Sunday, May 04, 2008

Oh no! It's a story problem!...

Suddenly farmers are trying to do a kind of math different from what they are used to. We're calculating carbon emissions, for example. The only problem is we tend to work backwards. The answer - which we can recite by heart - is ethanol is good for the environment. Especially corn ethanol.

Now if we could only get those darn numbers to line up right! No problem, we'll just force them. And the grain media is doing its best to help out.

[Bloggers note: I'm getting a mess of incoming about how the "farm media" should be fighting back against ethanol slurs. Well, my read is there is a significant chunk of "farm" that is doing the slurring. For example, the livestock sector isn't thrilled with mandates that force up feed costs. So let's be clear about who is likely to step up as ethanol boosters. I refer to them as the "grain media".]

Here is a prime example of how the grain media can wander off the Competence Reservation.
Dan Looker at Successful Farming tries to score a gotcha on cane ethanol and those sneaky Brazilians.
Then I met John Alexander, the CEO of a large, diversified farm and ranch in Florida called Alico, Inc. (READ MORE) Alexander and Alico's energy consultant, Craig Evans, looked into making ethanol from Alico's sugarcane. They can't and still comply with U.S. environmental laws. Every gallon of sugarcane ethanol produces 10 gallons of liquid waste called vinasse. "This is something the press hasn't covered," Alexander says. Sugar has another problem. Its leaves and trash are burned off to make harvest easier and safer. That's not too green, is it? Releasing all that global-warming CO2 into the air. Alico's own ethanol production is likely to use a related crop -- energy cane -- without field burning. [More]
I read Dan's stuff all the time, and this strange departure from reason surprised me. Well, let's walk through this. Burning cane residue does release nasty carbon into the air, BUT it is carbon that earlier in the year was in the air. (Green plants - photosynthesis - Biology I - ring a bell?)

Now compare that to coal. That carbon was safely sequestered underground until it was burned to fire a corn ethanol plant here in the US.

Anybody see why cane burning to heat ethanol stills is labeled "greener?" A hint: Recycling carbon is different from introducing new carbon.

The issue for me here is I suspect Dan had the answer before he wrote the words. And because agriculture is mostly turning green to appear less like a target (or receive a carbon credit payment) we haven't done the homework we should.

We also have problems with the math. And we're not alone. Consider the scientific hullabaloo that arose when somebody suggested driving was better for the environment than walking.
How can that be? Because Mr. Goodall takes into account something that a lot of environmentalists don’t: the human energy expended in averting fossil-fuel use. “Walking is not zero emission because we need food energy to move ourselves from place to place,” he writes. “Food production creates carbon emissions.” Now, you could argue that most people are oveweight and so could use the exercise anyway, but that doesn’t mean that they’re not going to consume calories to replace the ones they’ve burned. In fact, some experts argue that most people do in fact simply eat more to compensate (which is one reason so many people remain overweight). And judging from the fitness of the pedicab drivers I’ve seen, they don’t have much weight to lose anyway.

If you walk 1.5 miles, Mr. Goodall calculates, and replace those calories by drinking about a cup of milk, the greenhouse emissions connected with that milk (like methane from the dairy farm and carbon dioxide from the delivery truck) are just about equal to the emissions from a typical car making the same trip. And if there were two of you making the trip, then the car would definitely be the more planet-friendly way to go. [More]
Good heavens, that stirred up some folks with computers. And the result is: Don't eat meat if you walk. (I am not making this up - look at the numbers yourself.)
Could walking be worse for the planet than driving? This startling idea has recently received coverage in New York Times blogs1 and beyond. In the following, we look at the numbers behind this comparison to determine whether the life-cycle2 greenhouse gas (GHG) emissions of food needed to replace the calories burned in walking a certain distance could exceed the life-cycle
emissions of the fuel needed to drive a car the same distance. Our conclusion: it depends on the assumptions.3 Driving turns out to be better only if you compare it to a very greenhouse-gas- intensive food, such as beef. When we consider an average American diet, which is still energy- intensive compared to diets in other countries, walking is better for the planet. While we commend
growing efforts to understand the complex implications our purchases, choices, and activities have on the climate, we caution against making hasty behavioral changes based on analyses and comparisons that may be faulty or rely on unrealistic assumptions. [More via Freakonomics]
And don't even think you know the right answer to paper vs. plastic and disposable diapers.

These calculations are far from simple, but it appears we know people like simple answers and so we give them simple answers.

They just don't work.


dj said...

The problem is we don't just drive the 1.5 miles but rather 10 miles to rent the video that we can sit in our recliner and watch while scarfing down a bag of chips and 6pack of pop. You are still consuming the energy and haven't burned up any!!

Ol James said...

The one thing that I have not heard mentioned is the cost. We know what a barrel of oil is going for, but I have not seen,(maybe I'm not looking in the right place), what it actually cost to make a gallon of Ethanol either corn or sugar or celulose etc., etc,. The only thing I have heard is it will be around the value of fuel + or -, at the current price. hmmm
But from all I have seen on the Internet, it looks as tho sugar cane may have the advantage. It can produce it's own energy to run the processing plant.

Anonymous said...

I've always thought a study should be commissioned to determine the impacts of a vegetarian diet on water quality. Are humans better and more efficient at utilizing animal protein vs. vegetable protein. And what about the methane issue, does more green matter equate to larger, human methane emmissions?

This is only partly tongue-in-cheek. I am sure it is something the veggie mafia would promote if better for the environment. And how about a surcharge for overweight individuals. Those overweight must be responsible for larger and more harmful impacts to treatment plant effluent. After we ban trans-fats, this will be next!