Sustainable Ethanol: not an oxymoron? by Shodo Spring

A rough appraisal of the promises in

Alcohol Can Be a Gas! Fueling an ethanol revolution for the 21st century, by David Blume.


By Shodo Spring, 2008


Today I opened another email, urgently asking me to contact Congress and oppose all biofuels of any kind. It was fervent, impassioned, and certain. As they all are, as I once was. Ethanol means corn, genetic engineering, industrial agriculture, and world hunger. Right?


First, about the image of ethanol: David Blume, who proposes small-scale sustainable ethanol as part of our long-term future, says: "A complete and total wall has been erected against any positive stories about ethanol, built brick by brick in a months-long relentless campaign by the American Petroleum Institute."


Did you get that? The focus on obviously-stupid corn-based ethanol has been fostered by big oil, and if when we think ethanol we immediately think "corn – causes starvation" it is because of big oil's advertising efforts. When we discuss other biofuels, we focus on scarcity of agricultural land and not getting distracted from the need for energy descent. Yet these myths (not enough food, not enough land) were debunked in 1986 by Frances Moore Lappe; somehow we just weren't listening.


I had been puzzled when my friend and Permaculture teacher Peter Bane spoke favorably about Alcohol Can Be a Gas! I promised myself to investigate at the nearest opportunity, and did so as a project for an environmental physics class in fall 2008.

I spent many hours with the book and on the Internet, checking facts, finding data, trying to "do the numbers." I didn't come close to completely figuring it out – but I did enough to conclude that Blume is right. Ethanol can be grown sustainably and, on the land we have, we can grow enough ethanol to power a reasonable society – not the insane consumer society we have now, but a more reasonable way of life.


Revisiting my work 6 months later, I revised a few things and offer these conclusions:

  1. Ethanol can be produced sustainably; in fact it can help rehabilitate depleted soils. It's most efficiently produced on a local scale. Done right, it could even help reduce world hunger.
  2. Cars and trucks can work well with ethanol, and the conversion is fairly easy.
  3. We could make a lot of ethanol now, using waste from the Industrial Growth Society, and it would make the energy descent less painful.
  4. The sustainable culture in our future would do well to include some ethanol, sustainably produced, to be used for emergency vehicles, buses, trains, community vehicles (shared pickup trucks?), and possibly even in industries such as manufacturing bicycles, recycling metal for tools, maybe keeping phone and Internet systems alive.
  5. We need more people involved in exploring this; we need to think for ourselves.

Here is a brief summary. Rather than footnoting, I'll cite Blume's work as I go along, and list other references at the end.


1.    Ethanol can be produced sustainably; in fact it can help rehabilitate depleted soils.

Cellulosic ethanol is made from a wide variety of plants – perennial grasses, trees, and shrubs – which can be grown in polycultures in ways that enrich the soil. The byproduct of ethanol production includes protein, fat, some cellulose, yeast, vitamins, and minerals. It is a high quality cattle feed which actually is healthier for cattle than grain and grass. These byproducts can be directly spread on fields as a high-intensity fertilizer, or fed to livestock and the manure returned to the fields. Or they can be put into the compost, or used to grow mushrooms. The most efficient setup is a small plant (producing under 500,000 gallons per year), with pipelines sending byproducts to nearby fields and pastures. (See chapter 11.)  We already know how to do this.


About world hunger: first we need to remember that world hunger is caused not by food shortage but by distribution problems – that is, food is made for profit, and giant corporations have everywhere destroyed subsistence farming and replaced it with products for the world market – causing starvation. The ethanol revolution that Blume proposes includes the desperately needed relocalization, so it is at least consistent with the needed shift in food practices. (Chapter 11 again, plus Lappe's book and website listed below.)


2. Cars and trucks can work well with ethanol, and the conversion is fairly easy.

This is strictly from Blume's work; I didn't evaluate it. Chapters 14-23 and Appendix B are about how and why to convert your car to flex-fuel, including how to fix problems and what to add so it starts in cold weather and so forth. He says the conversion costs about $300, if it's necessary. He also says – a high-compression engine works best, with pure alcohol the engine will last almost forever, and obviously a hybrid is a good idea. Brazil has been running flex-fuel vehicles for decades.


3. We could make a lot of ethanol now, using waste from the Industrial Growth Society, and it would make the energy descent less painful.

When I did the project for my physics class, my focus was on numbers. How much can we make, sustainably? But some of the sources I counted would disappear in a post-industrial world. I am including this section because at this time in 2009, governments are going a little crazy trying to figure how we will run things. Conservation is barely addressed, let alone energy descent. Nuclear and coal both have unacceptable consequences – and both will run out soon enough anyway.  Building ethanol plants – many small ones – could provide a relatively steady source of energy through the transition. Some "feedstocks" will disappear as we wind down.


