Lifecycle assessment (or analysis), better known as LCA, is a buzz term pertaining to sustainability that we’re hearing a lot more, but often don’t really understand.
So, what exactly is LCA? Generally speaking, LCA is a process used to examine, identify and evaluate the energy, material and environmental implications of a material, process, product or system across its lifespan from “cradle to grave.”
Let’s say we want to know whether it’s more sustainable to make ketchup from tomatoes organically grown in smaller farms distributed across the United States or from large-scale commercial farms primarily located in California. First, we need to define which specific criteria we will evaluate in order to determine sustainability. Measuring the greenhouse gas emissions produced from an activity is a typical metric used, and probably the most familiar one. However, other metrics—fuel usage, water consumption, release of hazardous chemicals, and even economic parameters (e.g., operating expenses, capital expenditures)—can also be included in the analysis. Once the criteria are defined, the LCA process then quantifies these metrics.
Historically, LCA evolved from the product manufacturing sector and has been used since the 1980s by academics and by research and development teams to address larger-scale environmental questions, including determining the level of greenhouse emissions being produced by major industry sectors and whether rising carbon dioxide levels are due to human interaction with our environment or part of a naturally occurring cycle.
Today, refinement of the LCA process has increased its utility, and vast improvements have been made in the data used to quantify various parameters (called inventory data). These factors have allowed LCA to be implemented on both small and large scales, as well as across many different industry sectors, making it an appropriate decision-making process for everyone from policymakers to industry personnel.
LCA’s greatest value is that it can answer industry questions that are perhaps less obvious because there are simply too many variables to account for. For example, LCA can be used to determine the point at which the distance that a truck must travel to transport organics to a composting facility becomes so great that the cost of fuel and truck wear-and-tear is higher than the economic/environmental benefit of composting, therefore making it more sensible to landfill the organics. And LCA can tell us the costs of reducing the environmental impacts associated with waste management systems, helping us determine whether we should recycle paper or burn it for energy. As better data becomes available, the variety of questions that can be answered through LCA becomes more detailed and discrete, allowing LCA to be applied on a city-wide or company-wide basis.
As a tool, LCA typically consists of a software model that allows a user to create inputs to answer a specific question. Of course, LCA is limited by the amount of accurate inventory data available to quantify its parameters. Another key restriction on LCA’s use is that the models available are often cumbersome and not particularly applicable to the solid waste field. Recently, the Environmental Research and Education Foundation (EREF) funded LCA development research with the goals of providing a more user-friendly LCA interface and creating LCA tools that are specific to the solid waste management industry. The EREF-funded tool, now in its final stages of development, is called the solid waste optimization lifecycle framework, or SWOLF. As societal activities become more intertwined and solid waste management gets more complex, processes like LCA and tools like SWOLF will become more and more necessary for evaluating economic and environmental trade-offs, as well as demonstrating to policymakers and municipalities alike how sustainability targets can be met.
Bryan Staley, P.E., Ph.D., is president of the Environmental Research and Education Foundation, a nonprofit organization that funds and directs scientific research and educational initiatives to benefit industry participants and the communities they serve.