Below, we discuss and compare biofuel vs biodiesel vs ethanol.
We briefly outline what each one is, identify the potential differences and similarities between them, and provide a general comparison of them.
Biofuel vs Biodiesel vs Ethanol – Main Differences & Comparison
The main differences between the three might be:
– Biodiesel and ethanol are both types or categories of biofuels
Biofuels can be one of any number of fuel types that are derived from biomass
– Ethanol fuel products contain ethanol (containing organic alcohol (ethyl alcohol)), and is commonly blended with gasoline to make ethanol blends
Ethanol is commonly obtained from fermentation using sugar or starch crops
Ethanol might more commonly be used with gasoline powered vehicles
– Biodiesel is commonly blended with diesel to make diesel blends
Biodiesel is produced from plant or animal oils or fats using transesterification (a chemical reaction process)
Biodiesel might more commonly be used with diesel engine vehicles
What Are Biofuels?
Biofuel is the term used to describe mainly liquid fuels (but sometimes gas too) derived from biomass
What Are Biofuels Used For?
Biofuels are mainly used in transportation as an alternative to petroleum based fuels
Examples Of Biofuels
Biodiesel and ethanol are two of the most commonly produced and consumed biofuels
Biodiesel and ethanol are also both considered as first generation biofuels
There are other biofuels that exist or are in development other than biodiesel and ethanol though
More About Biofuels
Read more about biofuels in this guide
What Is Ethanol?
Also referred to as bioethanol (when these phrases are used in the context of referring to the alternative fuel)
Ethanol is alcohol that is blended with gasoline in different %’s, to make a form of renewable fuel for use in vehicles
How Is Ethanol Made?
Ethanol is first produced via fermentation, whereby glucose and other sugars in biomass (like corn) are converted into ethanol and carbon dioxide
Ethanol is then typically blended with gasoline and refined to make different ethanol blend products
There’s various infographics online that show the step by step process to make ethanol
Cellulosic ethanol is another type of ethanol being developed, and is derived from non edible biomass sources (like trees and grasses)
There’s a range of ethanol blends from E10 or less (such as E5 o E7), through to E100
Using E10 as an example – it contains 10% ethanol, and 90% gasoline
E100 on the other hand is pure ethanol fuel
What Sorts Of Transport Or Vehicles Can Ethanol Be Used In?
Vehicle owners and operators should always check whether their vehicle can accept an ethanol fuel before putting it in their vehicle, as some might be incompatible or cause damage
In general though, E10 can be used in a wider range of internal combustion gasoline engine vehicles
E100 might have more limitations as a fuel, and might need more speciality designed vehicles (with more adjustments to gasoline engines) compared to lower ethanol fuel blends like E10
Some ethanol blends, such as ED95, may also be able to be used in some modified diesel engines
wikipedia.org has a table illustrating these potential required adjustments for some main ethanol blends
How Common Is Ethanol?
eia.gov indicates that: ‘[In 2021, ethanol] accounted for the largest shares of U.S. biofuel production (85%) and consumption (82%)’
energy.gov also indicates that ‘Roughly 97% of gasoline in the United States contains some ethanol’
So, ethanol may be reasonably common in some countries or regions.
What Is Biodiesel?
Biodiesel is a form of diesel fuel that is derived from biomass
How Is Biodiesel Made?
A chemical reaction process called ‘transesterification’ combines animal fat or a vegetable oil of some type with alcohol, to produce ‘a methyl, ethyl or propyl ester’ (although, energy.gov indicates the process involves ‘[… combining] alcohol with vegetable oil, animal fat, or recycled cooking grease’)
This biomass and alcohol derived product is then typically blended with fossil fuel based diesel, and refined to make different biodiesel blend product
The wikipedia.org guide has a far more detailed breakdown of this process, and also describes how biodiesel is made
Biodiesel blends might typically range from B2 to B100
B2 is 98% petrodiesel and 2% biodiesel
B100 is 100% biodiesel (also referred to as a pure biodiesel)
What Sorts Of Transport Or Vehicles Can Biodiesel Be Used In?
Vehicle owners and operators should always check whether their vehicle can accept a biodiesel fuel before putting it in their vehicle, as some might be incompatible or cause damage
Typically, biodiesel can be used with diesel equipment vehicles
Blends with 20% or lower biodiesel might generally be used in diesel engine vehicles with no modifications, or only minor modifications (but this should be confirmed before using)
B100 pure biodiesel might require certain engine modifications or specially designed vehicles
How Common Is Biodiesel?
eia.gov indicates that ‘[In 2021, biodiesel] accounted for the second-largest shares of U.S. biofuel production (11%) and consumption (12%)’
What About Renewable Diesel? (Green Diesel)
The eia.gov and wikipedia.org guides both discuss a developing type of biofuel called renewable diesel, which is also referred to as green diesel
This is a fuel made via hydrocracking
It is made to be chemically similar to petroleum diesel fuel so that it can be used as a ‘drop in’ fuel
It may have several limitations at the moment, with one example being cost competitiveness
7. Various ‘Better Meets Reality’ guides