Potenciales y Viabilidad del Uso de Bioetanol y Biodiesel para el ...

Potenciales y Viabilidad del Uso de Bioetanol y Biodiesel para el Transporte en México (SENER-BID-GTZ)
Task 7: Rationales, drivers and barriers for fuel ethanol and ETBE market introduction
automation) would lead to lower figures. Nevertheless, job creation (at relatively low
investment) could be one of the most important social contributions of the program.
If priority is given to large scale sugar cane expansion in pasture and marginal lands, regional
development in new areas would take place, creating jobs and promoting social infrastructures
where few existed before.
Reviewing and revising creatively the existing social compact between sugar cane growers
and mills may offer an opportunity to maintain for the current beneficiaries and to expand
social benefits for the rural workers not enjoying them presently. It is not a trivial assignment.
It requires ingenuity and creativity, but without progress in this area the social cost of fuel
ethanol in Mexico may be too large for the key stakeholders to achieve a consensus in support
of an ethanol program in the country.
Environmental
Sugar cane based ethanol is far superior to other feed stocks in terms of net energy ratio.
Sugarcane, in contrast with corn and other feed stocks, generates its own process fuel – the
bagasse. If expertly designed a distillery (and sugar mill) can supply all its energy
requirements and export surplus electricity. This translates into the highest CO 2 mitigation
values among competing feed stocks. Hence, sugar cane ethanol may give a substantial
contribution for reducing greenhouse gas emissions.
Crop wastes such as leaves and trash can also be added to bagasse to generate even more
surplus energy. The main liquid waste from ethanol distilleries – stillage or vinasse – can be a
source of fertilization-irrigation for its potassium content and degree of dilution. Sugar cane
land is usually rotated with nitrogen fixing plants such as peanuts, which enriches and
preserves soil quality.
When used as a fuel, ethanol requires the gasoline blend stock to be free of light hydrocarbons,
to keep vapor pressure of the blend within specification and limit evaporative losses of volatile
organic compounds. Burning ethanol in a gasoline blend decreases the emissions of CO and
unburned hydrocarbons due to fuller combustion. It may or may not increase NO x emissions.
Nevertheless, the NO x emission levels in California after the adoption of 5.7% v/v ethanol
blends has not increased. Aldehyde emissions do increase, especially of the less harmful
acetaldehyde, but the emission level is well under the limits established by the World Health
Organization.
Food security
The development of sugar cane agriculture geared towards ethanol is likely to improve the
competitiveness of sugar making in Mexico and allow it to penetrate the US market, which
will open to Mexican sugar by 2008. In time, it may also help Mexico fight off the fructose
invasion from the US. It may also have a positive impact in Mexican agriculture in general,
improving food security.
The adoption of sugar cane juice as the major source of fuel ethanol in Mexico leads to the
lowest area requirements of all other alternative feed stocks. Regarding food security, this is a
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