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

Awesome

rico — Fri, 29 Apr 2011 10:21:02 -0700

Just giving you kudos for the "condoms" comment when everyone starts looking hot!!!! Point taken and thank you for the laugh.

Not quite

brad — Tue, 15 Feb 2011 15:13:06 -0800

As I have said, this article is about the inefficiency of agribusiness and not really about cycling, so indeed it is presented to be provocative, but its flaws are not as you report.

My reading suggests typical embedded energy in a car is the equivalent of about 1,000 gallons of gasoline. That’s a lot, but only about 15% of the gas the car might burn in its lifetime (YMMV of course.) So it doesn’t alter the equation a lot.
The roads have embedded energy too, and the roads are used by driving and cycling and shipping food. However, I would like to see good numbers on this embedded energy per vehicle mile or per vehicle.
The well-to-tank cost of gasoline is about 18%, which is to say that 82% of well energy makes it into your gas tank after the cost of refining and shipping, according to a variety of sources on this.

So I think even if you factor in car-unfavourable values for all these factors, it doesn’t change the equation a lot. The car is not efficient but neither is the agribusiness. I wasn’t looking at GHG here, but just fossil fuel energy. We could do a GHG analysys.

Finally in this case I don’t think it’s that unfair to actually take the simpler view that presumes the person already owns the car, and is deciding between driving and walking. That is in fact how people make the decision. Nobody is buying or not buying a car based on the idea that they would need to eat less food if they drove places instead of walking! The car/no-car decision is based pretty much entirely on much larger factors. Likewise the decision to build and maintain roads is entirely dominated by other factors as well. Can you dispute that?

On the other hand, the fuel burned driving is entirely dependent on the decision to walk or drive. And the fuel used by agribusiness is directly correlated to demand for its food products. If more people walk from time to time for exercise, we will not buy significantly fewer cars or build fewer roads. If people eat less beef, we will farm less beef. But in any event, these factors do not alter things much even when included.

I'd say I'd have to agree

herb — Tue, 15 Feb 2011 14:11:45 -0800

I'd say I'd have to agree with this article that your calculation mostly just functions for shock value, not because it in any way takes fully accounting of the energy used in each activity. You've taken a single snapshot of driving a car today so you can then nicely skew your results by only comparing the fuel that the car consumes to the *entire* process of raising beef: including the fossil fuels to provide the fertilizer; to run the tractors, to process and transport and refrigerate the food and to grow the food that the cows eat. Then you wave your hands and explain away why you don't need to take account any process that is required to get the car there. In this way you can rig the contest so driving always wins out over walking.

The cars and the infrastructure in which to drive them don't just appear out of thin air. They require mining raw materials, factories, labour, highways and roads, road widening, parking lots, filling stations and so on. None of this is included in your calculation.

To make it easier to avoid the embedded energy of the car you restrict your calculations based on a subset of humanity: those Americans adults that already own cars. Yes, if you rig the calculations this way you can avoid the messiness of reality. And by only including a small window of time for the car traveling you can avoid the messiness of calculating the energy requirements of providing the entire asphalt/concrete/landscaping infrastructure in order that the car can actually be there.

If someone chooses to walk, bike or take transit it means one less car and means that much less requirement for wider roads, freeways and parking lots. One can easily imagine this impact when one imagines what a place like New York City would be like if *everyone* decided to get from point A to B by automobile instead of by walking, biking or transit. From an estimate I saw some place, we could imagine the entire island of Manhattan being dedicated to roads and parking with nothing left for the actual buildings let alone parks or sidewalks. Currently only about 50% of NYC adults own cars and thank god for that (China is at 13%, Brazil at 15%, India at 1%! - http://en.wikipedia.org/wiki/List_of_countries_by_vehicles_per_capita). If they moved up to about the 95% car ownership rate of adult Americans you'd have to include the estimated energy costs of doubling (more or less) the entire NYC network of roads and parking lots. That's a huge amount of energy. Now imagine if the rest of the world moved up to America's car ownership level so they can have the option of taking the car to the corner store. Wow. Massive.

