By Alvaro Vicente Lopez
On which we can ask ourselves: is this the solution to the production of alternative energy to oil? What is Biodiesel? As the ASTM (American Society for Testing and Materials) indicates, Biodiesel is "the long-chain monoalkyl ester of fatty acids derived from renewable resources, such as vegetable oils or animal fats, for use in Diesel engines."
As indicated in the previous definition, mainly the origin of biodiesel is vegetable, and this origin is referred to as one of the fuel's own advantages, since it generates less CO2 during its combustion than the one that plants absorb for their growth. (closed CO2 cycle) 2.
In addition, a series of related advantages are added or indicated: it is produced from renewable raw materials; contains virtually no sulfur; avoids SOx emissions (acid rain or greenhouse effect); It does not contain benzene or other carcinogenic aromatic substances; it is easily biodegradable; It is not a dangerous good (the flash point is above 110º C).
What is a panacea? The panacea is a mythical medicine that cures all diseases or even prolongs life indefinitely.
It was sought after by alchemists for centuries, especially in the Middle Ages.
The word panacea comes from the Greek word panakos and means "remedy for everything." Therefore, according to the definition of Biodiesel and Panacea respectively, could this type of fuel be considered as the remedy for the decrease in the amount of greenhouse gases and as the potential replacement of fossil fuels in the process of extinction?; In this sense, some elements are presented that allow us to briefly raise this discussion, and leave open some questions about this panacea ?: Energy Return Rate From the reading of the book Development and Ecopolitics by Tomas Buch, the concept of “rate of energy return "TRE or ERoEI" Energy Returned on Energy Invested ", simply defining this rate is the relationship between the energy obtained with respect to the energy invested to obtain it, if this value is greater than 1 it implies that a profit was produced energy (for example, it is not the same to pump oil at a depth of one hundred meters than at a depth of five hundred meters, at the same production, the energy invested is greater in the latter case and exploitation may become inconvenient).
So the question that arises is: is biodiesel energetically viable? What is the TRE of Biodiesel? A study by Cornell University and the University of California-Berkeley3 indicates values (related between the energy obtained and energy expenditure) for soybeans lower than one in relation to the TRE, the study indicates that "for soybeans a 27% more fossil energy in relation to the amount of fuel obtained ”in the case of sunflower“ 118% more fossil energy is required, in relation to the amount of fuel produced ”, these data include the amount of fuel required for the entire production process, from sowing to obtaining biodiesel, and also includes all energy expenditure derived from fertilizers, pesticides and required inputs.
Other studies indicate higher ERT values for soybeans against the 0.78 defined by Pimentel Patzek (2005), these being: 2.09, Carraretto, et al. (2004); 2.5, Ahmed, et al. (1994); 3.22, Sheehan, et al. (1998); 3.67 Hill, et al. (2006) and 4.56 Pradhan, et al. (2009) .4 The variability of these values leads us to rethink the calculation methodologies, since, for example, one of the considerations is that the waste resulting from the process (which they use as animal feed) enters the output of the equation, which considerably increases the value of it (will this be an adequate consideration?).
In Argentina these calculated values are between 1.19 and 4.67 according to the different variables considered (climatic, type of soil, production system, etc). Cultivated area To achieve the biodiesel yields presented at the beginning of the note, approximately 667,000 hectares should be cultivated with soybean cultivation (if we take this crop as a base), an area that would not be used for the production of food for human beings on the one hand and on the other hand, the total production of this fuel covers a minimum part of the demand for fossil fuels, replacing only up to 10% in diesel fuels (since a higher percentage would affect engines).
It is noteworthy that allocating land for the production of biodiesel generates, in the first place, a greater demand for productive land, which induces an advance on marginal lands, affecting native forests in some regions of Argentina. In addition, these marginal lands have a lower productivity, generating Energy Return Rates with values lower than 1; secondly, when marginal lands are affected by unfavorable climatic factors and do not produce the expected yields, they are abandoned with the consequent loss of biodiversity.
The land destined for the production of Biodiesel, competes, with the production of food since the final destination of its production is modified.
By way of illustration, we can indicate that with the cultivated area for the production of Biodiesel, approximately 4 million people could be fed for one year (6 people per ha). Not only is the number of people who stop feeding important, but also that in the long term the increase in biodiesel production would lead to a reduction in the area used for food production and the consequent increase in the prices of food. themselves (as indicated by the economic laws of supply and demand) and in turn would leave a larger population excluded from much-needed food.
In conclusion, is biodiesel a panacea ?: No, if for its development it competes with food production, advancing on marginal lands, reducing the availability of food and increasing its value. No, if the energy return rates are low or close to one, for which a clear methodology and criteria must be defined in their determination.
Finally, it is necessary to move forward with the search for other alternative energies that are viable and environmentally sustainable, as well as creating funds from non-renewable resources to research, create and promote these energies.
Another aspect to consider is that we must rethink and modify the cultural issues that lead us to over-exploitation of non-renewable resources and abuse in the use of energy (energy that in countries like Argentina is very economical), in order to extend these resources and work on the search for viable alternatives.
The time is now, the historical possibility to begin this type of change is today, unless we are like the toad in the pot that heats up slowly without it noticing, and ...