Life‑Cycle Assessment (LCA) is a systematic method to evaluate a product’s, process’s, or service’s environmental impacts throughout its entire life cycle—from raw material extraction to end‑of‑life. This holistic and integrated approach considers every stage of a product’s life cycle and identifies key environmental factors and associated impacts.
An LCA typically consists of four main steps. Each step is essential for conducting a complete and reliable LCA :
1. Definition of goal and scope :
In this first step, it is crucial to clearly define the LCA’s goal—what you aim to assess or compare. For instance, comparing two similar products to determine which has the lower environmental impact. The scope sets the system boundaries by specifying which life-cycle stages are included (from raw materials to end-of-life) and which environmental impacts will be assessed (e.g., greenhouse gas emissions, water consumption, resource depletion, etc.).
2. Life‑cycle inventory
This step involves collecting and quantifying all inputs and outputs at each life-cycle stage. This includes the consumption of raw materials, energy, and water; emissions to air; generated waste; etc. Data can be sourced from specialized databases, scientific studies, industrial data, or specific surveys.
3. Impact assessment
Once the inventory is complete, the data is used to evaluate potential environmental impacts at each stage. Standardized impact assessment methods convert inventory data into understandable environmental indicators such as CO₂ equivalent emissions or resource depletion in oil-equivalent.
4. Interpretation of results
In this final step, LCA results are interpreted to support informed decision-making. This includes comparing options, identifying life-cycle hotspots where improvements can be made, evaluating mitigation measures, and communicating results to stakeholders to raise awareness of environmental impacts.
Key considerations for meaningful LCAs
1. Data consistency and accuracy
– Use up-to-date, reliable, and representative data. Uncertainties must be evaluated and reported transparently.
– Example: Without knowing the transport method (sea, rail, air) for a 1 kg item from Shanghai to Antwerp, CO₂ emissions estimates can be significantly off.
At Loopipak, we use LCA to compare the use of single-use plastic or cardboard with reusable envelopes or returnable shipping cases.
2. Normalization and impact categorization
– To allow comparison, LCA results are often normalized into common environmental categories (climate change, resource depletion, water pollution, etc.), enabling consistent quantification and comparison.
3. Selection of relevant indicators
– Choose indicators aligned with your environmental goals, e.g., CO₂ equivalent for climate impact, but also others to avoid burden shifting between impact categories.
4. Comprehensive life-cycle coverage
– An LCA must include all stages—from raw material extraction to end-of-life (production, transport, use, disposal, recycling). Omitting stages may lead to under- or over-estimation of impacts.
Limitations and challenges of LCA
1. Simplifications and assumptions
– LCAs often rely on averages or defaults when specific data is unavailable, which can introduce inaccuracies.
2. Data uncertainty
– Origins include measurement errors, assumptions, and temporal variations. Transparency is essential to avoid misleading conclusions.
3. System boundary constraints
– Excluding important life-cycle stages or interactions can bias results. LCAs typically don’t incorporate social or economic aspects.
4. Data availability challenges
– Detailed life-cycle data is hard to obtain, especially for complex products or companies lacking data collection systems, making LCAs time-consuming and costly.
Takeaways
LCA is a powerful method to evaluate environmental impacts over the life cycle of products, processes, or services. By clearly defining objective and scope, compiling inventories, assessing impacts, and interpreting results, LCA supports informed decision-making and comparison of options. However, limitations and uncertainties must be acknowledged to avoid biased conclusions.
List of key LCA standards
ISO 14040:
Establishes principles, framework, terminology, and key stages (goal, inventory, impact, interpretation), with guidance on reporting.
ISO 14044:
Builds on ISO 14040, providing detailed recommendations for data collection, impact evaluation, uncertainty analysis, etc.
ISO 14025:
Defines guidelines for Type III Environmental Product Declarations (EPDs) based on LCA results.
Why these standards matter:
1. Ensure consistency and comparability across LCAs.
By following common methodologies and principles, results become more interpretable and comparable across studies and industries—supporting informed decisions based on robust environmental data.
2. Promote transparency and credibility.
Standards also promote transparency by mandating full disclosure of methodologies, data, and assumptions, which strengthens credibility and allows stakeholders to evaluate reliability.
3. Best‑practice guidance
Moreover, they offer best‑practice guidance to avoid common errors, identify uncertainties, and improve overall quality—essential for scientific rigour and valid results.
4. Communication of LCA findings
Finally, standards guide the communication of LCA findings—critical for informing consumers, stakeholders, and decision‑makers. Clear, transparent environmental declarations help effectively share performance data.
Conclusion on Standards
International standards such as ISO 14040, ISO 14044, and ISO 14025 define best practices for conducting LCAs, ensuring consistency, transparency, and credibility. They offer detailed guidance on LCA execution, impact assessment, reporting, and results communication. By adhering to these standards, practitioners can produce reliable, comparable outcomes that enable informed environmental decision‑making.
Life‑Cycle Assessment (LCA) Explained in Detail