Yuichi Moriguchi

Methodology and Indicators of Economy-wide Material Flow Accounting

Summary This contribution presents the state of the art of economywide material flow accounting. Starting from a brief recollection of the intellectual and policy history of this approach, we outline system definition, key methodological assumptions, and derived indicators. The next section makes an effort to establish data reliability and uncertainty for a number of existing multinational (European and global) material flow accounting (MFA) data compilations and discusses sources of inconsistencies and variations for some indicators and trends. The results show that the methodology has reached a certain maturity: Coefficients of variation between databases lie in the range of 10% to 20%, and correlations between databases across countries amount to an average R 2 of 0.95. After discussing some of the research frontiers for further methodological development, we conclude that the material flow accounting framework and the data generated have reached a maturity that warrants material flow indicators to complement traditional economic and demographic information in providing a sound basis for discussing national and international policies for sustainable resource use.

CO2 Emissions in Japan: Influences of imports and exports

The amounts of CO2 embodied in imports to, and exports from, Japan have been estimated using input-output tables, assuming imported commodities have the same CO2 emission intensities as those of the corresponding Japanese products. The concept of the attributed CO2 emission to each country was introduced. Until 1985 in Japan, the amount of CO2 embodied in exports had been larger than that in its imports, but, by 1990, such a situation had been reversed.

Proposal of six indicators of material cycles for describing society's metabolism: from the viewpoint of material flow analysis

The first essential step toward promoting material cycling (recycling) is to understand the current state of the material cycles in a society. However, the types of material cycles that we should document and the methods of their quantification are not standardized. In addition, an important factor in promoting material cycling is the establishment of the indicators that will enable objective measurement of the effectiveness of policies and actions. This paper categorizes the forms of material cycles that we should document, discusses their characteristics, and proposes six indicators of material cycles for describing societys metabolism. We reached the following conclusions: (1) the forms of material cycles fall into three types, according to differences in how they are quantitatively measured and how they contribute to the objectives of material cycling: reuse of used products, recovery of by-products (as material and heat), and recovery of used products (as material and heat). They should be considered separately in terms of measuring material cycles and in establishing indicators of material cycles; (2) six indicators for measuring the material cycles are proposed, on the basis of the types and objectives of material cycling: direct material input (DMI), use rate of recovered used products (URRUP), material use efficiency (MUE), material use time (MUT), recovery rate of used product (RRUP), and domestic processed output (DPO). They reflect the main points in life cycles of materials; (3) three practical problems in capturing material flows and calculating the indicators exist: to capture by-products and used products that are not captured in current statistics, to distinguish between by-products and used products, and to capture product stocks.

Modeling of global biomass policies

Abstract This paper discusses the BEAP model and its use for the analysis of biomass policies for CO 2 emission reduction. The model considers competing land use, trade and leakage effects, and competing emission reduction strategies. Two policy scenarios are presented. In case of a 2040 time horizon the results suggest that a combination of afforestation and limited use of biomass for energy and materials constitutes the most attractive set of strategies. In case of a ‘continued Kyoto’ scenario including afforestation permit trade, the results suggest 5.1 Gt emission reduction based on land use change in 2020, two thirds of the total emission reduction by then. In case of global emission reduction, land use, land use change and forestry (LULUCF) accounts for one quarter of the emission reduction. However these results depend on the modeling time horizon. In case of a broader time horizon, maximized biomass production is more attractive than LULUCF. This result can be interpreted as a warning against a market based trading scheme for LULUCF credits. The model results suggest that the bioenergy market is dominated by transportation fuels and heating, and to a lesser extent feedstocks. Bioelectricity does not gain a significant market share in case competing CO 2 -free electricity options such as CO 2 capture and sequestration and nuclear are considered. To some extent trade in agricultural food products such as beef and cereals will be affected by CO 2 policies.

Size distribution and characterization of ultrafine particles in roadside atmosphere

Abstract The number concentration and number size distributions of ultrafine particles were measured with a Scanning Mobility Particle Sizer (SMPS) at a roadside in early autumn and winter, and the results are discussed with regard to the contribution of traffic activity and meteorological conditions. The number concentration of the <50 nm fraction increased in the morning under calm wind conditions, and this increase corresponded with the increase in total traffic volume and nitric oxide. The increase in ultrafine particles was influenced not only by the increase in total traffic but also by the high contribution of diesel engine vehicles. The number concentration decreased around noon as the wind speed increased, although the total traffic and the number of diesel engine vehicles were at the same level as in the morning. The number size distribution in the morning was bimodal, with a first peak diameter of around 30 nm and a second of around 90 nm in both periods. The volatility of ultrafine particles was investigated using a thermal denuder operating at 250°C. The first peak consisted mainly of volatile components, whereas the second one consisted of solid materials plus some volatile components. These results were consistent with the mass size distribution of elemental and organic carbon. The number size distribution with a peak diameter of around 30 nm was also observed in the afternoon at a suburban site; however, it was produced not by vehicle emissions directly but by photochemical reactions. Although a relatively high number concentration was also observed in the morning at the suburban site due to vehicle emission, the peak diameter ranged from 40 to 90 nm, which was larger than at the roadside.

