(6x12+12x1+6x16)) = 1.028 g/mi
carbon.

That's nearly twenty times more carbon for a carpooler in the efficient
vehicle than for the cyclist. Even assuming electric vehicles, which
get the equivalent of some 150 mi/gal in energy consumption, the
cyclist doesn't even come close to the auto passenger in carbon
utilization.

Guy

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• Oops, correction. The specific gravity of benzene is of course lower than water. It s about .88, giving 16 g /mi of carbon for the vehicle passenger, vs. 1.0
Message 4 of 15 , Oct 26 12:51 PM
Oops, correction. The specific gravity of benzene is of course
lower than water. It's about .88, giving 16 g /mi of carbon for
the vehicle passenger, vs. 1.0 g/mi for the cyclist. The order of
magnitude of the result is unchanged. (Actual gasoline doesn't
consist of benzene, but of similar hydrocarbons; the differences
also shouldn't much affect the result).
• This is an intersting academic argument. But I doubt whether anyone would seriously entertain the notion that a car converts fuel to motion more efficiently
Message 5 of 15 , Oct 26 12:56 PM
This is an intersting academic argument.
But I doubt whether anyone would seriously entertain the notion that
a car converts fuel to motion more efficiently than a human being.

Mike

--- In carfree_cities@egroups.com, "Wilson, Jeff J"
<Jeff.Wilson@U...> wrote:
> You need to subtract from the carbon generated by the cyclist the
amount he
> would have spent anyway just sitting in a car.
>
> -----Original Message-----
> From: Guy Berliner [mailto:guy@s...]
> Sent: Thursday, October 26, 2000 11:21 AM
> To: carfree_cities@egroups.com
> Subject: [carfree_cities] Re: C02: cycling vs. driving
>
>
> Let's take up the challenge concerning cycling vs. driving
> as to which produces more C02 with a back-of-the-envelope
> calculation. The trick is to make rough approximations that
> are at least within an order of magnitude of the correct result.
> Thus, for example, if a liter is 1.057 quarts, we can round this
> to 1, as it won't affect the order of magnitude of the results.
> Then, we can make firm conclusions about quantities that differ
> by one or more orders of magnitude, as the difference can't be
> accounted for by mere error in approximations of the basic inputs.
> Here goes:
>
> Let's make some generous assumptions. First off, we'll assume
> we're using among the most fuel efficient cars on the market,
> say a Geo Metro, getting some 50mi/gal. We'll assume that the
> fully loaded Geo Metro with four passengers still gets the same
> mileage. How much carbon is each occupant responsible for per
> mile? Gasoline consists of a variety of hydrocarbons, like benzene,
> for example. Each passenger is responsible for 1/200 gal per mile.
> I think gasoline is heavier than water, but assuming it's at least
> no lighter than water, with specific gravity 1, then 1/200 gal of
> gasoline = (1/200)(~4 liter)(1000cc/liter)(1g/cc) = 20g gasoline.
> Taking benzene (C6H6) as a typical constituent hydrocarbon, that
> comes out to ((6x12)/(6x12+6x1)) x 20 g = 18.46 g of carbon
available
> for conversion to C02 in combustion, for which each passenger is
> responsible.
>
> Now, the cyclist. I can go at least a hundred miles on a thousand
> calories of food, from personal experience. That's 10kcal/mi. Food
> is broken down into glucose (C6H12O6), to produce energy. Refined
> sugar is converted almost completely to such simple sugars, and
> according to the USDA nutrient database (www.nal.usda.gov), it
> provides 3.89 kcal/g. So, I need
> ((10kcal/mi)/(3.89kcal/g))x(6x12/(6x12+12x1+6x16)) = 1.028 g/mi
> carbon.
>
> That's nearly twenty times more carbon for a carpooler in the
efficient
> vehicle than for the cyclist. Even assuming electric vehicles, which
> get the equivalent of some 150 mi/gal in energy consumption, the
> cyclist doesn't even come close to the auto passenger in carbon
> utilization.
>
> Guy
>
>
> To Post a message, send it to: carfree_cities@e...
> To Unsubscribe, send a blank message to:
> carfree_cities-unsubscribe@e...
• Let s add to the mix, the other emissions which are unique to cars, like for example carbon monoxide, nitrous oxides, etc. As far as I know the only other
Message 6 of 15 , Oct 26 1:03 PM
Let's add to the mix, the other emissions which are unique to cars, like for
example carbon monoxide, nitrous oxides, etc. As far as I know the only
other possible foul emission from a cyclist is the cyclist's bad breath.

