Appendix - Ecoprofile methodology

Recent years have seen an increasing interest in describing the performance of extended industrial systems in terms of the consumption of energy and raw materials and the emission of solid, liquid and gaseous wastes. In this context, an extended system is one that starts with raw materials in the earth and traces all industrial and consumer operations until final disposal of the product at the end of its useful life and is often referred to as a cradle-to-grave analysis or a life-cycle inventory (LCI). Such descriptions inevitably require data for a wide range of different industries and this information is frequently obtained from published work, often of uncertain validity. As a consequence, many industries have initiated projects to examine their practices and provide this information for wider dissemination so that the use of unreliable data cannot be justified.

A2. Overview of ecoprofile methodology

Manufacturing industry is concerned with processing materials and the operations involved in this processing are governed by the laws of science. Two consequences follow from this. First, energy is needed to effect the desired transformations and secondly, waste is inevitably produced. The notion that it is possible to produce an energy-free and waste-free industrial process is a myth. As a result, the best that can be achieved is to minimize the use of energy and reduce waste production. The first step in attempting to achieve this is to describe the situation that currently exists, because this is the basis against which any future improvements will be judged.

Within individual factories, this has been a task of engineers for well over a century because energy use and waste generation directly affect the profitability of an enterprise. However, the last twenty years have seen the development of a further stimulus in the form of environmental pressures from both governments and public opinion.

When this type of work first started, interest focused initially on the use of energy, especially fossil fuels, and the work was often referred to as energy analysis. Because the calculations required the construction of balanced flow charts to describe the process, the consumption of raw materials and the generation of solid waste were also automatically calculated. As a result, some analysts referred to the work as resource analysis or resource and environmental profile analysis.

One of the earliest reports of the results of this type of work was presented to the World Energy Conference in 1969 ⁵ and concerned some aspects of the chemical industry. This was followed in the early 1970's by the publication of a large number of reports on various production systems, especially packaging systems, and the work was given added impetus by the oil crises of the mid 1970's. As a result many companies elected to have their practices examined and reports and publications have continued to appear right up to the present day although many of these reports have remained confidential to the sponsoring organization and are not freely available.

It is, however, important to remember that long before the interest in energy occurred, there was an awareness in many parts of the world of the localized pollution problems being caused by other human activities. Litter, the smogs of Los Angeles and Tokyo and acid rain in Scandinavia all pointed to the need for international action to curb the problems. Then in the 1980's the potential threat of global warming and ozone depletion added to the need to consider the emission of pollutants both to air and water. The methodology for evaluating the global release of these pollutants is identical to that for calculating energy consumption and so energy analysis expanded to encompass their computation. As a result, the term energy analysis fell into disuse and the terms eco-balance, eco-profile, cradle-to-grave analysis, life-cycle analysis and life-cycle assessment appeared, all essentially describing the same type of work. In the present work, the term eco-profile has been used rather than life-cycle analysis because the systems examined follow the production sequence only to the point where the product is ready for sale to the converter; the use and final disposal are not considered and so the results do not represent a complete life-cycle analysis. Such analyses are often referred to as cradle-to-gate analyses.

A3. Impacts and inventories

In 1990, the first ever meeting of some of the practitioners in this field of study met at a conference in Vermont. ⁶ Perhaps the most important conclusion of this workshop was a recognition that although the inputs and outputs to any industrial system can be measured or estimated, the causal link between many of these parameters and observable environmental impacts was simply unknown.

It was thought helpful therefore to separate this type of work into three distinct phases as shown in Figure 1.

Figure 1.
The three main phases of a life-cycle assessment.

1. The inventory phase - where the aim is to provide a detailed description of the inputs of raw materials and fuels into a system and the outputs of solid, liquid and gaseous wastes from the system.
2. The interpretation phase - where the inventory results are linked to identifiable environmental problems.
3. The improvement phase - in which the system is modified in an attempt to reduce the environmental impacts. Once the improvements have been suggested or implemented, the inventory is performed again to see if the expected changes have occurred but also to identify if any unwanted side effects have accidentally been introduced.

Of these three phases of a LCA, the methodology for the inventory phase is well established, based on the detailed work of the previous twenty years. In contrast, the interpretation phase is less well developed. The nostrum that less-is-better, which had been widely used in energy analysis can readily be applied to energy and resource use.

However, while its application to air, water and solid waste emissions seems attractive, there is only a remote possibility of being able to reduce all of these characteristics simultaneously, because they are usually interlinked. Without some guidance about the relative global importance of the different emissions, suggested courses of action to improve the current state could well make matters worse.

Since 1990, this simple three-stage view of an LCA has been modified in a variety of ways by different researchers and the individual stages have been repeatedly sub-divided (See, for example, the recent ISO Draft Standard ⁷). Never-the-less, it is useful to retain the three stage concept because it highlights the essential differences between the different phases of an LCA. The present report is essentially an inventory which forms part of an LCA and considered neither interpretation nor improvement.

⁵ H Smith. Transactions of the World Energy Conference, 18, Section E. (1969).

⁶ Society of Environmental Toxicology and Chemistry (SETAC). A Technical Framework for Life-Cycle Assessments. Washington DC, (1991)

⁷ International Standards Organisation 1996. Draft International Standard ISO/DIS 14040: Environmental Management - Life Cycle Assessment - Principles and Framework.