In ascertaining whether the microalgal biodiesel production process is carbon neu­tral or carbon negative (absorbs carbon dioxide) or carbon positive (releases carbon dioxide) a life cycle assessment (LCA) is carried out. The LCA is based on ISO 14,040 standards [11].

1.7.3 Life Cycle Assessment: Goal and Scope

The LCA is based on a solid understanding of the GHG neutrality of the process. The LCA will be conducted on the entire process, from the cultivation stage to the final processing stage (gate-to-gate assessment).

1.7.4 Life Cycle Assessment: System Boundary

The LCA system boundary is based on the physical boundary of the entire plant. Basically, a cordon is placed around the entire plant and an audit is performed on the inflow and outflow of GHGs and any energy input and output. However, as the process is developed stage-wise, the boundary is enclosed around the individual stages to simplify the audit. By including all possible factors which may affect the carbon neutrality of the process, the goal is to ensure the carbon audit is a true rep­resentation of the actual emissions from the process. Conducting such an extensive and in-depth audit allows an accurate analysis of whether such a process is feasible in reducing the GHG emissions.