Reality check #1: Although everyone knows that biodiesel pollutes the air less than conventional diesel, almost no one knows that a car running on soybean-based biodiesel pollutes the air worse than one running on gasoline. In other words, a soybean based biodiesel powered car would have a worse EPA air pollution rating than an "equivalent" gasoline car.

If you stand next to a Golf or Jetta burning 100% biodiesel for a few seconds you will soon notice the strong odor of burned vegetable oil, which is mother nature's way of signaling that you are drawing into your lungs considerable amounts of soot--particulate matter released from the combustion of organic compounds. There are over 20 gasoline models today that are considered near-zero emissions. Certainly, no biodiesel powered car pollutes less than one of these. Go here for notes, sources, and further discussion.

Reality Check #2: Because it has a better net energy balance, soy-based biodiesel is assumed by many to be a better choice than corn-based ethanol. But it isn't that simple. It takes almost 4 acres of soybeans to produce the same gas mileage of biofuel as a single acre of corn. Ethanol may be energy intensive to produce, but soy-based biodiesel is land intensive. Soy-based biodiesel also receives twice as much government subsidization as ethanol in addition to polluting the air much worse at the tail pipe. Corn-based ethanol is a poor choice for a biofuel for several reasons and so is soy-based biodiesel, for different, but related reasons. Go here for notes and calculations.

Reality Check #3: Soy-based biodiesel releases more CO2 than is generally thought. When biodiesel first made its appearance, it was touted as being carbon neutral. You can Google that term today and see that the misconception is alive and well.  This study shows that it reduces CO2 by only 41% (you will release 59 pounds of carbon for every 100 pounds combusted). Go here for notes, sources, and more discussion. But this may all be irrelevant in light of a new peer reviewed study in Science has concluded that biofuels are overall worse for global warming than petroleum.

Reality Check #4: Soy-based biodiesel cannot make a dent in America's contribution to global warming. How much is a dent? I'll let you decide. We can reduce our CO2 emissions less than one percent using all of our reserve farmland to grow soybeans. Reducing all miles driven in the U.S. by just 3% or increasing average U.S. car fleet gas mileage 3%, will have more impact than burning 100% biodiesel made from soybeans grown on all of our reserve farmland carbon sinks.

Reality Check #5: Soy-based biodiesel is not a fully renewable resource. Environmentalists have been pointing out the unsustainable nature of industrial agriculture for many years now. Industrial crops consume billions of tons of water, pesticides, insecticides, and herbicides. Anyone who drives a car using 100% biodiesel made from soybeans is usurping 7 football fields worth (9 acres) of vegetable oil annually to feed their car. That is almost an acre a month. To get a feel for the immensity of  7 football fields, go stand in the middle of just one.

Ever hear of a thing called an ecological footprint test? It provides a rough feel for how much of the planet you are claiming as your own. The average American is purported to have a score of about 24 acres, which as you might guess is the highest in the world. Go ahead and take it (keep in mind that the average American drives 230 miles per week). The average American would have to add all but a few of those 9 acres mentioned earlier to the mobility part of their test score if they drove a car that uses 100% biodiesel made from soybeans, which would increase their score from 24 acres to about 38 acres, which is an increase of over 50%. Go here to see those references and check the math.

Vegetarians who use biodiesel made from soybeans are usurping 5 times more land for their cars than their beef eating counterparts are for their cows. Go here to see notes and calculations.

Reality Check #6: Biodiesel does not smell like popcorn or french fries (it sure can't smell like both). Forget the fact that you don't cook popcorn in deep fryers, very ,very little biodiesel is made from french fry grease. Since the vast majority of biodiesel is made from virgin vegetable oils, it actually smells like incinerated vegetable oil, which is exactly what it is. The odor is very noticeable and to many, unpleasant, unless you like the smell of a grease fire. This myth creates a positive image and is repeated daily by the lay press. Not that it matters but it is a good example of the hype surrounding this fuel.

Reality Check #7: Since it is not physically possible to grow enough soybeans to replace more than a percent or two of our liquid fuels, it cannot lessen our dependence on foreign oil to a degree that would be meaningful. Cheap biodiesel coming into our ports grown on cleared rainforests will simply switch which kind of foreign oil we buy. If you can only grow 1.5% of your fuel supply, then, at best, only 1.5% of it is ostensibly renewable, leaving 98.5% that is not. To blend 2% biodiesel, into our existing diesel supply  would take one-fourth of current U.S. soybean production. Go here to see those references and check the math.

