We developed an analytical model for automobile technology assessment, named CEAMAT (Cost and Effectiveness Assessment Model for Automobile Technologies). In this paper, the model was demonstrated in the application of costeffectiveness analysis of the future automobile technologies. Two technology scenarios, frozen and progress, were analyzed using CEAMAT, and the technological progress was evaluated to have substantial impact on CO₂ reduction, -27% compared with technology frozen scenario. However, the average reduction cost was estimated to be -11 to 24 thousands yen/ton-CO₂, which is decreasing yearly from 2010 to 2050. In addition, even in the technology progress scenario, the next generation automobile technologies, like Plug-ins, EVs, or FCVs, were found to remain too expensive to diffuse. If CO₂ should be reduced drastically in the middle to long term, these results imply that integrated approach including not only technological progress but also traffic flow improvement would be required.

View full abstract

This report summarizes recent international transfer of CO₂ emission embodied in trade in Japan, China, US and UK. In particular we focused on the period after the year 2000, when drastic changes in trade structure has taken place since BRICS countries have emerged. We estimated net imports of CO₂ emission embodied in traded goods after 1991 based on aggregate data of each country, which have increased significantly after the year 2000. UK imported as much as 44%, Japan, 38%, US, 20%, respectively, of the domestic emission at 2005: meanwhile, 27% of domestic emission in China in 2004 was induced by its export. We estimated CO₂ emission embodied in trade of steel industry after 1990 as a typical energy-intensive industry. In Japan and China, CO₂ emission was driven by domestic production for exports. UK and the US, in contrast, increased much CO₂ emission abroad by their imports. Then, we also estimated CO₂ emission embodied in trade of textile industry after 1990 as a typical energy-non-intensive industry. The developed countries, Japan, the US and UK, induced more CO₂ emission abroad than that emitted at home. Accordingly, in 2004, China exports 33% of domestic CO₂ emission in textile industry.

View full abstract

NO_x emitted from diesel is one of the main air pollutants for most countries. To reduce the emission of NO_x could promote to diffuse diesel vehicles. A NO_x storage / reduction (NSR) catalyst has been developed for the diesels. The catalyst in NSR is strongly poisoned by sulfur. We have researched reaction characteristics of CaCO₃ with sulfur dioxide by using a thermogravimetry. We obtained desulfurization breakthrough characteristic for CaCO₃. As a result, packed bed reactor of CaCO₃ absorbed SO₂ about 0.174 g-SO₂/g- CaCO₃. The absorption efficiency of CaCO₃ was more than 99.4%. According to this result, it was found that the necessary amount of the absorbent was supposed to be 1.40 kg or 1.68 L for 100,000 km running.

View full abstract

We propose a new closed cycle oxy-fuel gas turbine power plant that utilizes a nuclear heat generator. A pressurized water reactor (PWR) is designed to supply saturated steam to an oxy-fuel gas turbine for a specific power output increase. The saturated steam from the reactor can have lower pressure and temperature than those of an existing PWR. In this study, we estimated plant performances from a heat balance model based on a conceptual design of a hybrid plant for different inlet pressures of the gas turbine. The generating efficiency of an oxy-fuel gas turbine plant without a nuclear steam generator is estimated to be less than 35%. In contrast, the proposed plant has more than 40% of the whole generating efficiency. In the proposed plant, the power output contributed by a PWR is obtained by subtracting the LNG contribution from the whole power output. Supposing the generating efficiency of the LNG system in the proposed plant equals to that of the conventional plant, the efficiency of PWR system contributing to increase the generating performances of the proposed plant is estimated to be around 45%, even if the steam conditions are lower than in an existing PWR.

View full abstract

We focus on Japanese electricity exchange market. Currently, the 9 electric power companies in Japan carry the dominant influence as a seller side in JEPX transaction substantially. Therefore the aggregated marginal generation costs of the 9 electric power companies become major factors in the spot pricing mechanism in JEPX. Based on these facts, the fluctuation mechanism of electricity spot prices in JEPX depends on the supply side to a large extent. This paper addresses the challenge of building spot prices modeling for JEPX using a modified hybrid price model which can take not only cost-based issue but also market-based issue into consideration. The price model is decomposed into expected value part and indeterminate part. In order to represent the expected value part, we apply the Hill function, which can well fit the feature of 9 electric power companies’ aggregated marginal cost. We also apply the time series model to represent the indeterminate part. We forecast the spot prices using the model for verification of the model, and validate its good forecasting performance. Our model is suitable for the electricity exchange market in Japan.

View full abstract