in different ratios in order to be utilized in
diesel engines and to reduce petroleum diesel
consumption. These benefits of biodiesel make
it to be a suitable alternative fuel. The general
method to produce biodiesel is by transesterification
reaction, which has vegetable oil and
methanol as reactants and which uses a catalyst.
Glycerol and fatty acid alkyl ester (biodiesel)
are the by-product and the main product of the
reaction, respectively. The environmental impact
of biodiesel production has been studied by
several researchers.
Life cycle assessment of biodiesel
production was studied by Varanda et al. [4].
The study focused on four simulated processes
of biodiesel production from virgin oils and two
simulated processes of biodiesel production
from waste cooking oils. In what concerns life
cycle assessment, processes using waste
cooking oils have lower overall environmental
impacts than the processes using virgin oils.
Life cycle of algae production was studied by
Clarens et al. [5] focusing on environmental
impacts by comparing with switchgrass,
canola, and corn farming. The environmental
impacts of these crops have lower impacts than
algae in energy use, greenhouse gas emissions,
and water. Algae can convert to biofuelsbiogas,
biodiesel, bioethanol, biohydrogen,
and microalgae gasification-studied by Singh
and Olsen [6]. Comprehensive life cycle
assessment of algal biofuels illustrating
environmental benefits and impacts can be a
tool for guiding technology development as
well as for policy decisions. Algae-based
biodiesel production was studied by Lardon
et al. [7], considering the environmental impacts.
The outcome confirms the potential of microalgae
as an energy source but highlights the imperative