Life Cycle Analysis

Life cycle analysis or assessment (LCA) had its roots in the 1960's with the analysis of fossil fuel consumption. In the 1970's the Environment Protection Agency (EPA) refined the methodology and it was later adopted for waste analysis and finally as a business tool to determine the environmental impacts of products, processes or services, through production, usage, and disposal. LCA is now evolving as a valuable decision-support tool for both policy makers and industry to assess cradle-to-grave impacts of materials, products or processes.

Drivers for the development of LCA as a tool include:

  1. Government regulations for "life-cycle accountability;" whereby a manufacturer is responsible not only for direct production impacts, but also for impacts associated with product inputs, use, transport, and disposal.
  2. Participation by business in voluntary initiatives which contain LCA and product stewardship components. For example, ISO 14000 which seeks to foster continuous improvement through better environmental management systems.
  3. Environmental "preferability" in both consumer markets and government procurement guidelines.

Impact of TecEco Technology

The chemical composition of materials determines their net emissions whereas physical characteristics determine lifetime energies. Together the physical and chemical characteristics determine recyclability and environmental affects on disposal.

The TecEco technology will reduce the net emissions and embodied energy of materials used in construction. It will also impact on lifetime energies but this is very hard to calculate.

Spreadsheets for calculating the LCA of TecEco cements is available under the heading tools.

LCA Methodology

LCA takes a systems approach to evaluate the environmental consequences of a material, product or process. A complete LCA would have the following components.

  1. Goal definition and scoping: Identifying the LCA's purpose and the expected products of the study. Determining the boundaries (what is and is not included in the study) as well as assumptions based upon the goal definition;
  2. Life-cycle inventory: Quantifying the energy and raw material inputs and environmental releases associated with each stage of production;
  3. An evaluation of the potential environmental impacts associated with those inputs and outputs;
  4. An analysis of opportunities to mitigate the environmental impacts.

LCA's involve cradle-to-grave analyses of production systems and provide comprehensive evaluations of all upstream and downstream energy inputs and multimedia environmental emissions.

"Life-cycle" or "cradle-to-grave" impacts include the extraction of raw materials; the processing, manufacturing, and fabrication of a product; the transportation or distribution of the product to the consumer; the use of the product by the consumer; and the disposal or recovery of the material or product after its useful life.

 

Problems with LCA's

Limiting the use of LCA's as analysis techniques in both the public and private sectors is the need for more streamlined techniques and reliable methods for aggregating and comparing the numbers generated. Deciding which is the 'cradle' and which the 'grave' has been another point of contention. If LCA's are to have greater credibility there must be standardisation of methodologies, and consensus as to where to set the limits. Much of the focus worldwide to date has been on agreeing the methods and boundaries to be used when making such analyses and standardising methods of interpreting the collected data.

Preserving the confidentiality of commercially-sensitive raw data without reducing the credibility of LCA's is also a major problem. Not surprisingly. many of the studies which are published, and not simply used internally, endorse the views of their sponsors.

Recycling introduces a further real difficulty into the calculations. In the case of materials like steel and aluminium which can technically be recycled an indefinite number of times (with some melt losses), there is no longer a 'grave'. And in the case of paper, which can theoretically be reprocessed four or five times before fibres are too short to have viable strength, should calculations assume that it will be recycled four times, or not? What return rates, for example, should be assumed for factory-refillable containers?

For both refillable containers and materials sent for recycling, the transport distance in each specific case is a major influence in the environmental impacts associated with the process.

There are geographical problems as well as an LCA which concludes that recycling of low-value renewable materials in one city is environmentally preferable may not hold good for a different, more remote city where reprocessing facilities incur large transport impacts.

LCA's can tell us a lot about the embodied energy and emissions of a material, information about releases during manufacture and other impacts but they cannot tell us the effect on lifetime energy of using a particular material opposed to another. Materials that have significant embodied energy may have a much greater impact on reducing lifetime energy and so on. e.g. the glass in a window.

Why perform LCA's?

When first conceived, it was predicted that LCA would enable definitive judgments to be made. That misplaced belief has now been discredited. In combination with the trend towards more open disclosure of environmental information by companies, and the desire by consumers to be guided towards the least harmful purchases, LCA has become a vital reporting and analysis tool rather than a definitive judge.

All products have some impact on the environment. Some use more resources, cause more pollution or generate more waste than others. Breaking down the manufacturing process into fine detail as in an LCA can be useful in identifying improvements, showing where a more sustainable product could be substituted or more energy efficient process adopted.

Often LCA's are conducted to provide environmental data for the public or for government. In recent years, a number of major companies have cited LCA's in their marketing and advertising, to support claims that their products are 'environmentally friendly' or even 'environmentally superior' to those of their rivals. In most situations however it is impossible to prove conclusively using LCA's that any one product or any one process is better in general terms than any other, since many parameters cannot be simplified to the degree necessary to reach such a definitive conclusion and many of these claims have been successfully challenged by environmental groups.


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