Life cycle assessment (LCA) is a burgeoning field of study which seeks to understand the environmental impacts of our choice in systems, processes, products or activities even before we implement them. As the name insinuates, life cycle assessment looks at environmental impacts over the life of a product or process, from raw material production through different life stages and disposal. There are four basic steps to life cycle assessment. Step 1 is to define a goal and scope to understand what system is being studied and how results between different systems are equated (i.e., impacts per capita, impacts per gallon of water, etc.) Step 2 is to perform the life cycle inventory by quantifying what inputs of water, energy and raw materials are required and what emissions or damages are released to air, water and land. During step 3, an impact assessment method is applied that groups together emissions to determine their overall effect on different categories. Those categories can range from climate change potential to land destruction to human toxicity. The final step in LCA is interpretation of the assessment and understanding why the trends exist.
ASU is at the forefront of LCA research, and I was fortunate enough to take the Life Cycle Assessment for Civil Systems class with Dr. Mikhail Chester. This class allowed me to perform a preliminary life cycle assessment on microbial electrochemical cell (MXC) technology that SCEB is researching as part of a Strategic Environmental Research and Development Program (SERDP) project. Currently, forward operating bases (FOBs) receive all of their potable and non-potable water in tanker truck convoys that utilize a lot of fuel for transportation and are targets for insurgents in hostile areas resulting in casualties. We propose that MXCs can be used to treat wastewater onsite to produce non-potable water for reuse, thereby reducing the amount of water that must be shipped to the FOBs. My analysis allowed me to compare the status quo treatment systems with different MXC configurations. My preliminary results demonstrate that the largest environmental impacts are from the transportation of water to the FOBs, not from the operation or manufacturing of the MXCs. (You can read more here.) Therefore, we are focusing on understanding how our MXC process can lead to increased wastewater reuse, decreasing the amount of water that would need to be transported to the FOB and, therefore, the environmental impact of these FOBs.