Wood products: potential carbon sequestration and impact on net carbon emissions of industrialized countries

Abstract Carbon stocks in the wood products pool are considered to be increasing globally. Simplified methods for estimating the fate of carbon in wood products need to be prepared to allow estimation at the national level. Since current methods cause some problems when dealing with specific countries, we try to improve the current methods. We discuss the potential carbon sequestration in wood products and the impacts of three accounting approaches (IPCC default, stock-change and atmospheric-flow) on net carbon emissions of 16 industrialized countries. We draw the following conclusions: (1) we improved the current methods for estimating the fate of carbon by considering the recycling of paper and the use of other fiber pulp, but further improvement need to be made; (2) the annual carbon sequestrations in wood products during 1990–1999 correspond to a few to 10% of 1990 base-year emissions from fossil fuels and cement production, depending on country and year. For the analyzed countries as a whole, the annual carbon sequestration was around 2%; (3) the impact of the accounting approaches on net carbon emissions at the national level is significant. Therefore, policy implications must be carefully considered when one of these approaches is adopted.

Toward a Low Carbon–Dematerialization Society

Rapid industrialization and urbanization has been occurring in China since the introduction of the opening‐up policy in 1978. The demands of building and infrastructure construction have increased rapidly, especially in the transportation and housing sectors in China. Large amounts of construction materials have been required in building construction and maintenance of the railway and road systems, especially steel and cement. Continued cement and steel production will require heavy raw material resource consumption and will emit a great deal of carbon dioxide (CO). This study forecasts future steel and cement demand and related resource consumption and CO emissions for building and transportation infrastructure based on a material flow analysis of China. Furthermore, the effect of prolonging the lifetime of building and transportation infrastructure is appraised. The results indicate that building and transportation infrastructure will increase sharply through 2030. Although the demand for new construction will then decrease, steel and cement consumption will remain at a high level through 2050 because these are needed to maintain roads and railways. In addition, prolonging the lifetime of buildings and infrastructure is a useful way to avoid more raw material consumption and to mitigate CO emissions. However, its main effect is to decrease the demolition of buildings and reduce material use for the maintenance of roads and railways. Currently not enough countermeasures have been implemented to realize a low carbon–dematerialization society in the building and transportation construction sector. Future comprehensive efforts should include the reuse of waste construction material and a reduction in raw material consumption intensity by applying technical innovations.

Life-cycle analysis of charging infrastructure for electric vehicles

Life-cycle analysis of a charging station for electric vehicles (EVs) was performed in the three phases, that is, production, transportation and installation of the charging equipment, which consists of charger, battery and stand. We chose parking lots on expressways, commercial parking lots in cities, municipal facilities, shopping centers, etc. throughout the country as the charging sites according to the EV charge program in Southern California. Air-pollutant emissions during the transportation phase were calculated based on the emission factors of vehicles, running speed and the transport distance between one factory of the charging equipment and each site. The share of transporting the charging machines in total emissions of CO2, SOx and CO was less than 15% and the production phase was dominant. In case of NOx, the share of transporting them was over 20%. The relation between gasoline vehicle and gas station was applied to estimate the number of EVs using the charging stations through the country, and the contribution of the charging stations to life-cycle emissions of air pollutants from EV was presented. The share of infrastructure in total emissions of CO2 was 16% in our model case. Thus the development of the charging infrastructure almost did not change the advantage of EV compared to gasoline vehicle (GV) in terms of CO2, NOx, and CO emissions. But an EV emits more life-cycle SOx than gasoline vehicles (GVs).

Biomass strategies for climate policies

This paper discusses the results of the BEAP linear programming model that has been developed to study the optimal use of biomass and land for greenhouse gas emission reduction, notably the competition between food production, biomass production for energy and materials and afforestation. The model results suggest up to 100 EJ biomass use in case of global policies (about 20% of global primary energy use). The biomass is used for industrial and residential heating, transportation fuels and as a feedstock for plastics. In the electricity markets competing emission reduction options are more cost-effective than biomass. In case the Kyoto protocol is continued beyond 2010 the developed countries can rely in 2020-2030 on afforestation and land use change credits from developing countries, without any major use of other emission reduction strategies. However, in case of a planning perspective of more than half a century bioenergy is preferred instead of afforestation. The results indicate a limited impact on global agricultural trade, but food demand may be affected by CO 2 policies.

Six indicators of material cycles for describing society’s metabolism: application to wood resources in Japan

Abstract We estimated the material flows of wood resources during the period 1960–1999. By applying our six proposed indicators, we discussed the state of material cycling of wood resources. Through this analysis, we examined the utility and feasibility of the indicators: direct material input (DMI), use rate of recovered used products (URRUP), material use efficiency (MUE), material use time (MUT), recovery rate of used products (RRUP), and domestic processed output (DPO) for measuring the consumption of natural resources, recovery of used products (input side), recovery of by-products, reuse of used products, recovery of used products (output side), and the environmental load, respectively. We draw the following conclusions: (1) during 1960–1999, MUE (recovery of by-products) has been consistently high and both URRUP and RRUP (recovery of used products) have increased. However, DMI (the consumption of natural resources) and DPO (the environmental load) have not decreased. The recoveries of by-products and of used products have restrained the consumption of natural resources and the environmental load. However, they have not been able to reduce them; (2) MUE (recovery of by-products) is already relatively high. Therefore, the main goals in promoting material cycling in the future will be increase in MUT (reuse of used products), URRUP, and RRUP (recovery of used products). This is especially needed for used wood products. For wood products, MUT (reuse of used products) should be regarded as an important indicator as well as URRUP and RRUP (recovery of used products), because most wood products are durable. On the other hand, for paper products, URRUP and RRUP (recovery of used products) are more important than MUT (reuse of used products), because most paper products are used for short-term purposes; (3) the six indicators of material cycles are useful for analyzing the state of material cycles and discussing the future goals of material cycling. Among the practical problems in capturing material flows and calculating indicators, to capture the product stocks is most difficult to be solved.