3. Results and discussion
3.1. Results
3.1.1. Energy
The energy inputs and outputs for all 20 cases are shown in Fig. 2. The
energy impacts assigned to each contribution are listed in TableD-3 of the
SI. Case 1 incorporates inefficientmethods that yield high energy requirements
and a low-nitrogen growth setting with lower productivity than
the high-nitrogen cases. Case 2 improves upon Case 1 by usingmore efficient
technologies and Case 3 applies a high-nitrogen growth setting with
higher yields, further improving the EROI with respect to Case 1. Case 4
(Desmodesmus sp.) has a greater oil content than Case 3 (Staurosira sp.)
and no silicon requirement, but the EROI is less than Case 3 because
there is less animal feed produced, which receives a large displacement