Biofuel energy
Biomass is renewable organic material that comes from plants and animals. Biomass can be burnt directly for heat or converted to liquid and gaseous fuels through various processes 1. These fuels are known as biofuels. They are mainly used to help meet transportation fuel needs2, but also used for heating and electricity generation.
Examples of biomass include:
Wood and wood processing waste
Agricultural crops and waste materials
Animal manure and human sewage for producing biogas (renewable natural gas)
The liquid biofuel in greatest production is ethanol (ethyl alcohol), which is made by fermenting starch or sugar. Brazil and the United States are among the leading producers of ethanol 3. In the United States, ethanol biofuel is made primarily from corn (maize) grain. It is typically blended4 with gasoline to produce “gasohol”, which is a fuel that is 10 percent ethanol (E10). In Brazil, ethanol biofuel is made primarily from sugarcane, and it is commonly used as a 100-percent-ethanol fuel or in gasoline blends containing 85 percent ethanol (E85).
The second most common liquid biofuel is biodiesel, which is made primarily from oily plants (such as the soybean or oil palm) and to a lesser extent from other oily sources (such as waste cooking fat from restaurant deep-frying). Biodiesel is used in diesel engines and usually blended with petroleum diesel fuel in various percentages. The most common biodiesel blends are B20, which ranges from 6% to 20% biodiesel blended with petroleum diesel and B5 (a biodiesel blend of 5% biodiesel, 95% diesel) which is also commonly used in fleet vehicles.
In 2023, the leading biofuel producer in the world was the United States, with production amounting to 1,795 petajoules. Brazil and Indonesia ranked second and third, with figures at roughly 1,016 and 433 petajoules, respectively 5.
Despite Africa having suitable resources for the growth of bioenergy crops, biofuel production is still very low in the region. In their review of the potential markets and policies for sustainable liquid biofuel production in Eastern Africa, Miftah and Mutta (2024) note that liquid biofuel production has been restricted by various factors. The first issue is lack of a market, as biofuel trade is mainly driven by countries that have put policies in place to reduce emissions and tackle volatile fuel prices. The second issue pointed out in their paper is institutional weaknesses such as corruption and land-use conflicts that hinder the possibility to coordinate liquid biofuel production. They highlight the need to have appropriate policy measures6 in order to determine local land use, select the appropriate type of bioenergy crops, and biofuel processing types and scales. They conclude that small and large scale biofuel projects are required to include biofuel production in the conventional agricultural farming practices.
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References
Footnotes
Blended fuels are mixtures of different fuel types designed to achieve specific objectives such as emission reduction or enhanced performance. Common types include ethanol-gasoline blends like E10 and E85 and biodiesel blends like B5 or B20.↩︎
A policy describes the principles that an institution applies in various situations. A policy measure is a specific thing that an institution does to carry out the policy.↩︎