Posts Tagged ‘climate change’

Don’t much care about any of the substantive points raised here, but I do want to point out that online grocery shopping is not about protecting the environment. I find it very hard to believe that such a system would be more environmentally friendly than our current system. I suspect they would net out roughly the same, as each system has different exploitable energy efficiencies not possible in the other.

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Back in January I made a very simple case for ethanol, and then I mentioned that I would write a post on why I don’t think that corn ethanol increases the price of food. I started putting together data to make my case, but never had a chance to finish it up. Well I finally did, and so here we go.

As the argument goes, making ethanol out of corn raises food prices because, instead of eating the corn, we’re burning it. But ethanol is made out of yellow corn, which is not used in food for people (that’s sweet corn). So a more persuasive form of the argument is that making ethanol out of corn raises food prices because, rather than feeding the corn to cows, we’re burning it. That raises feed prices, due to  competition for corn supplies and thus an increase in the price of corn (ie an increase in the price of feed) which gets passed along to the consumer at the grocery store. When we’re talking about ethanol raising food prices the story is really about corn used (or not) for animal feed.

Here’s the amount of corn ethanol we’ve produced in the US in the past 20 years:

Prior to the 1990’s, basically no one was making fuel ethanol out of corn (or anything, for that matter) in significant quantities. Corn ethanol didn’t really get going until the late 90’s and grew explosively in the past decade.  Last year, we made about 14 billion gallons, which is only 1 billion gallons away from the upper limit allowed by the EPA. With such rapid growth, where did all the corn come from and what does that mean for food?

As it turns out, the amount of corn harvested in 2010 was nearly double what was harvested in 1993. So did we plant twice as much corn? No! Instead, crop yields (bushels of corn harvested per acre planted) increased significantly, and the land dedicated to corn production increased by only 20%. Further, the total amount of cropland in the country remained flat over the time period, which suggests that no new land was brought into production:

But was doubling our corn harvest enough to make up for the demand caused by ethanol production? Well, in a word, yes. In 2010, and extra 4.5 billion bushels of corn were converted into ethanol than in 1993. But the corn harvest increased by 6.1 billion bushels over that time frame, leaving an extra 1.6 billion for other uses. And in fact, no major corn consuming sector saw a decrease in the amount of corn they utilized. Here’s the amount of corn used in ethanol production, animal feed, exports, and all other industrial uses (starch, sweeteners, beverage alcohol, etc):

But pay particular attention to the feed category, because as I mentioned that’s the one we care about when it comes to the question of food vs. fuel. More corn is fed to animals after the “ethanol boom” than before it. But what about that downwards slope starting in the mid ‘00s, coinciding with the really rapid part of ethanol’s expansion? Doesn’t that show that actually we’re feeding less corn? Well, no. This is because when you make ethanol out of corn, you also make something called DDGS. DDGS is all the parts of the corn left over that didn’t get fermented away, plus all the yeast cells that did the fermenting. This is important because DDGS is high in protein and fat, which means you can feed it to cows. In fact, DDGS is such a good feed that you can give a cow less DDGS than you would corn to achieve the same result. In practice, about one third of the corn that goes into an ethanol plant winds up as DDGS, and 1 kg of DDGS fed to a cow is equivalent to feeding 1.2 kg of corn. So, in reality, 40% of the corn that goes into an ethanol plant still winds up getting used as feed. We can ferment our corn and eat it too! Here’s what the above graph looks like when you account for the corn returning to feedlot as DDGS (the light blue line, on top):

When we account for the DDGS being returned, feed corn has increased by 25% since 1993! Now that I’ve shown that feed doesn’t face the significant competitive pressures that the food vs. fuel myth implies that it does, what about food prices? As my benchmark food price, I’m using the food component of CPI, over the two decades 1990 – 2010. Remember, the argument goes that ethanol increases the price of corn and thus the price of food so if this is true we would expect to see that the prices of corn and food would increase (at least partially) together. Here’s a comparison of the monthly change in the prices of food and corn over 20 years:

Can you spot a trend? I can’t. There’s no correlation between the two data sets. But monthly price data are noisy, so let’s take a look at the yearly changes:

Here we can see that there is a very weak correlation. A simple linear regression predicts that if corn prices double we can expect to see a 1.6% increase in the price of food, which is less than inflation. Of course the correlation is so weak, and the fit so poor, that the predictive value of the trend line is essentially worthless. However, if an increase in corn prices caused an increase in food prices as the food vs. fuel argument claims, then we should see a strong positive correlation. It’s simply not in the data.

Finally, let’s take a look at the actual changes in food prices. Luckily for me, NPR published a piece on food prices just the other day, so now I don’t have to go digging for the data. Instead, I’ll shamelessly steal theirs:

Between 1982 and 2012, a time span that has seen the amount of fuel ethanol produced increase over 1000 times, food prices have dropped. Significantly. The biggest decreases amongst meat have come from chicken and beef, both of which are fed with corn.

(Data sources: USDA NASS, BLS, FRED)

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I had a busy weekend and didn’t pay much attention to the news, so this morning I wanted to see what I missed. Mostly, it was just a lot of stupid.

First off, we have Bill Nye the Science Guy, pissing off Christians with science in (predictably) Waco, TX:

Bill Nye, the harmless children’s edu-tainer known as “The Science Guy,” managed to offend a select group of adults in Waco, Texas at a presentation, when he suggested that the moon does not emit light, but instead reflects the light of the sun.