Unless you adjust your calculations to the *full picture*, you are hardly participating in "transportation energy economics" or "full cost analysis", but merely an exercise in convenient rhetoric.

even more points to add

smart ass — Tue, 28 Dec 2010 14:07:33 -0800

Another few points to consider about car riding:
- car drivers wash the cars once a week
- dirt from car exhausts and tires force people to use 1 extra load in the washing machine a week
- cars require wider streets which need more energy to build
- cars induce noise reduction infrastructure which needs energy to build
- cars induce a traffic police system which uses energy
- cars induce excessive oil use and thereby require the maintenance of an army with huge energy use
- car use leads to lack of exercise which must be substituted in a gym, which requires energy
- car use in cities makes people move into the suburbs, which comes with huge energy costs due to additional commuting
- car exhausts cause lung problems which cost energy in the health system
- car accidents cause energy costs in car industry and health system

Another few points to

Anonymous — Sun, 05 Sep 2010 17:10:53 -0700

Another few points to consider about bike riding:

they have 1 extra shower a day
they wash 1 extra load in the washing machine a week.

So factor the energy used to heat the water as well as for the washing machine.

How much fuel

brad — Tue, 24 Aug 2010 09:08:45 -0700

You’re doing pretty well if you only eat 2500 calories per day. It depends what your food is and how it’s grown when dealing with any personal situation. This article did the math on average US agriculture and beef.

You’re biking for around 10 hours you suggest, perhaps 5 hours more than you need to maintain your fitness level. So look up Calories consumed by a person of your weight cycling at 19mph and subtract Calories used sitting down. That’s how much extra food you are eating. The multiply by 10 to get fuel calories to bring you the average food. There are 31,500 Calories in a gallon of gasoline, thus 3,150 food Calories for each gallon-equivalent.

So how much fuel am I using

Willhub — Tue, 24 Aug 2010 07:27:22 -0700

So how much fuel am I using when I cycle up to 350 miles a week, on average I am doing around 200 miles a week at around 19mph average.

Probably eating around 2500 calories a day.

Agriculture

brad — Wed, 14 Jul 2010 11:22:33 -0700

You may have missed the note that this article was about the fuel inefficiency of agriculture.

You're missing the point -- correlation is NOT causation

Geodkyt — Fri, 09 Jul 2010 09:25:30 -0700

People who bike and walk commutes that others would noramlly drive do not eat less and waste less food BECAUSE they walk or bike.

They walk or bike BECAUSE they have a "greener" outlook -- which ALSO leads them to be less wasteful and healthier in other areas of their life.

"Green" leads to "healthy eating" and "bikes".

"Bikes" (in and of itself) does NOT lead to "healthy eating" and "green". It just leads to "more leg muscles, better wind". (Which, in the absense of "green" and "healthy eating" just leads to "shoving more processed crap down your gullet.")

A wasteful fat slob forced out of his car at gun point and on to a bike will STILL be a wasteful fat slob. He'll just be hungrer, so he'll eat more to compensate.

Mandating behavior does not equal mind control. Until you can psychically reprogram Fat Slob's mind to make him a green, healthy person, just like the people who choose to bike commuting distances, he will still be a fat slob with fat slob habits. (Of course, only now, he will hate bitterly the people who took away his comfortable car, and he will oppose their aims - no matter how good those aims might be - with ever power at his disposal.)

You cannot make people love you by forcing them to spend all their spare time with you, you cannot make people love your god and believe your religion by forcing them to convert at swordpoint and marching them under guard to church every Sunday, nor can you make someone an environmentally conscious vegan by forcing them to abandon lifestyle choices they want. It's the same fallacy in all three cases.

It's irrational to think otherwise.

