Bicycle EROEI

Should CAA endorse a massive shift of transportation to bicycles?
Well, that question came up at the May meeting, tossed out as sort of a no-brainer during the discussion of why CAA has stated it hasn't taken positions on issues.
Well, the question gave me pause. Why not? What could the down side possibly be? But before rushing into supporting this, I decided to do an EROEI calculation to convince myself that it really is a good idea, strictly from an energy standpoint. As I?ve been a serious bike guy for the last 40 years or so, I will use my own experience as typical, and then do some guestimates on stuff that I don?t have the time or background to prove.
I?ve kept track of all my travels in Austin for the past 3 years on a bicycle computer. It comes out to about 2000 miles per year. I average 12 mph around town, which gives me about 166Hrs. of pedal time in a year (an average of almost 30 minutes/day, which is actually very healthy for a person my age, I?m told).
My bicycle engineering book says that a normal person, generating 200W of power, can pedal almost all day long. Based on that datum, I calculate that the energy expended in my travels in a year is 200W * 166Hr = 33.2KW-Hr.
Now, I walk at a 3 mph pace, using the same power, 200W, which means I get a 4X mechanical advantage by riding a bike. That is to say, to travel that same 2000 miles on foot would take me 666 hours, with a total energy expenditure of 133KW-Hr. So, I can claim that the bicycle ?produces? the difference, about 100KW-Hr annually.
Now let?s say that my bike lasts for 5 years (I?m assuming that the replacement of chain rings, derailleur, tires, tubes, lube, chains, cables, etc essentially replicates the energy investment of the bike in 5 years). That is 500 KW-Hr of energy produced by my bike over its lifetime. The question is, how much energy did it take to mine the ores, produce the rubber, build the bike, transport it to the bike shop, and keep the lights on and cash registers humming for that bike to end up under my posterior?
Well, a gallon of oil contains the equivalent energy of about 38KW-Hr, which means that mining the raw materials, manufacturing the bike, shipping it, storing it, maintaining places of business and warehouses, etc cannot consume more than 13.2 gallons of oil, which yields the amount of gas you?d use driving your SUV from Austin to Dallas - otherwise the EROEI goes negative.
Admittedly, this analysis is a bit sketchy, but based strictly on energy economics, I would hesitate to make any broad recommendations until I had a clearer view of the energy expenditures for manufacturing a bike, and what steps can be taken to increase the energy output obtained and/or decrease the energy inputs needed. Now, if you ask me if I recommend biking as a way to stay fit, have fun, lower your carbon footprint, commuting stress and road rage, and still keep commute times realistic, the answer is overwhelmingly yes! I have a very personal relationship with my bike. But for CAA to endorse them strictly as a sustainable method of transit, I?d have to say ?not so fast, my friends?.

Whoa. Had to read that one twice, Larry.

I think of bike-based transit in terms of reducing an overall energy draw but everything's going to have an EROEI timeframe. As long as humans have to maintain a heartbeat, we'll expend energy that needs replacing with fertilized food. In my case (heart still beating, gratefully), I have a 1989 mountain bike that I've modified into a road bike of sorts. Before me, a friend of mine rode it for 1000's of miles per year, so the EROEI has long-since passed. All of the miles I put into it now are positive if only the energy inputs to making the bike are considered.

My scenario reminds me of something I've found in looking into bikes for my wife: many people have bikes sitting in their garage gathering dust. The EROEI timeframe for those rusting hulks will be decades if not centuries...unless they get them down from the hooks in the garage and start riding them.

I think most folks don't ride for two reasons, one they'll state and the other they'll keep hidden: a) they're afraid (sometimes reasonably) that they'll get hit by a car; and b) they're out of shape and don't want to expend the lung capacity bicycling to-and-fro' would require. If we take away the stated reason for not riding -- by eliminating or reducing the perceived/real likelihood of being hit by a car -- then the EROEI on bikes en masse should be reduced considerably. An economic hit like we're beginning now will encourage the used-bike trade and we might even see some cases like mine of immediately-positive EROEI.

