Since the beginning of the present boom of corn ethanol production in the United States, Brazilian success with its ethanol from sugar cane has been cited as an example of how the USA could get free from its oil imports (mainly from Middle East) by substituting ethanol for gasoline. This would be corn ethanol.
Well, I’m an organic sugar cane farmer and ethanol expert in Brazil. And I think it is my duty to tell my American readers and friends that this comparison is not so simple or straightforward. This would be, indeed, comparing mangoes and apples.
There are two points to consider: First, the immense difference between the two economies and their respective rates of consumption. And, second, the yield and ERoEI differences (net energy, or Energy Returned on Energy Invested) between tropical sugar cane and temperate corn. Let’s first consider Table 1.
Table 1 – Size and consumption differences
| Brazil | United States | Unit | |
|---|---|---|---|
| Population | 184 | 300 | Million inhabitants |
| Total fleet of vehicles | 28 | 230 | Million vehicles |
| Vehicles per inhabitant | 0.15 | 0.77 | Vehicles/inhabitant |
| Gasoline consumption | 4.0 (thanks to ethanol) | 140 | Billion gallons/year |
| Gasoline production | 5.24 (exports exceeding) | 119.5 (needs imports) | Billion barrels/year |
| Oil consumption | 1.8 | 21 | Million bbl/day |
| Oil production | 1.84 | 8.6 | Million bbl/day |
| Oil imports | 0 (imports 2% as diesel) | 12.4 | Million bbl/day |
| Ethanol consumption | 4.00 | 5.86 (fuel) | Billion gallons/yr |
| Ethanol production | 4.80 | 4.85 | Billion gallons/yr |
| Ethanol exports | 0.80 | 0 | Billion gallons/yr |
| Gasoline replaced | 50% | < 4% | (by ethanol) |
Having a population that is 61% of the USA’s population, Brazil has a fleet of vehicles that is only 12% of the total American fleet. And a gasoline consumption that is only 2.9% (yes, this is really less than 3%!) of USA’s gasoline consumption.
This very large difference arises from seven factors:
First, being the richest country in the world, the USA has a number of cars that far exceeds the total number of licensed drivers, with almost 0.8 vehicles per person. Brazil, a much more modest country, has only 20% of that impressive rate.
Second, the average American vehicle is larger, heavier and less efficient (21 miles/gallon), with a large number of SUV’s and light trucks being preferred by families. The average car produced in Brazil (at 17 factories) is smaller, with predominant European and Asian influence in car design, a large number of cars being compact and obtaining 40 miles/gallon (gasoline).
Third, by the end of 2006 ethanol will supply 50% of all otherwise needed gasoline. Without fuel ethanol, Brazil would need now 8 billion gallons/year of gasoline, still a bargain when compared to the USA’s 140 billion gallons/year.
Four: there’s no suburban commuting in Brazil. Urban development did not give rise to an affluent class living in distant suburbia and commuting, for working and shopping, tens of miles a day. In Brazil, suburbia is synonymous to poverty; people commute by train, bus and subway to their working places.
Five: 80% of all new cars are now flex-fuel, running on pure gasoline, pure ethanol or any mix of them.
Six: Brazil started to produce and distribute fuel ethanol, for replacing gasoline, in 1975. That’s more than 30 years experience, so 100% of all gas stations, in cities or roads, have ethanol pumps and tanks.
Seven: Brazilian ethanol, produced from sugar cane, is much cheaper that Brazilian gasoline distillated from locally extracted oil. Most of the year, its price is around 55% of gasoline price. In order to be economic, the ethanol price must be at least 70% lower than the price for gasoline.
Self sufficiency in Brazil
To reach a point where all gasoline is replaced with ethanol would be very easy for Brazil and not so desirable for Petrobras, its State-controlled major gasoline producer and exporter. The present sugar cane cultivated area, dedicated to ethanol production and permitting a 50% replacement of gasoline, is 3 million hectares (7.4 million acres).
That is less than 1% of our total arable land. In order to double ethanol production, there is no need to exactly double the planted area, as a steady increase of 3% in yield has been achieved every year in agricultural plus industrial operations, over the last few decades. In 1975, ethanol yield was 375 gallons/acre/year. In 2006 it is reaching a new mark of 870 gallons/acre/year. And organic sugar cane has an even higher yield.
Available land for sugar cane expansion (considering only areas no longer needed for pasture land in Southeast and Center regions, best suited for sugar cane): 18 million ha (44.5 million acres). So it is really very easy for Brazil to replace gasoline with ethanol. But this is not the same for the United States.
USA
To replace all its gasoline (140 bln gal/yr) with ethanol from corn, the USA would need, at present yields of 400 gallons/acre/year, almost 350 million acres of dedicated corn, not including any corn for humans or animal feed. But all the present USA area cultivated with corn is only 75 million acres (FAO, Faostat, 2005)
It would require 297.5 million acres for E 85. Or 35 million acres for E10.
At present moment, USA needs almost 400 000 bbl/day of ethanol but produces 300 000+ bbl/day. This is just to replace MTBE, as required by law. So, imports and new plants are supposed to fill the gap.
But corn and sugar cane are very different
Sugar cane is a semi-perennial culture (6-7 years cycle) that needs far fewer nutrients (fixing nitrogen from air through Gluconacetobacter diazotrophicus, for example) than corn. It is the less soil-eroding large crop in Brazil because soil remains covered most of the year or all year round. Sugar cane in Brazil is not irrigated.
All energy for the industrial process comes from bagasse burned in high pressure boilers, providing all thermal, mechanical and electrical energy needed, with at least 10% surplus electrical energy sold to the grid. Corn needs natural gas or fuel oil and electricity from the grid to supply its process-energy demands in the factory.
Ethanol yield (gallons/acre) for sugar cane under good tropical conditions is double that for corn. For all those reasons, sugar cane ethanol is seven times more energy efficient; its net energy, expressed as ERoEI, is 9:1 while corn ethanol has an ERoEI of only 1.3:1.
Conclusions
So, apart from considering whether USA corn ethanol is an energy efficient product or not (what I’m not doing here), one thing must be stressed: sugar cane ethanol from Brazil is NOT a realistic target or a comparable model for USA ethanol from corn. It is very easy to replace all gasoline when you would only need 8 billion gallons per year and you have a generous plant that thrives rain-fed under tropical conditions, occupying less than 1% of a country’s arable land, to produce alcohol to replace 50% of all that gasoline. However, this cannot be extrapolated for USA’s conditions, neither for corn, not even for sugar cane in Southern states. So, realistically, let’s understand that sugar cane ethanol in Brazil is mangoes and corn ethanol in USA is apples.
Milton Maciel, an organic farmer, consultant and author of more than 10 books, is a former Secretary of Agriculture in Alagoas State, Northeast Brazil. He specializes in soil regeneration, organic sugar cane and alcohol production and is a designer for Brazilian Zero Oil Farms project. Milton will be presenting more details about this comparison during the ASPO-USA conference at Boston University on October 26th.
