Brad Ideas - Holy cow: Walking consumes more gasoline than driving! - Comments

ebikes

Leigh — Mon, 28 Apr 2008 12:56:01 -0700

A similar argument, on a slightly different topic, is made about ebikes by Justin Lemire-Elmore on ebikes dot ca.

http://www.ebikes.ca/sustainability/Ebike_Energy.pdf

?!

Sara — Fri, 04 Apr 2008 07:04:11 -0700

"We eat, on average about 2700 Calories/day in the USA"

OINK!

OCR

brad — Sat, 29 Mar 2008 00:57:29 -0700

Off topic, and I haven’t yet tried it, but omnipage 16 says it will handle photos including the curvature that comes near the spine. I am cutting spines for my sheetfed, though, but only on books like old computer manuals.

Vegetarian option is of course better. Eat food from your own garden would be tops.

Vegetarian Cyclists of the world, untie!

Moz — Fri, 28 Mar 2008 16:21:00 -0700

Even in Oz it's not good, although we haven't yet achieved the true hideousness of the US food chain. So our food costs are lower but still obscene (total cost, not dollar cost).

The one thing you slid past was the vegetarian option - if a higher meat component pushes the cost up, lowering it pushes the cost down. For the most part, anyway - me eating roadkill when I'm cycle touring is probably fairly neutral, in that few people farm animals specifically to make them into roadkill, but a lot of native animals become roadkill.

Also, talk to us about packaging, Brad, that's another exciting area of "just how dumb are we, really?"

And finally, have you looked at scanning/OCR recently? I've bought a Sony PRS-505 (my first ever Sony {hoik spit} product), and I'm struggling to find some books online, so I'm using my 30D and a sheet of glass to scan books and OCR them. Slow, but beats paying another $2000 for a decent sheet-feed scanner and cutting the spines off my books. There's got to be a better way...

Misses the point

brad — Thu, 27 Mar 2008 10:25:52 -0700

The point is not to tell people to drive rather than walk. It's a point about the food system and the oil it consumes. That people who drive go farther isn't relevant to this analysis, because this is a per mile analysis to make a point, not an argument against walking. (Though in fact, I've often made the walk/bike vs. drive choice, especially when I worked 2 miles away and would bike commute half the time and drive half the time, depending on schedules and weather. But I made the choice for fitness reasons, not simply to be green.)

The point is how surprisingly inefficient we are as a system, using 400 gallons of fossil fuel every year to feed ourselves. (Because I don't commute, I probably burn about that every year to drive myself, but much more to fly.) What's amazing is that the comparison is even possible, not the fine points of it.

That is factored

brad — Thu, 27 Mar 2008 10:20:16 -0700

As noted, when I did the calculation, I worked out the extra calories consumed walking or biking compared to sitting down. So of course drivers eat. This analysis applies only if the walk/bike for transport was special exercise. For example, if you exercise every day, some days on a stationary bike and some days to get somewhere, you aren't changing your energy budget. If you decide to walk somewhere and otherwise you would not have done that exercise, then it takes extra energy.

However, again, this misses the point, which is not that we should sit down all day and not walk places. The point is we have created a system of agriculture where feeding ourselves consumes large amounts of oil, no matter what we do with the energy.

uh? don't drivers eat?

dave — Wed, 26 Mar 2008 23:30:27 -0700

I may be missing something (math makes me nervous and I might have blacked out during the presentation), but who said that bikers eat more than drivers? Assuming american bikers and american drivers eat the same 2700 cal pile o food, how is it you only add it to the biker's spreadsheet?

This comparison criticized numerous times

Anonymous — Wed, 26 Mar 2008 19:43:35 -0700

I'll probably end up in the spam-blocker for posting several links, but the driving vs. walking comparison has been made and criticized before. See:

http://www.stat.columbia.edu/~cook/movabletype/archives/2008/03/the_all_...

and

http://www.treehugger.com/files/2007/08/ask_the_ecogeek_6.php

with some of the key points being that people who drive, drive farther than people who walk, walk, and that if one considers all carbon wasted in our inefficient food supply system, it's certainly discouraging, but if one compares it to the carbon cost of creating and maintaining a car, the latter ends up the larger environmental loser.

Holy cow: Walking consumes more gasoline than driving!

brad — Tue, 25 Mar 2008 18:47:03 -0700

In my growing research on transportation energy economics, I’ve come upon some rather astonishing research. I always enjoy debates on total cost analysis — trying to figure out the true energy cost of things, by adding in the energy spent elsewhere to make things happen. (For example, the energy to smelt the metals in your car adds quite a bit to its energy cost.)

Humans are modestly efficient. Walking,an average person burns about 100 Calories per mile at 3mph, or 300 per hour, while sitting for the same hour burns around 80 Calories just keeping you warm. In other words, the walking 3 miles uses about 220 extra Calories. Calories are kilocalories, and one Calorie/kcal is about 4 BTUs, 4200 joules or 1.63 watt-hours.

While walking 1 mile burns an extra 74 Calories, on a bicycle we’re much better. Biking one mile at 10mph takes about 38 extra calories over sitting.

A gallon of gas has about 31,000 calories in it, so you might imagine that you get 815 mpg biking and 400mpg walking. Pretty good. (Unless you compare it to an electric scooter, which turns out to get the equivalent of 1500 mpg.)

But there’s a problem. We eat, on average about 2700 Calories/day in the USA, almost all of it produced by agribusiness. Which runs on fossil fuels. Fossil fuels provide the fertilizer. They run the machines. The process and transport and refrigerate the food. In many cases our food (cows) eats food produced with such high energy cost to feed us.

I’ve been digging around estimates, and have found that U.S. agriculture burns about 400 gasoline-gallon equivalents per American. Or 1.1 gallons per day, or about 10 Calories from fuel for every Calorie of food. For beef, it’s far worse, as close to 40 Calories of fuel are used to produce one Calorie of beefy goodness.

You can see where this is going. I’m not the first to figure it out, but it’s worth repeating. Your 3 mile walk burned 220 extra Calories over sitting, but drove the use of 2,200 Calories of fossil fuel. That’s 1/14th of a gallon of gasoline (9oz.) So you’re getting about 42 miles per gallon of fossil fuel.

If you eat a lot of beef or other livestock, and want to consider your incremental food as having come from beef, it’s around 10 miles per gallon.

So yes, if you drive your Prius instead of walking it’s going to burn less fossil fuel. If 2 people drive in a more ordinary car it’s going to burn less fossil fuel than both of them walking.

Biking’s better. The average-diet cyclist is getting 85 miles per gallon of fossil fuel. Still better for 2 to share a Prius. The beefeater is, as before only 1/4 as good. At 21mpg he’s better than a Hummer, but not that much better.

This is a fuel to fuel comparison. The fuel burned in the cars is the same fuel burned in the tractors. It has extra energy costs in its extraction and transport, but this applies equally to both cases. And yes, of course, the exercise has other benefits than getting from A to B. And we have not considered a number of the other external costs of the vehicle travel — but they still don’t make this revelation less remarkable. (And neither does this result suggest one should not still walk or bike, rather it suggests we should make our food more efficiently.)

And no, taking transit isn’t going to help. Transit systems, on average, are only mildly greener than cars. City buses, in fact, use the same energy per passenger mile as typical cars. Light rail is sometimes 2 and rarely even 3 times better than cars, but in some cities like San Jose, it uses almost twice as much energy per actual passenger than passenger cars do.

Happy eating!