Reality Check #8: A small percentage of our biodiesel is made from waste. Collecting waste oil from thousands of point sources makes large-scale production with waste oil more expensive. That is why major producers use virgin oils. Using biodiesel made from waste is a good thing, using biodiesel made from soybeans is not. Click here for an interesting audio report from NPR titled Grease Wars.

Reality Check #9: Soy-based biodiesel is rarely a locally grown product (similar to local produce). Almost all of the oil for the major coastal refiners comes from thousands of miles away and some of it is even coming from South America.

Reality Check #10: Biodiesel competes with food for cropland. Soy oil is a valuable commodity traded on the futures market:

"Typically, the value of soy oil accounts for 38 to 40 percent of the soybean crush. But the energy boom has pushed the value of soy oil to 41 and 42 percent."

Soy oil is a byproduct, which is not the same as a waste product. The price of the oil may rise with demand until supply catches up, making the soy meal the by product. Likewise, the price of soy meal may go down with an increase in supply unless an increase in demand can be developed in parallel. The bottom line: we will have to grow more soybeans to meet the demand for biodiesel. Where would those other users now go for their oil? If food producers have to turn to palm oil you have just pushed the problem from our shores to Orangutan habitat. If they have to buy it from South America, you are destroying the Amazon.

A similar argument can be made against corn ethanol because it takes 56 pounds of corn kernels to produce 2.8 gallons of ethanol, 11.4 pounds of distiller's grain., 3 pounds of Glutan meal, and 1.6 pounds of corn oil. So,  56 - 11.4 -3 -1.6 = 40 pounds of corn lost that cannot feed people (or the cows that people eat). In other words, about 70 percent of a bushel of corn is lost to the food chain when you use it to make ethanol.

The next time you hear someone say, "The government pays farmers not to grow more food!" Explain to them that this is called the Conservation Reserve Program (or CRP). Essentially, the government rents marginal farmland (wetlands, hilly land, etc) from farmers for something like $40 an acre to keep it out of production, to keep farmers from trying to make more money by planting more crops (thus depressing prices). Although not part of the original intent, this land over the years has returned to the wild and is acting as a giant carbon sink soaking up 15 to 30 percent of America's CO2. It has also provided a great deal of wildlife habitat. By putting all of this back under the plow, we could only fuel 6% more of our cars while destroying what has become a giant carbon sink.

Few people understand the definition of crop surplus. It does not mean that extra beans are dumped in landfills. They all get sold. A surplus means that the sellers are not getting an acceptable price for the grain they have produced, so the grain gets exported where it is subject to free market sales competition on the world market. Biofuels are gobbling up our export grains. Higher food prices affect the poor much worse than you or me because most of their income goes to food, whereas you and I spend next to nothing on food. There is no dumping of corn or soybeans into landfills. All corn and soybeans grown all go into the human food chain in some form someplace in the world… or into biofuel. The The UN's special rapporteur for food has recently called for a five-year moratorium on all government targets and incentives for biofuel, calling biofuels made from food crops  "a crime against humanity". The UN Food and Agriculture Organization just announced the lowest global food reserves in 25 years.

It takes almost 4 acres of soybeans to produce the same energy as an acre of corn. The land needed to grow corn is beginning to expand along with the demand for ethanol. The land needed to do that will have to come out of our conservation reserve land which has been serving as a carbon sink. Go here for notes.

Reality Check #11: Supporting the use of soy-based biodiesel (buying it) will not promote more efficient means of producing biodiesel in the future. Making biodiesel out of soybeans may actually hinder the development of future improvements in biofuel technology. In short, you cannot use the same infrastructure (bean crushing and drying facilities and the railroads leading to them) to produce oil from something like algae or Sundiesel. The same can be said for making ethanol out of switch grass instead of corn. You would have to tear all of that infrastructure down and start all over because without further massive subsidization, soy and corn will not be competitive. Can you imagine politicians from States that have invested billions in infrastructure to make biodiesel from soybeans actually voting in a manner that would dismantle that infrastructure? The bigger the soybean-based biodiesel industry gets, the harder it will be to bring down. Agribusiness is already the biggest welfare sink  in the country, receiving tens of billions of dollars in subsidies thanks to pork barrel politics.

