Objective. The objective of the paper is to review the valuation method of environmental impact using the conjoint analysis. The conjoint analysis is one of the attribute-based econometric methods and estimates the monetary value of environmental attributes. This paper discusses the application of the conjoint analysis to the life cycle impact assessment.
Results and Discussion. In the literature of environmental economics, most papers used the choice experiment format, which asks respondents to choose their most preferred alternative from a set of alternatives. Current research of the choice experiment is focused on the econometric models for heterogeneity of preferences, including the random parameter logit, latent class logit, and hierarchical Bayes.
Conclusions. The validity of the conjoint analysis depends on the survey design and sampling design, because the method uses the stated preference data. Nation-wide, in-person interview is considered to be the best survey method for valuing environmental impacts on the whole country. The international comparison of the conjoint analysis for the life cycle impact assessment is important future research.
Ecological impact is usually evaluated by the value of ecosystem services. I introduce a method to evaluate biodiversity. The red data book of Japanese vascular plants is based on their extinction risk. During evaluation of this red data book, about 2000 taxa were evaluated using population data and rates of decline for ca.4400 grids, each of ca.100 km2. This database can be used to estimate the impact of human activity on extinction risk of threatened plants. In order to evaluate extinction risks and apply the evaluation to conservation actions, the mean time of extinction and discount mean time to extinction are defined as measures of extinction risk. The present value of a species’ persistence in the future decreases exponentially. Increases of the inverse, and logarithm, of the discount mean time to extinction are also considered measures of the extinction risk. We applied these measures to an environmental impact assessment for the Japanese World Exposition that was held in 2005, Aichi Prefecture. Development will have a greater impact on threatened Salvia species than star magnolia, which has been conserved by changing the site plan.
Increasing demand on freshwater due to population and economic growth in the world may cause severe effects on human and ecosystem. Particularly, available amount of freshwater resource is very limited but essential for living things. In this context, freshwater consumption related to products and systems has attracted considerable attention in LCA. The same amount of freshwater consumption will lead to different results in every area due to the abundance of water resource and socio/economic conditions. Therefore, methodologies for assessing the effects of freshwater consumption are necessary in LCA. State of the art methodologies for midpoint and endpoint assessment of freshwater consumption are introduced in this article. More progresses（like consideration of temporal factor and consumption rate, expansion of target endpoints）are expected for further improvement of reliability and preciseness of assessment results, but developed methodologies are applicable to specific assessment of products as feasibility studies. Feedbacks through feasibility studies will be useful to sophisticate methodologies and essential to fill the gaps between available and necessary information for inventory analysis and impact assessment.
Objective. According to the IPCC Fourth Assessment Report, it is predicted that the global warming promotes the outbreak of the waterborne disease (diarrhea). However, in the past LCIA studies on damage assessment of human health caused by global warming, heat stress and malaria have been mainly considered and there is little study taking diarrhea into account. Therefore the aim of this study is to quantify the health damage related to diarrhea caused by global warming based on statistical analysis. Materials and Methods. The procedure of this study is as follows: 1) Four SRES scenarios (A1B, A2, B1 and B2) were used to estimate the marginal temperature rise (2000-2100) by 1 kg-CO2 emission based on MAGICC (Model for the Assessment of Greenhouse-gas Induced Climate Change) model. 2) Increasing of diarrhea incidence caused by temperature rise was estimated based on the relationship between future temperature rise and future diarrhea incidence calculated by a multiple regression analysis. 3) Cases of diarrhea were calculated by multiplying population data and diarrhea incidence. 4) DALYs were calculated by multiplying the cases of diarrhea and the ratio of DALY and diarrhea case. Results and Discussion. Damage factors of diarrhea were calculated as 1.1-3.3×10−7 DALY/kg-CO2 for four SRES scenarios. The health damage of diarrhea around 2030 was the biggest in all regions and any scenarios. Africa and South East Asia regions showed bigger damage than other regions because their lower ratios of accessing to improved drinking water and large numbers of people. By a comparison of scenarios, A2 scenario showed the biggest damage, because the highest temperature rise and the lowest ratio of accessing to improved drinking water. Moreover, the result indicated that it is important to take diarrhea into account, because the damage of diarrhea caused by global warming is higher than other diseases. Conclusions. An approach of chronological order was used to quantify the health damage of diarrhea caused by global warming for each region and each scenario. Damage factors of diarrhea for four SRES scenarios were gained in the study.
Objective. Titanium dioxide photocatalysts is well known unique material which have the environmental improvement effect of removing air pollutant, NOx, since the discovery of Honda-Fujishima effect. TOTO Ltd. introduces the photocatalysts fixed coating, HYDROTECT, as the environmental technology. The aim of this research is to understand the environmental property of photocatalysts coating, compared with an ordinary coating. We investigated the environmental impact of coating by LCA.
Results and Discussion. Two results were obtained in the LCA evaluation of LIME2 method. At first, air purification is effective for human health hazard decrease in use phase, caused mainly by photocatalystic NOx removal effect with no external energy. Secondly, the long durable coating is effective for the resource use reduction.
