World Energy Outlook 2006

Czech Republic
Ethanol
Figure 14.1: Share of Biofuels in Total Road-Fuel Consumption
in Energy Terms by Country, 2004
Canada
Italy
France
World
United States
Germany
Sweden
Cuba
Brazil
0% 2% 4% 6% 8% 10% 12% 14%
Sources: F.O.Licht (2006) and IEA databases.
Conventional ethanol production technology involves fermenting sugar
obtained directly from sugar cane or beet, or indirectly from the conversion of
the starch contained in cereals. The ethanol produced is then distilled to
produce a fuel-grade liquid. In OECD countries, most ethanol is produced
from starchy crops like corn, wheat and barley, but ethanol can also be made
from potatoes and cassava, or directly from sugar cane and sugar beet. In
tropical countries like Brazil, ethanol is derived entirely from sugar cane.
Starchy crops first have to be converted to sugar in a high-temperature
enzymatic process. The sugar produced in this process or obtained directly
from sugar crops is then fermented into alcohol using yeasts and other
microbes. The grain-to-ethanol process yields several by-products, including
protein-rich animal feed. By-products reduce the overall cost of ethanol, as well
as the net greenhouse-gas emissions associated with its production, where crop
residues such as straw or bagasse are used to provide heat and power for the
ethanol production process.
Efforts to introduce ethanol into the market for road-transport fuels for sparkignition
engines have focused on low-percentage blends, such as ethanol E10,
a 10% ethanol and 90% gasoline blend (known as gasohol in Brazil and the
United States). Such blends, which are already marketed in many countries, do
388 World Energy Outlook 2006 - FOCUS ON KEY TOPICS