It's irrelevant how healthy bicyclists are on average

geodkyt — Fri, 09 Jul 2010 09:13:32 -0700

It doesn't matter that bicyclists are healthier, waste less food, and consume less than cheeseburger gulping fat slobs in Hummers.

becuase the cheeseburger swilling fat slob is STILL going to be a cheeseburger swilling fat slob if you magically made his Hummer not work and forced him to ride a bike to work. When he gets near work, and he's tired, sweaty, and hungry from low blood sugar, he's going to pedal his ass into the McDonald's parking lot and tank up -- and it won't be on home grown vegetables that used non-petroleum based fertilizer.

He's just going to end up eating more. Oh, he'll have nicely toned leg muscles under the layer of fat. But he will still be a net consumer of more petroleum than if he drove to work.

You DO NOT make people into lean, green, health machines by putting them on bikes. People who WANT to be lean, green, health machines CHOOSE to ride bikes.

The fact that one may bike to work is less relevant to their health and overall calorie consumption than the fact that they have CHOSEN to do so.

Wasted food

brad — Sun, 17 Jan 2010 19:31:43 -0800

Well, other than what you have said about some people wasting more food than others (which is difficult to quantify) the amount of food wasted does not affect the calculations about how fuel-inefficient American industrial agriculture is, which is what this article is about. It is not about bicyclists.

What about the food we waste?

Oskar — Sun, 17 Jan 2010 05:45:26 -0800

You seem to assume that we realize all the calories we get from the agribusiness, but a lot (more than 50% according to some UK sources) is wasted (so most of it ends up in landfill producing CH4, and needs more energy to be refrigerated/waste-managed).

It is my impression, but a serious study should be conducted, that walkers and cyclists tend to finish-up what's on their dishes, while drivers are more prone to "waste" it. Also, driving to large supermarkets make people overshop, for carrying is not a problem; and overshopping is one of the primary reasons behind excessive domestic waste (in the UK alone, each day 5000 chickens are thrown in the bins for being past their sell-by date).

I say all those things

brad — Sat, 12 Dec 2009 02:16:28 -0800

However, the real point is the efficiency of agribusiness, not about the density of cities at all.

That is discussed in detail

Mark Denison — Fri, 11 Dec 2009 18:38:21 -0800

Brad, I understand now your point that the comparison the gas energy content of food is valid. But you are missing my second point. People with a higher body mass index (BMI) burn more calories at rest. As one puts on weight, the amount of calories that you can consume without gaining more weight increases. If cycling causes someone to maintain a lower body weight than they would without cycling their baseline metabolism will burn fewer calories all the time. The savings in calories will offset some and possibly all of the calories burned cycling (or any other exercise).

Professional cyclists in a stage of the Tour de France will burn 4,000 to 5,000 calories pushing their daily consumption up to 7,000 calories or more. Here your mpg calculation is valid and then some (you should even add in the team cars carrying wheels and spare bikes and the helicopter flying overhead with the TV camera). But a commuter who bikes 12 miles round trip every day burns only an extra 400 calories. A man who weighs 150 lbs with a normal BMI may increase his calorie intake say from 2400 calories per day to 2800 calories per day and maintain his body weight. However if the same man were to be 30 lbs overweight (probably average these days) he would have to consume 2880 calories per day to maintain his body weight. This is how cycling to work could mean no net increase in calories and thus no fossil fuel use. And it is an accurate observation that the average cyclist weighs 30 lbs less than the average non-cyclist.

There are compelling reasons to exercise that outweigh any concern about the environmental consequences of food calories. Being sedentary contributes to many diseases and reduces your lifespan. The obesity epidemic suggests that it is not normal for sedentary individuals to consume only a maintenance level of calories.

On another note, walking and cycling (and mass transit) are better for the environment because people who walk and cycle live in denser cities an enable cities to be denser. Above all automobile use leads to more miles traveled and even if the energy use is no worse per mile the increased distances result in more GHG released.