Conclusions. Photocatalysts coating have the advantage on further environmental improvement compared with an ordinary coating. The current work showed photocatalysts coating have the distinguished environmental properties and make further environmental benefit for an ordinary coating.
Objective. Find out how containers impact the environment in order to advance containers designs that are friendly to the environment. Approaches for reducing the environmental impact of aluminum cans, PET bottles, and stand-up pouches, using the life cycle impact assessment have been studied.
Results and Discussion. Using the life cycle impact assessment method based on endpoint modeling（LIME2）to evaluate the environmental impact, the system boundary of this assessment includes from the material production phase to the product manufacturing, filling, use, disposal, and recycling phases. The results of the study indicate the following: 1）Aluminum cans have a large impact in terms of CO2 emissions, PM10 and waste. The effective way to diminish this impact is to reduce the quantities of aluminum plates used; however, it could be observed that the reduction of aluminum plate use resulted in increased SO2 emissions. For aluminum cans, we can suppose that a reduction of the volume of plates used should diminish the SO2 emissions as well, inventory data of the aluminum canstock manufacturing needs to be carefully investigated. 2）PET bottles have a large impact in terms of CO2 emissions and SO2 emissions. Reducing energy（electricity）consumption during the conversion process is the effective to reduce this impact. 3）Stand-up pouches have a large impact in terms of CO2 emissions and non-methane volatile organic compounds（NMVOC）. Reducing usage of plastic films and usage of organic solvent for the laminating and printing processes is the effective way to reduce this impact. However, a reduction of plastic films usage should be considered carefully as it reduces the energy recovery quantities and will affect, notably, coal usage.
Conclusions. We demonstrated that each type of container impacts the environment differently; the impact reduction approach will therefore be different. Furthermore, in order to complete the validity of this evaluation, it is necessary to take into account the different filling methods for each type of container.
Objective. Substations are built in a wide variety of places such as in mountains and cities. In many cases, these outdoor substations are built in mountain areas. A switchgear installed in an outdoor substation may be either a gas insulated switchgear（GIS）that uses SF6 gas as an insulating medium or an air insulated switchgear（AIS）that uses air as an insulating medium. Since the GIS insulates SF6 gas well, the GIS is smaller than the AIS. In this study, we compared environmental impacts of GIS and an old type AIS assuming they are used in a 145kV substation built in a mountain area based on LIME2 method.
Results and Discussion. Through the comparison, we quantified the environmental impact of the life cycle of each substation. When the integration result and the characterization result in terms of global warming were compared, the environmental impact of the substation using the GIS was 19% of that of the substation using the old-type AIS according to the consolidation result and 38% according to the characterization result.
Conclusions. This result suggests that when comparing facilities that use land in very different ways, it is desirable that the environmental impact on biodiversity and primary production be assessed in addition to global warming. It is desirable, therefore, that biodiversity and primary production data be prepared and improved.
Objectives. It is important to design a biofuels production and utilization system which can reduce economic cost and environmental load from the viewpoint of global warming prevention and energy safety. In this study, we estimated suitable numbers of bioethanol plants, construction sites of bioethanol plants, transportation routes of rice straw orienting cost minimization and greenhouse gas (GHG) emissions minimization which considered the characteristics of region such as distribution and quantity of rice straw, road network and distribution of biogasoline stations in Chiba prefecture. Also, we examined influence that abandoned cultivation lands use gave to the cost and GHG emissions of the bioethanol production utilization system. Furthermore, we performed sensitivity analysis about factors that influenced bioethanol production cost. Results and Discussion. We analyzed cost minimization, GHG emissions minimization, and total cost minimization for current condition scenario (scenario 1) and abandoned cultivation lands use scenario (scenario 2). The construction sites of bioethanol plants, transport routes of rice straw, the cost and GHG emissions were calculated in each scenario. The result shows that plants construction sites and rice straw transportation routes were different in the cost minimization and in GHG emissions minimization. The bioethanol production cost were estimated to be 133 JPY/L in the scenario 1 and 140 JPY/L in the scenario 2. The ratio of collection and transportation costs of the rice straw occupied about 30% of the total cost and was the biggest. The GHG emissions were estimated to be 1.31 kgCO2-eq/L in the scenario 1 and 1.41 kgCO2-eq/L in the scenario 2. The GHG emissions in bioethanol conversion process occupied about 70% of the total GHG emissions. GHG reduction effect was evaluated in the scenario 1 but was not evaluated in the scenario 2. The rice straw collection and transportation unit price influenced the bioethanol production cost most. Conclusions. The bioethanol production was unprofitable in each scenario. The finance supports from country/government and tax break are necessary for the bioethanol to be profitable. Since the rice straw collection/transportation cost accounts for a large part of the total cost in the bioethanol production system, it is significant to make the price competitive. The development of low cost technologies to collect rice straw and bioethanol conversion as well as a financial support system is needed. In comparison with the gasoline, the GHG emission reduction effect of the bioethanol was evaluated in the scenario 1. But the GHG emission reduction effect of the bioethanol was not shown in the scenario 2 because GHG emissions of cultivation stage are considered.