Abstract
Biofuels, just like fossil fuels, are also associated
with various environmental impacts along the productionconsumption
chain. Those impacts need to be attributed to
different products, as biofuel production generally yields one
or more co-products, like animal fodder or soymeal, or may be
a co-product of some other, higher-valued process, like bagasse
from sugar cane for heat or electricity production. Life cycle
assessments impacts of biofuels are usually studied in a
comparative manner, in order to analyse which alternative
amongst fossil or bio-based options has the lesser
environmental burden.The inventory analysis shows that the
inputs and outputs of the farming unit process are sensitive to
the type of crop and region of produce. Water usage is a highly
variable parameter, which emphasises the importance of
rainfall and irrigation to the overall burden of the biodiesel
system on water resources. Crop yields may differ by a factor
of two, which is a significant difference in terms of land and
non-renewable energy resources requirements. The oil and
meal/cake content of the seed proves to be the most important
parameter that influences the initial unit processes of the value
chains.