I am often admonished not to throw the baby out with the bath water. That analogy is meant to imply that if the good outweighs the bad, you shouldn't throw out the good just to get rid of what is bad. It's a poor analogy for biodiesel made from soybeans because this product is clearly bad for the environment in every respect but a very slight reduction in U.S. CO2 production (a potential of less than half a percent). In other words, that isn't a baby floating in the bath water.

Reality Check # 12: We should not jump to food based biofuels to help rid ourselves of an oil addiction. The only way to end an addiction is to stop using whatever you are addicted to. In this case, it is liquid fuel. Most people could really care less about what fuel they burn as long as it is the lowest cost fuel. That is why our government is subsidizing soy-based biodiesel to the tune of a dollar a gallon, because most will just buy the cheaper fuel, whatever that is. See related check # 11. The calculations supporting check #7 show we cannot grow enough biofuels within our own borders to become even remotely free of imported oil. We will simply become dependent on other sources of oil if we do not find ways to use much less liquid fuel.

Reality Check # 13: We should not rush to embrace technologies that produce less CO2 that are also destructive to our natural ecosystems. The whole point of reducing CO2 is to stop the destruction of our natural ecosystems. We do not want to reduce CO2 at any cost.

Reality Check #14: There is no one answer to our energy concerns and the hard reality is that we don't yet have enough answers. From this engineer's perspective, I am betting on plug-in hybrids in the near term, not as the answer, but as one of the important pieces to the puzzle. Go here for an in-depth discussion of this and other options.

Reality Check #15 If soybean based biodiesel is a net loss when it comes to environmental degradation, then what should I do as an individual to reduce global warming? The following is not a comprehensive list by any means but covers some big ticket items. Aside from buying biodiesel only from refineries that can prove to you that it is made solely from waste veggie oil, you can:

1) Support legislation that mandates higher gas mileage. Increasing average U.S. car fleet gas mileage just 3% would reduce U. S. fuel consumption more than using all the soy-based biodiesel grown on all of our conservation reserve carbon sinks (see check #4). Increasing our fleet average 10% would save three times as much and would use not a single bean. Increasing a 30 MPG car's mileage 3% makes it a 31 MPG car.
2) As an individual, you can purchase the highest gas mileage car that fits your needs, and/or share a ride when feasible (every time you share a ride you double your gas mileage per person).
3) Support research into more efficient ways to produce biofuels (algae, cellulosic methods etc).
4) Walk and bike instead of drive when feasible.
5) Resist the urge to jump on new schemes before debate flushes out their pros and cons. There are many ideas coming down the road that have great potential to help with global warming and our liquid fuel concerns. Soy-based biodiesel is not one of them. Stop supporting any food crop-based biodiesel. Don't give anyone the incentive to grow 9 acres of soybeans  to feed to your car or to build an infrastructure for  refineries that will prove difficult to remove (or to stop subsidizing) when better technology arrives.
6) Support legislation for liquid fuel taxes that also redistribute that tax revenue back to the public with income tax reductions (or some other means). A tax scheme like that will stimulate the free market to conserve fuel and develop fuel efficient technology without increasing the overall financial burden of the taxpayer.

Reality Check #16: Even though most of our electricity still comes from coal-fired power plants, plug-in cars would still significantly reduce CO2 emissions (up to 65% depending on assumptions), air pollution, and liquid fuel use. Power plants have reserve capacity to meet peak demands. For example, more water is released in the mornings from the Grand Coulee dam to meet higher demands of daylight hours. Less is released when the power is not needed. More water could be released at night to charge electric cars. Using the unused capacity of power plants to charge cars at night would be ideal.
Of course, there is a limit as to how much water is available from year to year, and building more dams is not something I would support. Ultimately, we need CO2 free technology and better efficiency. Go here to see calculations and more discussion.

Reality Check #17:  Biofuels will end poverty in third world nations. On paper, this is hard to argue with. In reality, biofuels in third world countries are turning the poor into farm hand wage slaves while displacing locals and destroying biodiversity all at the same time as seen here in Colombia, Paraguay, and Uganda.