Sounds like you know this already, but I'll state the obvious: once folks begin putting even 1/4 the effort into maintaining their bikes as they are to maintain their cars, their bikes can last more than a five-year cycle, increasing the EROEI greatly and seriously reducing the overall energy draw compared to other forms of transportation.

I personally endorse city planning that accommodates protected bike lanes (like they used to have going up and down Guadalupe in front of campus) as well as mass transit. However, I recognize that, in today's culture, others might shy away from a group that wants them to "take their lives into their hands" on the road by riding their bikes. So I'd say a group endorsement of bike-riding would limit the rest of CAA's message.

Those are my $0.02.

Interesting discussion. I think what I see happening here is that we're on the verge of paralyzing ourselves into lack of action because something isn't a perfect EROEI, or because the production of bikes causes pollution too, which it certainly does.

I think we need to remember where our society is RIGHT NOW: we are at Peak Oil, which means we are using 85 million barrels of oil every single day, spewing toxic pollutants into our atmosphere, living lives that make us isolated, unhappy and less social beings by using our cars and using our energy as a means to enrich a tiny portion of the planet to the detriment of everyone else.

We shouldn't be letting ourselves be bogged down in discussions like this, I think. I think we need to forget about the perfect solution and just start working towards ANY solution, b/c that will at least be movement. What need is implementation, momentum and action. The death of perfection and the birth of implementation.

Maybe the EROEI isn't that great on a bike, but I'm damn sure its better than a car. And If I walk and have to buy shoes on a regular basis to make that happen, then I am going to do that and make that exchange. Not b/c I've calculated the EROEI, but because its the more human choice. It strengthens society and the fabric of our community. It keeps me in shape. Its the right thing to do.

I think the EROEI discussion will be had increasingly as the years go by. But what we need right now is movement and action. We are still using the most oil that humanity has ever used, and we need to use that energy to build solutions. Oil got us into this mess and we NEED oil to help us out of it, but that has to happen now! We can't keep waiting.
My two cents

Jon

The better is the enemy of the good.

I am the guilty party in tossing out the "no-brainer during the discussion," so I guess I should clarify what I meant. The relevant issue here is car vs. bike, since our society uses the car as the predominant mode of transportation.

If we are trying to convince folks to completely give up cars AND bikes in favor of walking, we will justly be accused of being Luddites more extreme than the Amish or be dismissed outright for overt omphaloskepsis.

We are not seriously suggesting that there is not a significant reduction of fuel use riding a bicycle vs. driving a car, are we?

Even if we concede for the sake of argument that the individual already owns the car and does not already own a bicycle and that they would be buying the bicycle new and we will ignore the fact that, at some point, they will be acquiring a replacement car, I cannot believe that the fuel costs of manufacturing and maintaining the bicycle and dealing with it's impact on other fuel costs exceeds the costs generated by the car.

Specifically, there is maintenance of the car and it's tires, replacing of worn parts, etc. There is the cost of maintaining a road for cars and parking for cars. It takes a lot of bicycles to meet the road wear and parking costs of one car.

This is not counting the affects on the health of the person driving, the relatively higher safety of a society that has more bicyclists and less motorists (fewer car miles on the road means fewer fatalities, etc.).

Let's assume that a car can get 20 MPG all inclusive (which is probably absurdly generous when you factor in realistic gas mileage, wear and tear to car, road and tires). Lets look at 2000 miles per year for five years, 10,000 miles. We'll call that 500 gallons of gas. Based on your calculation, the bike cost 13.2 gallons of gas. Saving 486.8 gallons per year is significant , no? And this does not include the fuel costs to manufacture the car.

Frankly, I would be shocked if the incidental wear and tear costs of a car, car tires and road maintenance would not significantly exceed 13.2 gallons of gas for 10,000 miles of travel by car.