Oh and lets talk about auditory emisions. Just the other day I was almost in
an accident biking to work... I nearly hit another bike. Why, because I had
become so used to listening for cars that I failed to recognize the bike.
Well anyways, after this I became atuned to the noice of cars and I would
like to point out that you can hear a car far away where a bike is virtually
silent. (well except for that rattle I gotta fix). I have sat at a quiet
intersection and counted the number of blocks away I could hear the car
after it passed me. I have been able to hear the car up to two miles away.
Note. this was a normal car not one missing a muffler or such.

>From: "Wilson, Jeff J" <Jeff.Wilson@...>
>
>You need to subtract from the carbon generated by the cyclist the amount he
>would have spent anyway just sitting in a car.
>
>From: Guy Berliner [mailto:guy@...]
>
>Let's take up the challenge concerning cycling vs. driving
...
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• ... In the arena of adversarial debate anything is possible and one of the most difficult thing for academics to do is to engage seriously with the absurd in a
Message 7 of 15 , Oct 26 1:41 PM
> This is an intersting academic argument.
> But I doubt whether anyone would seriously entertain the notion that
> a car converts fuel to motion more efficiently than a human being.
>
> Mike

In the arena of adversarial debate anything is possible and one of the most
difficult thing for academics to do is to engage seriously with the absurd
in a public place called democracy.

In political debate you have to impress "a jury" who may well include people
who will "seriously entertain" the most absurd notions. In politics as in
court you have to win hearts as well as minds and the former requires you to
find a language and style of refutation that owes little to the rational

"interesting academic argument" but that it lacks weight because no-one
"would seriously entertain the notion that a car converts fuel to motion
more efficiently than a human being." Guy lays out the issues in
conscientious detail for the jury (if you will) and so indicates that just
assuming that this is a matter of "common sense" might not be sufficient e.g
he humbly allows that the absurd assertion might be correct and dignifies it
with a far greater level of detailed refutation than you believe the claim
deserves.

Here he says "is the detail". To continue after that to claim that "a car
converts fuel to motion more efficiently than a human being" the claimant
must respond with the same amount of detail to the jury if they are to
maintain a credibility.

That would be much more difficult than just continuing to assert that
position as the ABD and others so frequently do. The jury will begin to
doubt that validity of the (to you and me - absurd) assertion that cyclists
produce more CO2 than motorists. QED

Simon
• When faced with a complex algebraic equation, a mathematician will attempt to clarify the problem by removing common factors from both sides. By suggesting
Message 8 of 15 , Oct 26 6:18 PM
When faced with a complex algebraic equation, a mathematician will
attempt to clarify the problem by removing common factors from both
sides. By suggesting that the essence of the argument was the ratio
between the efficiency of the human and the internal combustion
engine I was hoping to do the same thing.

If we re-serve the more fanciful statements of the auto lobby in base
terms we may help to expose the absurdities of their beliefs without
giving them the opportunity to hide behind "fuzzy math" (sorry,
couldn't resist that one)

That being said, I also admire the attempts by Guy and co. to refute
their logic more scientifically.

There's more than one way to skin a cat

>
> > This is an intersting academic argument.
> > But I doubt whether anyone would seriously entertain the notion
that
> > a car converts fuel to motion more efficiently than a human being.
> >
> > Mike
>
> In the arena of adversarial debate anything is possible and one of
the most
> difficult thing for academics to do is to engage seriously with the
absurd
> in a public place called democracy.
>
> In political debate you have to impress "a jury" who may well
include people
> who will "seriously entertain" the most absurd notions. In politics
as in
> court you have to win hearts as well as minds and the former
requires you to
> find a language and style of refutation that owes little to the
rational
>
> Your observation contains a paradox. You suggest that Guy's is an
> "interesting academic argument" but that it lacks weight because no-
one
> "would seriously entertain the notion that a car converts fuel to
motion
> more efficiently than a human being." Guy lays out the issues in
> conscientious detail for the jury (if you will) and so indicates
that just
> assuming that this is a matter of "common sense" might not be
sufficient e.g
> he humbly allows that the absurd assertion might be correct and
dignifies it
> with a far greater level of detailed refutation than you believe
the claim
> deserves.
>
> Here he says "is the detail". To continue after that to claim
that "a car
> converts fuel to motion more efficiently than a human being" the
claimant
> must respond with the same amount of detail to the jury if they are
to
> maintain a credibility.
>
> That would be much more difficult than just continuing to assert
that
> position as the ABD and others so frequently do. The jury will
begin to
> doubt that validity of the (to you and me - absurd) assertion that
cyclists
> produce more CO2 than motorists. QED
>
> Simon
• ... Cyclists are nearly quiet, but when cars are removed you can hear the cyclists, as well as birds and footsteps, a basketball player getting back home
Message 9 of 15 , Oct 26 6:27 PM
> Oh and lets talk about auditory emisions. Just the other day
> I was almost in
> an accident biking to work... I nearly hit another bike. Why,
> become so used to listening for cars that I failed to
> recognize the bike.
> Well anyways, after this I became atuned to the noice of cars
> and I would
> like to point out that you can hear a car far away where a
> bike is virtually
> silent.
Cyclists are nearly quiet, but when cars are removed you can hear the
cyclists, as well as birds and footsteps, a basketball player getting back
home dribbling his ball, etc. You hear the sound of life and people you
cannot feel when only a single car can pull out your attention, because you
need to locate its position and determine its direction to make sure there
is no potential danger.

