The increased use of renewable and alternative fuels can result in significant reductions in the use of petroleum-based fuels. By displacing petroleum fuels, many, although not all, of these fuels can provide reductions in greenhouse gas emissions.
To estimate the impacts of increases in renewable and alternative fuels on greenhouse gas emissions, the entire fuel lifecycle including fossil fuel extraction or feedstock growth, fuel production, distribution, and combustion should be accounted for.
There are a variety of lifecycle models and analyses available to perform this type of work, the results presented here are based on one such model, Argonne National Laboratory’s GREET model, and one specific set of assumptions.

By: US Environmental Protection Agency (EPA)

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