The real point of your analysis (which really is brilliant) is that cities need to become denser. Outside the market forces that direct development, communities need to rethink policies that promote low density automobile dependence - things like parking requirements, setbacks, minimum lot sizes, street widths and the like.

That is discussed in detail

brad — Mon, 07 Dec 2009 11:02:49 -0800

And it is also not true that anybody does not replace every calorie consumed with one eaten. If you don’t do this you lose weight, and eventually die. Everybody.

This compares fuel in cars to fuel in tractors and machinery, plus fuel used to make fertilizer. It’s fuel to wheels for both.

Holy cow: Walking consumes more gasoline than driving!

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

Note to new readers: This article explores the consequences of using so much fuel to produce our food. If you come out of it thinking it’s telling you to drive rather than get some exercise, you didn’t read it! But if you like surprising numbers like this, check out the rest of my Going Green section and other sections.

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. Again, this is the extra calories.

A gallon of gas has about 31,500 Calories in it, so you might imagine that you get 815 “mpg” biking and 400 “mpg” walking. Pretty good. (Unless you compare it to an electric scooter, which turns out to get the equivalent of 1200 mpg from pure electricity if you allow the same perfect conversion.)

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 even more food produced with very high energy costs.

I’ve been digging around estimates, and have found that U.S. agriculture uses about 400 gasoline-gallon equivalents per American. Or 1.1 gallons per day, or about 10 Calories (40 BTU) from oil/gas for every Calorie of food. For beef, it’s far worse, as close to 40 Calories of oil/gas (160 BTU) 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 gas-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. A Hummer does better!

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 sort of 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, picking 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. Taking existing transit vehicles that are already running is green, of course, but building inefficient lines isn’t.

Many people take this idea as a condemnation of cycling or exercise. It isn’t. Cycling is my favourite exercise. It is a condemnation of how much fossil fuel is used in agriculture. And, to a much lesser extent, a wakeup call to people who eat the average diet that they can’t claim their human-powered travel as good for the planet — just good for them. What would be good for the planet would be to eat a non-agribusiness diet and also walk or bike. How your food is farmed is more important though, than where it comes from. It’s the farming, not the shipping, that’s the big energy eater.

Obviously if you were going to need the exercise anyway, doing it while getting from A to B is not going to burn extra oil. Human powered travel well above the need to exercise is the only thing that would hurt, if fueled by U.S. agriculture. And eating a high calorie diet and not exercising would be just as bad.

Happy eating!

What’s not wrong with these numbers

As I note, since most of us need to exercise anyway, this is not at all a condemnation of walking and cycling, but rather of the amount of fossil fuel that agriculture uses. However, a lot of people still find faults with this analysis that I don’t think are there.

No, it doesn’t matter that making the fuel costs energy. It’s (roughly) the same fuel going into the tractors as going into the gas tanks. We’re comparing fuel in tank to fuel in tank. But if you really want to factor that in, about 82% of well energy makes it to the gas tank of the car or tractor.
Yes, I do account for the fact that just eating or sitting consumes calories. This calculation is based on the extra calories that biking or walking take, compared to sitting in a car. The base “keep you alive” calories are not counted, but they do require more fossil fuel to create.
I don’t include the energy required to make a car, which ranges from 25% (Prius) to 7% (Hummer) of its lifetime energy usage. However, most cyclists and pedestrians still own cars, so this is still spent if it sits in the garage while you walk. And while a 2000lb car may take 60-100 times as much energy to make as a 30lb bike, this is not so large a difference if expressed per lifetime vehicle-mile.
This is based on the USA averages. Of course different food means different results, but doesn’t change this story, which is about the average eater.
I don’t include the energy needed to build roads for bikes, cars and food delivery trucks. The reality is, we’re not going to build fewer roads because people take some trips walking for exercise. Nor are people going to not buy a car because they do that.