your heart rate (stress), and your mobility. That's the reason why a totally
carfree area provides highly superior life quality w/r a place with cars
(even just a few cars).

> (well except for that rattle I gotta fix). I have sat
> at a quiet
> intersection and counted the number of blocks away I could
> hear the car
> after it passed me. I have been able to hear the car up to
> two miles away.
> Note. this was a normal car not one missing a muffler or such.

2 miles away! There should be very few cars where you were standing. I can't
hear the noise of a car that far because there are always other cars
passing. That's virtually a constant noise.

Louis-Luc
• By suggesting that the essence of the argument was the ratio ... by Guy and co. to refute ... I found both contributions helpful not only because I am (as a
Message 10 of 15 , Oct 27 12:39 AM
By suggesting that the essence of the argument was the ratio
> between the efficiency of the human and the internal combustion
> engine I was hoping to do the same thing.>
> If we re-serve the more fanciful statements of the auto lobby in base
> terms we may help to expose the absurdities of their beliefs without
> giving them the opportunity to hide behind "fuzzy math" (sorry,
> couldn't resist that one).> > That being said, I also admire the attempts
by Guy and co. to refute
> their logic more scientifically.> There's more than one way to skin a cat

I found both contributions helpful not only because I am (as a
non-mathematician) better informed but I am also better armed with both
complex and simple arguments to refute the assertion that a cyclist does
more damage to the environment than a car driver.

Simon
• fortunately my early morning commute takes me through a gridwork of blocks boardered by major arteries. The number of cars I see in this particular part is
Message 11 of 15 , Oct 27 7:33 AM
fortunately my early morning commute takes me through a gridwork of blocks
boardered by major arteries. The number of cars I see in this particular
part is only a handful. On this particular day there was not a car moving in
the residential area so I could hear this lone car as it sped it's way up to
join the major artery.

I get a lot of incredulity, about the fact that I bike to work. The most
common concern raised is having to fight traffic on a bike. Funny that
people don't understand that by biking I am not bound to the high speed
arteries and can amble through parks, down quiet residential streets, along
paths (both bike oriented and the impromptu paths of pedestrians seeking the
shortest path across an expanse). But once again, I am preaching to the
converted.

>2 miles away! There should be very few cars where you were standing. I
>can't
>hear the noise of a car that far because there are always other cars
>passing. That's virtually a constant noise.
>
>Louis-Luc
>

btw. Always thought the way we lay out paths across parks, universities etc
is wrong. Instead of some planner deciding that a path needs to go from a to
b, what we should do is plant the entire area in grass, wait for the
telltale paths of foot traffic to occur and then lay the paths there. Then
get rid of most of the grass and plant something more interesting. Of course
this is Regina, Sk and we start out with an empty field. This would not work
in the mountains.

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• My Transport 2000 newsletter arrived this morning and I thought you d like to read an item which I found disturbing for the BBC s credibility for impartiality.
Message 12 of 15 , Feb 28, 2001
My Transport 2000 newsletter arrived this morning and I thought you'd like
to read an item which I found disturbing for the BBC's credibility for
impartiality.

Roy P

TOP GEAR the BBC programme for road-hogs, joyriders and members of the
Association of British Drivers has received a series of blows to its
credibility -- if it ever had any in the first place. In November 1999 it
scheme through which the city's High Street has been closed to through
traffic during the day-time, the main shopping area of Cornmarket
completely pedestrianised and bus priority measures introduced wherever
possible. The aim has been to cut traffic, which was choking the city
centre, get more people on buses and improve the conditions for pedestrians
and shoppers.

The Oxfordshire County Council plan has been remarkably successful. More
people are using the buses, more people are visiting the city centre in
general, traffic congestion has been cut in most areas and air quality is
better. The majority of people who live, work or shop in the city are
supportive and, according to the Chamber of Commerce, companies are queuing
up to take shop and office space.

