Shinsuke Kondoh (Research Scientist), the Environmentally Conscious Design and Manufacturing Group (Leader: Nozomu Mishima), the Advanced Manufacturing Research Institute (Director: Hideto Mitome) of the National Institute of Advanced Industrial Science and Technology (AIST) (President: Hiroyuki Yoshikawa) and others have developed a total performance analysis and evaluation software that evaluates and analyzes the balance of values, environmental load and cost of products throughout the entire product life cycle.

Based on the assessment results of existing software, it was difficult to design and provide products of high value at low environmental load and cost throughout their entire life cycle (i.e. production, use and disposal) - which is indispensable for spreading environmentally conscious products. The newly developed software can contribute to the design, manufacture and spread of environmental-conscious products as it can evaluate changes in product value over time.

The software can be downloaded free of charge from October 16, 2008, from: http://unit.aist.go.jp/amri/group/ecodem/ja/TPA/ . The software will be exhibited as "Total Performance Evaluation and Analysis Tool of Product Life Cycle" at the AIST Open Lab held at AIST Tsukuba on October 20 and 21, 2008.

The spread of environmental-conscious products is needed to achieve a sustainable society.  However, factors such as safety, high performance and low-cost also are important.  To offer users high value at low-cost throughout the entire life cycle of products, in addition to a low environmental load, it is necessary to design products and a life cycle scenario - when and how do you reuse, recycle, maintain, upgrade and dispose them.  However, it was difficult for existing indices to evaluate product life cycles appropriately and to connect to an improvement in product design because value, environmental load, and the cost of products could not be evaluated at the same time.  In addition, the change of value of products over time could not be taken into consideration.  The development of a tool that can consider change in value over time is expect to clarify how profitable maintenance and upgrades are, and which parts of a product should be improved.

AIST has been researching design methods and manufacturing technologies for environmentally conscious products, such as the development of a micro-factory, which is a very efficient technique from the viewpoint of saving energy, resources and space, since before its reorganization into its current form. We introduced an indicator that evaluates the balance of the value of products, environmental load and cost in this research. Using the indicator, we then developed a design approach and software which improve the efficiency of products seen from both the environmental and the economic sides, based on the background that high value at low-cost is needed for products throughout production, use and disposal stages.

To help the spread of environmental-conscious products, this research offers a tool that guarantees users not only mere ecological images, but cost-effective products.  For companies, the tool enables development that takes into consideration the life cycle of products.  We expressed the overall environmental performance of products numerically and introduced the Total Performance Indicator (TPI) shown in Fig. 1.  Use value refers to convenience and satisfaction that users obtain by using products.  In the equation, use value is divided by the geometric mean of the environmental load and cost (price of products, electricity cost during their use and cost of disposing them) during the life cycle of products.  The larger this value, the greater the use value that has been achieved for the least environmental load and cost.

Figure 1. Total performance indicator

In general, the longer a product can be used while maintaining high value, the more users will tend to be satisfied with the product.  As for the "use value" of products, it is necessary to evaluate the total amount of value over the period from purchase to the disposal of products.  Products with a use value that is high and an environmental load and cost that are low, that is, a product with high total performance, are true environmental-conscious products.  How then, should use value be evaluated?  Figure 2 shows the relation between the change of value of a product over time and use value.  The vertical axis shows the value of a product at that time, and the horizontal axis shows elapsed time.  We assumed that product value decreased due to two factors: the performance of products physically deteriorated (they wore out or broke down, etc.); and two, the performance of products became "dated," (for instance, electronic devices such as personal computers are made obsolescent by putting new products on the market), and change over time has been calculated in this research.  In concrete terms, users' "Get tired" level to performance is evaluated by converting users' evaluation of the performance of products into price, and by evaluating this, for instance, at intervals of several years.  For personal computers, users valued the performance "speed of calculation," and the value that users cited in "speed of calculation for CPU of 1 GHz" was about 60,000 yen in 2002, and about 40,000 yen in 2006, determined by a questionnaire.  Thus, the change in value of "speed of calculation for CPU of 1 GHz" over time as seen by users is evaluated in this way.  Because the average usage years of personal computers are known from other investigations, it is understood when the usage period in Fig. 2 ends.  Then, the area under the change curve of value by time in the usage period can be calculated, and this becomes use value.  Therefore, the unit of use value in this research is price × time.

Figure 2. The concept of Use Value (UV)

Extending the usage period or a decrease in value slow-down, can increase the use value of products that correspond to the colored area in Fig. 2.  Plural functions (for instance, processing speed, memory capacity, and ease of viewing on the screen in the case of notebook computers) are included in a product, and each has a different rating.  Certain methods can raise the use value of products effectively, such as paying attention to functions with higher rating and with a lower environmental load and cost in improving performance, and making it possible to upgrade functions that become obsolescent quickly.  Moreover, it is effective in reducing cost and environmental load to reuse and recycle parts according to circumstances.

Figure 3. Screenshot of Total Performance Analyzer

We have developed a total performance analysis support software that makes it possible to present such a "design guide" to designers.  Figure 3 shows screenshots of a total performance analysis for a notebook computer.  The TPI improves by about 8% by reusing the case and LCD display, and by reusing or recycling the main board in trial calculations.  This corresponds to a reduction of about 15% in cost or environmental load alone.  It is possible that the development and spread of true environmental-conscious products that maintain high value at low-cost throughout their entire life cycle, in addition to being environmentally friendly, in these days when the purchase cycle of products such as personal computers and automobiles tends to be long.  It is thought that it is possible to contribute greatly to helping prevent global warming and to saving energy when we review a lot of products in this manner.

We are planning to disseminate our ideas on total performance evaluation and analysis techniques by opening the software to the public, and holding workshops, etc., and to execute case analyses for a variety of assembly products, so as to verify the effectiveness of this technique.  Moreover, we plan to collect the results of case analyses and make them available to the public, and to maintain a database through which users can easily execute total performance evaluation and analysis.