Life Cycle Assessment

Life Cycle Assessment (LCA) is also known as Life Cycle Analysis or Ecobalance. It is defined in the ISO 14040 as the compilation and evaluation of the inputs, outputs and potential environmental impact of a product system throughout its life cycle. Thus, it is a methodology that analyses the environmental aspects and impacts at all stages in a product life cycle, from raw material extraction to production, use, end-of-life treatment and disposal i.e. cradle-to-grave.

There are a few parties that work for the LCA methodology and guidelines development. They are the Society of Environmental Toxicology and Chemistry (SETAC), Centre of Environmental Science, Leiden University (CML), the International Organisation for Standardisation (ISO) and the United Nations Environmental Programme (UNEP).

In SETAC's Code of Practice, it is recommended that the LCA be split into five stages:


1. Planning
  • Statement of objectives
  • Definition of the product and its alternatives
  • Choice of system boundaries
  • Choice of environmental parameters
  • Choice of aggregation and evaluation method
  • Strategy for data collection

2. Screening
  • Preliminary execution of the LCA
  • Adjustment of plan

3. Data collection and data treatment
  • Measurements, interviews, literature search, theoretical calculations, database search, qualified guessing
  • Computation of the inventory table

4. Evaluation
  • Classification of the inventory table into impact categories
  • Aggregation within the category (characterization)
  • Normalization
  • Weighting of different categories (valuation)

5. Improvement Assessment
  • Sensitivity analysis
  • Improvement priority and feasibility assessment

The main process in the LCA are the inventory table compilation that list down all resources consumed and all emission produced throughout the life cycle; and impact assessment process, where all the consumptions and productions impact to the environment are analysed and quantified.

The LCA provides very thorough analysis on the product and service. However, the process is time consuming and there are huge amount of data involved. Most of the LCA practitioners carried out the LCA on dedicated software. Among those softwares available in the market are GaBi and SimaPro, developed respectively by PE International and PRé Consultants.

The LCA would give quantitative results to evaluate the total environmental impact of a product. The assessment benefits the company in:-

  • Identifying opportunities to improve the environmental performance of products at various points in their life cycle (e.g. Analysing the origins of problems related to a particular product; Comparing improvement variants of a given product)
  • Informing decision-makers in industry, governmental or non-governmental organizations (e.g. strategic planning, priority setting, product or process design or redesign, comparable product selection)
  • Selection of relevant indicators of environmental performance, including measurement techniques
  • Marketing (e.g. an environmental claim, eco-labelling scheme or environmental product declaration)

Despite the amount of time and work it takes, LCA has some limitations such as:-

  • Not every aspect is quantifiable and LCA would need to involve some assumptions and value choices;
  • Choice of systems boundaries is critical for the evaluation and the rigid boundaries sometimes make it difficult to account the aspects and impacts;
  • The results accuracy is very much depending on the availability of the related data;
  • LCA only focus on the environment aspects of a product, while the social and economic aspects are neglected;
  • LCA is just an analytical tool to provide information that supports the decision. It cannot replace the decision making process itself.