The Road to Energy Independence
We've included some high-level information about biofuels below to give you a better understanding of how advanced biofuels,
such as
butanol and
isobutanol, fit into the larger picture.
Definition
Biofuels can be defined as solid, liquid, or gas fuels derived from biological, renewable sources called biomass. Some examples of biomass that can be
used to produce biofuels today include sugar crops, corn grains, grain byproducts, oil seed crops, trees and grasses.
How Biofuels are Made
To create biofuels from biomass, the biomass must go through the appropriate chemical reaction, also called an energy conversion route. For example, to create
alcohol-based, advanced biofuels like butanol and isobutanol, the biomass must first be fermented (like beer or wine) using a microorganism to produce the crude biofuel
product. The crude product is then refined to make the fuel and chemical products.
| FUEL |
Energy Density |
Air-FUEL Ratio |
Specific Energy |
Heat of Vaporization |
| Gasoline |
32.0 MJ/L |
14.6 |
2.9 MJ/kg air |
0.36 MJ/kg |
| Butanol |
29.2 MJ/L |
11.2 |
3.2 MJ/kg air |
0.43 MJ/kg |
| Ethanol |
19.6 MJ/L |
9.0 |
3.0 MJ/kg air |
0.92 MJ/kg |
| Methanol |
16.0 MJ/L |
6.5 |
3.1 MJ/kg air |
1.20 MJ/kg |