Life cycle analysis (LCA) is a technique used to assess the environmental impact of a product or service from the moment it is extracted from raw materials, through its production and use, to its final disposal.
A complete LCA analysis provides a cradle-to-grave assessment of the whole value chain and has a well-defined description of its boundaries to the Earth system. LCA analyses can be performed via a series of commercial tools, but these are not a necessary criterion to perform a study according to the ISO standards 14040, 14044, and 14025 describing requirements and guidelines for executing such studies.
The LCA process typically involves four main steps:
In the goal and scope definition step where the objectives and boundaries of the study are determined (i.e., its frame to the outside world).
In the inventory analysis step, data is collected on the inputs and outputs of the product or system being studied. This includes a quantification of raw material extraction, energy use, and waste generation.
The impact assessment step, the environmental impacts of the product or system are calculated based on the inventory data. This includes assessing the potential impacts on air and water quality, biodiversity, and climate change.
The interpretation step, the results of the LCA are presented and discussed, and recommendations for improvements are made.
LCA analyses help decision makers to identify and quantify the environmental consequences facing decision gates, and it may provide a qualified approach to reduce the environmental footprint of products and services. The methods enable us to quantify the impacts of e.g., circularity in the material streams, if products can be re-used or re-purposed into second life usage, if a product can be repaired when broken, or dismantled so the raw material can be recycled into new products.
The world is a finite physical system and with a growing population, it is becoming increasingly important to consider ‘resource flow’ and ‘resource efficiency’ during planning. These concepts are used to determine how effective a physical input factor is being used to meet a desired outcome. In a world less plentiful these analyses are becoming increasingly important – see an example of how this is included in the policy developments at EU level, and how integrated product policies are developed in a common market (REF 1). In consequence, LCA-analyses are becoming increasingly useful in economic analyses, and further in financial climate risk assessments because the material input factors such as energy, material, emission costs are becoming more correctly priced. Mark however, the link between the physical quantities (energy, water, raw material, etc.) and the financial quantities (not conserved) is only valid if prices are adequate1.
When assessing the realism and usefulness of an LCA analysis framing needs special attention. What are input and outputs? How are these connected to the outside world, i.e., the elements not included in the analysis? Several authors claim that a full analysis encompasses the whole Earth system, while others claim it is more useful to narrow down the analysis to single industrial operations.
When comparing all physical factors (energy, material and water consumption, spillage, emissions, waste, and pollutants) in alternative industrial processes LCA can help identify the most sustainable way forward. Such analyses can be done in the design phase, and/or after an industrial application has been established while looking for incremental improvements. LCA provides a comprehensive view of the environmental impact of a product or service, rather than focusing on just one aspect.