Background, aim, and scope Algae biomass has great
promise as a sustainable alternative to conventional
transportation fuels. In this study, a well-to-pump life
cycle assessment (LCA) was performed to investigate
the overall sustainability and net energy balance of an
algal biodiesel process. The goal of this LCA was to
provide baseline information for the algae biodiesel
process.
Materials and methods The functional unit was
1,000 MJ of energy from algal biodiesel using existing
technology. Systematic boundary identification was
performed using relative mass, energy, and economic
value method using a 5% cutoff value. Primary data
for this study were obtained from The USLCI database
and the Greenhouse Gases, Regulated Emissions and
Energy use in Transportation model. Carbohydrates
in coproducts from algae biodiesel production were
assumed to displace corn as a feedstock for ethanol
production.
Results and discussion For every 24 kg of algal biodiesel
produced (1,000 MJ algae biodiesel), 34 kg coproducts
are also produced. Total energy input without
solar drying is 3,292 and 6,194 MJ for the process