But nothing got people as riled as when he brought up Genesis 1:16, which reads: “God made two great lights — the greater light to govern the day and the lesser light to govern thenight. Healso madethe stars.”

The lesser light, he pointed out, is not a light at all, but only a reflector.

At this point, several people in the audience stormed out in fury. One woman yelled “We believein God!” and left with three children, thus ensuring that people across America would read about the incident and conclude that Waco is as nutty as they’d always suspected.

And then there’s this series of billboards, suggesting that if you believe in global warming, you might be a terrorist.

And you thought Jeff Foxworthy couldn’t get any worse.

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Kevin Drum highlighted the video below looking into biofuels from algae. I want to make a few points regarding this, because there’s alot here I think people don’t understand:

First off, the chart at the 2 minute mark. We see that it takes far less land to make an equivalent amount of oil from algae than from corn or soy. Well, OK, but lets unpack that a bit. When we grow corn to produce biofuels, we do a few things. First, we have to get the corn out of the field. Then, we have to get at the part we make the biofuel out of, the starch. Then we make the biofuel, which is ethanol. For algae based biofuels, we have an analogous process. First, we have to get the algae out of the water. Then, we have to get at the part we make the biofuel out of, the oil. Then, we have to make the biofuel, which is biodiesel.

So what’s my point? Well, getting corn out of the field is really, really easy. Getting algae out of the water is really, really hard. In fact, no one knows how to do it efficiently yet. You can centrifuge it, filter it, or you can even feed it to fish and collect the algae-containing fish poop (seriously). But it isn’t efficient.

Next, we have to get at the part we make the biofuel out of. In corn, thats the starch. We can either purify the starch and ferment only it (thats called wet milling) or we can just grind up the whole corn kernel and ferment the whole thing (thats called dry grind). In either case, not so hard. Algae though is a different story. Once you’ve gotten your algae out of the water, you have to get your oil out of your algae. To do that you have to break open the cell, and extract the oil. People have used supercritical carbon dioxide (that’s what Garden State Bioenterprises wants to do, I believe), they’ve used hexane, and other methods, but again, none of that is efficient. Or cheap.

So all that efficiency you gain by using less land? Gone, gone, gone, and then some, before you’re even ready to start making your fuel.

As for the statement at 2:20 that CO2 used to grow algae offsets the CO2 used when it’s burned, well I agree. Algae does photosynthesis, which means it takes in CO2 and sunlight, and makes more algae and oxygen. Then when you burn it, CO2 is given back off. Its the same for every plant. Keep that in mind, because people seem to suddenly forget that fact when they talk about ethanol.

A lot of people seem to support algae biofuels but at the same time are against corn ethanol because they think it takes more energy to make and gives off more greenhouse gasses than oil. I disagree with those claims, but would just like to point out that algal biofuels take significantly more energy (and thus more GHGs) than ethanol to make.

Bottom line, fuel from algae is inefficient and costly to make. So much so that we haven’t figured out how to do it yet. Ethanol, on the other hand, is very efficient and relatively cheap to make. So why does algae get all the media love?

(ps: yes, a couple months ago I promised a post about why I think the anti-corn ethanol arguments are wrong. I haven’t forgotten. I’m working on it. Actually them. It’s going to be a multi-part series. Because this is my blog and I’ll nerd out if I want to damn it)

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Kevin Drum has a post up today in which he describes the origins of the culture war, stating that liberals started it by pushing for things like marriage and gender equality. He thinks that liberals really ought to own it:

Every time I hear some liberal complaining about the way that conservatives keep turning everything into a new front in the culture war, I feel a twinge of chagrin. Why are we complaining? We’re the ones who really own the culture war, and we should be proud of it. It was a war worth starting and a war worth winning.

While I agree with the larger thesis here, I have to quibble with the point above. I think the complaint about things being turned into a culture war is entirely valid when discussing things entirely unrelated to culture.

Take, for example, climate change. At issue here are scientific questions (is the climate changing? If so, why?) and policy questions (what are the implications? What, if anything, should be done?). The scientific questions are largely settled within the scientific community. The policy questions are entirely unsettled, and a vigorous debate on them is very reasonable. But what is not reasonable is the attempt to twist a scientific issue and a policy debate into a biblical narrative or some kind of weird  us vs socialists nationalism.

Take for another example this post, describing the culture-war-ification of the Chevy Volt. Why should a car be debated along  “conservatives should buy SUVs” and “liberals are smelly hippies” lines?

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Senator Inhofe (R-OK) has a new book entitled The Greatest Hoax: How the Global Warming Conspiracy Threatens Your Future.

In it, he argues that the bible disproves the existence of climate change:

“Well actually the Genesis 8:22 that I use in there is that ‘as long as the earth remains there will be seed time and harvest, cold and heat, winter and summer, day and night,’ my point is, God’s still up there. The arrogance of people to think that we, human beings, would be able to change what He is doing in the climate is to me outrageous.”

So, why did I waste my time on those degrees when all I had to do to be good at science was read my bible?

Is it arrogant to think that we, as human beings, would also be able to change what He is doing in our bodies? My next book will be titled The Greaterest Hoax: How the Medical Conspiracy Threatens Your Future.

Is it arrogant to think that we, as human beings, would be able to change what He is doing with the geography of the planet? The Greaterester Hoax: How the Man-made Lakes Conspiracy Threatens Your Future.

The real threat to our future, of course, is that idiots like this keep getting elected. And climate change.

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