LIFE CYCLE ASSESSMENT (LCA)
What is LCA?
Life cycle assessment (LCA) is a method for measuring the environmental impact of a product throughout all stages of its life cycle, including its resource efficiency and waste generation capacity. Life cycle assessment (LCA) involves the evaluation of some aspects – often the environmental aspects – of a product system through all stages of its life cycle. Sometimes also called “life cycle analysis”, “life cycle approach”, “cradle to grave analysis” or “Ecobalance”, it represents a rapidly emerging family of tools and techniques designed to help in environmental management and, longer term, in sustainable development.The LCA studies we conduct are in accordance with ISO 14040/44 standards, and they cover the total amount of greenhouse gas emissions generated during raw material extraction, processing, production, end of life, and disposal stages.
A growing need
Sustainable development is now on the national and international agendas. It requires many things, but above all it requires rapid improvements in eco-efficiency, or in the efficiency with which we use energy and a wide range of materials taken from nature, and how we minimise waste. This builds on the long-running international interest in socalled “cleaner technology”. Even more demanding, however, sustainable development calls for eco-efficient improvements throughout the life cycle of a given product or system.
What is a product’s life cycle?
Simply stated, the life cycle of a product embraces all of the activities that go into making, transporting, using and disposing of that product. The typical life cycle consists of a series of stages running from extraction of raw materials, through design and formulation, processing, manufacturing, packaging, distribution, use, re-use, recycling and, ultimately, waste disposal.
The producer’s responsibility
Once, a manufacturer simply handed a product over to a distributor or customer, and that was the end of the story. No longer. These days it is widely recognised that any producer works with “chains” of suppliers “upstream”, and chains of customers “downstream”. The producer’s responsibility no longer ends – if it ever did – at the factory gate. Increasingly, industry accepts that product stewardship is the way forward. Governments, too, are beginning to impose “take back” requirements, to make producers take their wastes back and reprocess at least a proportion.
What are the benefits of doing an LCA?
The results of an LCA can help businesses, policymakers, and other organizations make more informed decisions to advance towards sustainability. It provides critical data that can support the following:
- process and product-design improvement
- marketing (e.g., backing up environmental claims or meeting consumer demand for green products)
- hot-spot analysis to facilitate continuous improvement
- third-party verification or certification
- method for quantifying key environmental impacts (e.g., greenhouse gas, carbon emissions, water use, and energy consumption)
- goal-setting for climate-change and other sustainability policies
How is environmental impact measured?
Sustainability can seem like an abstract idea. An LCA helps to make it concrete and actionable through the scientific measurement of environmental impacts.
Industrial activity interacts with the environment in many ways. Some of these are immediate, while others may occur far from the company’s actual location, thanks to the reach of global supply chains. Industry, in all its varieties, draws upon many activities and processes—diverse resources are consumed along the way as different substances are emitted. An LCA helps to determine to what extent these material exchanges with the environment are detrimental to both natural ecosystems and human health.
When an LCA is performed, a practitioner will set metrics to quantify the different inputs (e.g., energy, water, resources, land) and outputs (e.g., emissions, wastes, products) that occur throughout the life cycle of an industrial process, technology, or commodity. It allows an assessor to map flows of energy, resources, and materials in and out of a system. These are objective measurements, tracking distinct quantities like volume, mass, or weight. They are collected as part of the life cycle inventory (LCI).
The LCI data is interpreted later in the study, during the life cycle inventory assessment (LCIA), to represent actual impacts on the environment or human health. For example, a certain volume of petroleum may be used to produce one plastic fork. This is recorded in the LCI. In the LCIA, this measurement is used to calculate how much this contributes to global warming.
Environmental impact categories
Every LCA sets out specific environmental impact categories that guide the direction of the LCIA. There are many different LCA methods and each utilizes a unique set of categories. However, there are general types found across all methods, though different wording and metrics may be used.
- climate change (contribution to global warming)
- acidification (contribution to the occurrence of acid rain)
- energy (cumulative energy demand and loss throughout a life cycle)
- eutrophication (the release of nitrogen and phosphorous, which leads to algal blooms)
- radiation
- land use
- air pollution
- resource depletion
- water use
- ecotoxicity (the release of toxins that are harmful to life)
What are the 4 stages of an LCA?
Generally LCA has four stages or components:
1. Goal and scope
2. Inventory
3. Impact assessment
4. Improvement assessment
1. Goal and scope of an LCA
What are we looking at? The point at which all decisions are made about what to include in the study, why it’s being carried out, the “functional unit” that is being focused on, the different systems that need to be investigated, as well as the boundaries – it’s often not practical (or possible) to measure every single input and output and in the cases where there is good reason to think they are small or where they are deemed to be beyond the scope of what you are interested in, they are left out. Every LCA has boundaries. This is also the point where you ask what data do you need, what are your data quality requirements, what methods will you use to assess impact, to interpret, and how you will report it.
Another task at this point involves “screening”, which is the preliminary execution of the LCA and any adjustment in the plan.
2. Inventory
Every LCA has an inventory. This is the data that you are collecting. The inventory includes things like emissions, energy requirements and material flows for each process involved. These are the flows into and out of the system you are studying. The data of these are adjusted depending on the functional unit you’re looking at.
This is known as a Life Cycle Inventory (LCI)
This can be extremely complex because it can involve dozens of separate processes, as well as hundreds of tracked substances. This is where most of the complexity of an LCA is involved.
3. Impact Assessment
The Life Cycle Impact Assessment (LCIA) is where the impacts on the environment are calculated. The categories of impacts are chosen and the impacts on them based on the flow of emissions, energy and material from the inventory, are assessed.
There are lots of different types of impacts (depletion of abiotic resources, global warming, ozone layer depletion, acidification, etc) so this stage accounts for all the different impacts that have been chosen.
4. Improvement Assessment
Finally, the results are analysed in the context of the goal and scope of the study set out at the beginning. What have we learned about the system from this LCA? This is where recommendations are typically included.