First, let me mention potential sources for ethanol feedstocks which I was completely unable to number – but they're currently big. Waste food from restaurants, hospitals, cafeterias, and the like. Wasted paper from paper mills, wasted wood from wood plants. Yard wastes. The dumpster at your local grocery store – an increasingly popular food source among the poor. Massive amounts of food thrown away before it ever reaches the stores, because of imperfections. Remember that many things that cannot be used as food are perfectly safe to turn into fuel.   Later we won't have these surpluses, because we will compost or recycle absolutely everything, but right now we have them.


Second are sources which will continue to be available, but I could not find data for calculations. Kudzu. Euonymus. Reed canary grass. Purple loosestrife. Poison ivy, poison oak. Milfoil and other aggressive water plants. Every area has its own problem plants. Harvest them! Then plant some of these – but how many acres? Switchgrass in polyculture: 1500-5000 gal/acre/year; Tipuana tipu in polyculture with a variety of smaller plants, some edible, over 7000; palm tree sap (just the sap!) 2140 gal/acre/year. There are more, but I'm skipping plants grown in monocultures. For a lot more options, see chapter 8.


Third are the three sources I focused on for numbers, selected specifically to restore damaged ecosystems while causing no harm. Present U.S. use of gasoline is 11 million barrels per day or 170 billion gallons per year. Ethanol contains about 30% less energy than alcohol, so we'd need 240 billion gallons per year – to keep being stupid. (2006 numbers; adjust for changes in population and lifestyle.)


Restoring wetlands while treating wastewater. Since Europeans arrived in North America , we've lost over half our wetlands – about 115 million acres. We can't replace them all. Suppose we replaced just 1% of these with constructed wetlands for wastewater treatment – with a cattail/willow or cattail/bamboo polyculture yielding up to 10,000 gal/acre/year – we get 11 billion gallons per year of ethanol, plus oxygen, some wildlife habitat, and absorbing nitrogen and waste. Some of the energy needs to be used for the harvesting process; I don't have numbers for that.


Reclaiming desert by mesquite plantings:

Of the U.S. 2.3 billion acres, 587 million are pasture or range-land, and 40% of those are at risk of desertification. (Unknown: how much already lost to desert.) Imagine half of this land is suitable for mesquite; plant mesquite on those 120 million acres, harvesting mesquite pods for ethanol feedstock, for over 40 billion gallons/year. The mesquite would provide valuable byproducts and would support plantings of pimelon (wild watermelon), prickly pear, and other plants for food, medicine, additional energy, and ecosystem stabilization. First verify that mesquite actually heals desert rather than increasing desertification – which is the majority opinion.


Heal dead zones in the ocean through algae:

Both microalgae and macroalgae (such as kelp) grow rapidly and are good feedstocks for ethanol; a 1970's project at the National Renewable Energy Laboratory found a yield of 5000 gallons/acre/year on microalgae. Giant algae farms are an option. However, I spoke with an inventor who thought he could stop global warming by absorbing carbon dioxide: growing algae on vast areas of ocean, harvesting it for methane, and sequestering excess carbon at the bottom of the ocean. My calculations are based on the more modest idea of using his design to harvest algae only on the ocean’s dead zones near the U.S. , yielding 32 billion gallons/year. Dead zones result from excess carbon dioxide, so this would be a recovery process. Obviously, this scheme should not be taken seriously until safety tests have been run – the ocean is not expendable. I don't think it will ever happen.


So my total was 83 billion gallons – reduced for some reasons, increased for others – out of 240 billion. That's at least a third, barring fatal flaws. (Energy cost of building processing plants.)


4. The sustainable culture in our future would do well to include some ethanol, sustainably produced, to be used for emergency vehicles, buses, trains, community vehicles (shared pickup trucks?), and possibly even in industries such as manufacturing bicycles and recycling metal for tools and such.


There's not too much to say about this. Since producing ethanol gives you a higher quality fertilizer or animal food plus the energy, it seems like a good idea to have some. If we go completely back to the Stone Age, we have 6 billion people and can only support 1 billion; this is a serious problem. Everything is going to be bootstrapped – making solar panels with solar panels, for instance, processing the metal for wind towers with solar, wind, or what? Having sustainable ethanol gives us another option.


Final comments:

Blume also has a list of ways the government could help the move to sustainable ethanol – and the end of Big Oil – mostly funded by ending oil depletion allowances. (Book 6) He has instructions for how to build your ethanol plant, what to grow, how to convert your vehicle, and lots of tables for people who actually want to do that. (For hands-on support or training, you have to go to the website.)


I'm thinking about my bicycle, which I'm riding regularly and getting stronger after decades of inaction. Some day (maybe when I'm 90, maybe sooner) it will need to be replaced. As will my shovels, hammers, knives, tools of all kinds. Nails and screws. Metal could help us protect our forests – which could be in great danger. Energy is going to be scarce. Let's learn ethanol and use it. Let's start now.



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