However, the Top Gear 'journalists' sent to the city to cover the story
missed all this. In a blatant attack on integrated transport in general and
the restrictions on cars in particular, the programme scoffed at the whole
scheme. To discredit it they showed film of empty buses, supposedly
rejected by shoppers, without saying they had waited until the buses had
dropped off all their passengers outside the shops before turning on the
cameras. Top Gear also said that business was on the point of collapse,
whereas in fact 200 retailers were waiting for retail space, and that most
county council staff were driving to work in the city themselves while
trying to stop others doing the same, again not true. The final straw came
in a series of street interviews with passers-by in which clips of anyone
voicing support for the scheme ended up on the floor of the editing room,
including a piece with an employee of the city council who had popped out
of the office to do a hit of lunchtime shopping.

The county council complained to the BBC, which was forced to admit the Top
Gear piece was biased, inaccurate and unfair. The Top Gear team was sent
back to Oxford to do the report again, which was broadcast in February
2000. This was mainly a heavily edited snippet from an interview with the
council's Director of Environmental Services, who felt the new item was
still biased. The council complained again, and the complaint was again
upheld.

The motoring hacks were faced with the ignominy of having to return a third
time to Oxford to redo the piece. This was finally put out in December and
consisted purely of a Top Gear presenter reading out some positive points

Staff at the county council have resigned themselves to this being probably
the best they're going to get, but the whole episode raises yet another
question mark over whether the BBC, with its public service remit and duty
to report issues with impartiality and fairness, should be broadcasting
motoring propaganda at all. Many people believe it is time this
irresponsible and unsavoury programme was involved in a fatal car accident
itself or taken to the scrapyard and left quietly to rot in a corner.

As for the Oxford traffic scheme, people are now calling for an extension.
• Dawson, got some URLs for us? ... ### J.H. Crawford Carfree Cities postmaster@carfree.com
Message 13 of 15 , Feb 28, 2001
Dawson, got some URLs for us?

>My Transport 2000 newsletter arrived this morning and I thought you'd like
>to read an item which I found disturbing for the BBC's credibility for
>impartiality.
>
>Roy P

###

J.H. Crawford Carfree Cities
postmaster@... Carfree.com
• I m a member of Transport 2000 Canada & Transport 2000 Quebec, but I haven t really heard of any thing until now. http://www.topgear.beeb.com/ Dawson ...
Message 14 of 15 , Mar 1, 2001
I'm a member of Transport 2000 Canada & Transport 2000 Quebec, but I haven't
really heard of any thing until now. http://www.topgear.beeb.com/ Dawson

-----Original Message-----
From: J.H. Crawford [mailto:postmaster@...]
Sent: Wednesday, February 28, 2001 1:14 PM
To: carfree_cities@yahoogroups.com
Subject: Re: [carfree_cities] Neutral Gear?

Dawson, got some URLs for us?

>My Transport 2000 newsletter arrived this morning and I thought you'd like
>to read an item which I found disturbing for the BBC's credibility for
>impartiality.
>
>Roy P

###

J.H. Crawford Carfree Cities
postmaster@... Carfree.com

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• Yes - but you can join in the forum on this web site and it s a helpful conduit for feeding moderate criticism into car culture (e.g spooking them). Drivers
Message 15 of 15 , Mar 4, 2001
Yes - but you can join in the forum on this web site and it's a helpful
conduit for feeding moderate criticism into car culture (e.g spooking them).
Drivers are deeply divided among themselves - a broad church. As for your
point about the BBC - it went commercial a long time ago ... caught a
Transatlantic virus via Mrs T about 20 years ago ... but there are still
people there who value the "impartiality" tag.

Simon

----- Original Message -----
To: <carfree_cities@yahoogroups.com>
Sent: Friday, March 02, 2001 4:40 AM
Subject: RE: [carfree_cities] Neutral Gear?

> I'm a member of Transport 2000 Canada & Transport 2000 Quebec, but I
haven't
> really heard of any thing until now. http://www.topgear.beeb.com/ Dawson
>
> -----Original Message-----
> From: J.H. Crawford [mailto:postmaster@...]
> Sent: Wednesday, February 28, 2001 1:14 PM
> To: carfree_cities@yahoogroups.com
> Subject: Re: [carfree_cities] Neutral Gear?
> Dawson, got some URLs for us?
> >My Transport 2000 newsletter arrived this morning and I thought you'd
like
> >to read an item which I found disturbing for the BBC's credibility for
> >impartiality.
> >Roy P
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