The environmental impacts of the recycling technology which is available for crystalline Si, thin-film Si and CIGS PV modules were evaluated. The recycling of these PV modules results in net environmental benefits according to Global warming potential (GWP); Acidification potential (AP); Human toxicity potential (HTP); and Abiotic resource depletion potential (ADP). On the other hands, although net impacts are small, it is resulted the environmental burdens on Photochemical ozone creation potential (POCP) and Eutrophication potential (EP) outweigh the avoided burdens by recycling efforts. However, technology improvement and efficient transportation will contribute to reducing these impacts.
Summary To evaluate whether replacing an existing product with a new, more energy‐efficient product is environmentally preferable, we used an assessment approach based on life cycle assessment. With this approach, consumers can assess various replacement products, including products of different sizes or environmental performance in addition to consideration of various conditions of product use. The approach utilizes a diagram in which replacement conditions of products are compared with iso‐environmental‐load lines to determine the appropriateness of replacement. The approach also allows the assessment of energy and resource consumption and environmental impacts not only during the use stage, but also at other product stages. Iso‐environmental‐load lines to assess delayed replacement were also examined and derived. We then applied the approach in a case study of energy consumption by replacing three types of electric home appliances in Japan: TVs, air conditioners, and refrigerators. The results of assessment showed that replacing refrigerators after 8–10 years of use was preferable even if the replacement product was larger. The appropriateness of replacing TVs and air conditioners based on energy consumption depended on the replacement product and on the duration of daily use, and in several cases, delayed replacement was preferable. Replacement of air conditioners after 8–10 years of use was not preferable if the consumer already owned the most energy‐efficient product at the time of the purchase. The necessity of accounting for a variety of available replacement products was confirmed.
Ministry of the Environment examined methods to quantitatively assess impacts on global water resources and water environment due to human activities, aiming to increase public awareness of water saving and water conservation by using a quantitative index. Though ISO standardization process has been proceeding, concrete quantification methods and usage of the quantified results have not been considered so much in Japan. To establish water footprint as an index that appropriately reflects the impacts on water environment, in line with the moves of such international standardization, we developed the technical guidelines to provide with domestic business. Based on the considerations described above, we considered a “Water footprint case studies on quantification methodology”, aiming that domestic business can use it as a reference manual in quantifying water footprint of its own products. In this review, I introduce a case study of water footprint on clothes and issue.
High speed multi serial-link devices are rapidly applied in the field of network server and switch. To achieve high pin count (exceeding 2,000 pin) and high speed devices, we have been developing FC-BGA (Flip-chip BGA) package applied high-density organic substrate to achieve multi Gbps transmission [1]. The demand of signal speed approaches 28Gbps, and multi-lane serial links are also required. There are some reports over 28Gbps transmission by electrical signal transmission [2]. On the other hand, the DC-block (AC-coupling) technique for serdes transmission method is commonly used in the field of high speed communication. This DC-block method can cancel the offset voltage of the direct-current between input and output circuit, set the optimize voltage of the receiver circuit, control the level shift and reduce the common noise. There are many advantages by adopting DC-block functions. On the other hand, there are some challenges regarding the design of mounting parts and signal integrity. In general, DC-block functions are achieved by mounting chip capacitors in series into serdes signal lines, and there are commonly mounted on PCB (printed circuit board) or connectors, moreover there are some approaches to improve the signal integrity by the PCB design or the connector structure [3]-[4]. However, if multiple DC-Block capacitors are arranged near the devices, the mounted area and PCB signal routing area are restricted and the power supply planes are weakened. In addition, multiple vias must be arranged to connect between DC-block capacitor and inner signal trace, because the PCB trace is generally preferred strip-line structure to reduce crosstalk noise. Furthermore, significant impedance discontinuity is occurred at both DC-block capacitor and vias. These problems will be more critical to achieve multi-28Gbps serial-link with DC-block capacitors on PCB. In order to solve these problems we have developed advanced FCBGA equipped DC-block capacitors on the package.
3D multi-chip stacking is a promising technology poised to help combat the "memory wall" and the "power wall" in future multi-core processors. However, as technology scales and the chip sizes increase due to the number of transistors, interconnects have become a major performance bottleneck and a major source of power consumption for microprocessors. In this article, we introduce a TSV-based ultra-wide inter-chip connection technology that enables systems to have lower power consumption, higher scalability in its functionality and performance just by increasing the number/type of chips, allows to be manufactured with much more flexibility, and has a better cost/performance than conventional 2D SoC based designs.
