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However, practical use is not advanced as thought by problems of the cost and durability, etc. Whether highly effective and lowering cost can be done is one of the keys to practical use. Up to now, direct dimethyl ether fuel cell (DDFC) that used DME as a fuel in polymer electrolyte fuel cell (PEFC) has been being researched. The research on the catalyst in them was to have done the optimization by changing the catalyst quantity of the anode or the cathode. Then, the purpose of this research is to improve the performance of DDFC without changing the catalyst quantity. The structure of the catalyst is changed by adding the glycerin when the catalyst seat is made, and the fuel often comes in contact with the catalyst and the performance is improved. The made glycerin addition catalyst is used for either of the anode or the cathode.

A balance between industrial pollution and economic growth becomes a major policy issue to attain a sustainable society in the world. To discuss the problem from economics and business perspectives, this study proposes a new use of DEA (Data Envelopment Analysis) as a methodology for unified (operational and environmental) assessment. A unique feature of the proposed approach is that it separates outputs into desirable and undesirable categories. Such separation is important because energy industries usually produce both desirable and undesirable outputs. This study discusses how to unify the two types of outputs under natural and managerial disposability. The proposed DEA approach evaluates various organizations by the three efficiency measures such as OE (Operational Efficiency), UEN (Unified Efficiency under Natural disposability) and UENM (Unified Efficiency under Natural and Managerial disposability). An important feature of UENM is that it separates inputs into two categories and unifies them under the two disposability concepts in addition to the proposed output separation and unification. This study incorporates an amount of capital assets for technology innovation, as one of the two input group, into the measurement of UENM. Then, it compares UENM with the other two efficiency measures. This study is the first research effort in which DEA has an analytical capability to quantify the importance of investment on capital assets for technology innovation. To confirm the practicality of the proposed approach, this study applies the three efficiency measures to a data set regarding manufacturing and non-manufacturing industries of 47 prefectures in Japan. This study empirically confirms the validity of Porter hypothesis in Japanese manufacturing industries, so implying that environmental regulation has been effective for betterment on the performance of Japanese manufacturing industries. Another important finding is that the emission of greenhouse gases is a main source of unified inefficiency in the two groups of industries. Therefore, Japanese industries, examined in this study, need to make their efforts to reduce the greenhouse gas emissions and air pollution substances by investing in capital assets for technology innovation.

The concept of resilience is a crucial part in crafting visions of desirable futures designed to withstand the widest variety of external shocks to the system. Backcasting scenarios are widely used to envision desirable futures with a discontinuous change from the present in mind. However, less effort has been devoted to developing theoretical frameworks and methods for building backcasting scenarios with a particular focus on resilience, although resilience has been explored in related sustainability fields. This paper proposes a method that helps design backcasting scenarios for resilient futures. A characteristic of the method is to delineate “collapse” futures, based upon which resilient futures are described to avoid the various collapsed states. In the process of designing backcasting scenarios, fault tree analysis (FTA) is used to support the generation of various risk factors and countermeasures to improve resilience. In order to test the effectiveness of the proposed method, we provide a case study to describe resilient energy systems for a Japanese community to 2030. Four expert workshops involving researchers from different disciplines were organized to generate diversified ideas on resilient energy systems. The results show that three scenarios of collapsed energy systems were described, in which policy options to be taken toward achieving resilient energy systems were derived.

Abstract A novel process for carbon dioxide (CO 2 ) separation, which was named a membrane flash process, was developed to realize an energy-saving technology and to substitute it for a conventional regenerator. The electric energy for CO 2 recovery in a membrane flash process using aluminum oxide and diethanolamine was lower than the thermal energy of the conventional chemical absorption process. Flashing at elevated temperature by the low temperature energy significantly reduced the electric energy and required much less membrane area. This process has potentiality of low cost capture of CO 2 when the low temperature energy, which is not available for other purposes, can be utilized to elevate flashing temperature.

Abstract The drive to achieve low emissions from gas turbines has been an ongoing challenge for over 30 years with the reduction of NO x levels representing the most difficult issue. Catalytic combustion represents the technological approach that can achieve the lowest level of NO x , in the range of 3 ppm and lower depending on the combustion system design. The program to develop a catalytic combustion technology that can achieve ultra low levels of NO x , CO and unburned hydrocarbons (UHCs), applicable to a wide range of gas turbine systems and with long term durability is described. The technological approach is to combust only a portion of the fuel within the catalyst with the remaining fuel combusted downstream of the catalyst allowing the catalyst to operate at a low temperature and thus obtaining good long term catalyst durability. This catalytic combustion approach is then applied to a 1.4 MW gas turbine to demonstrate feasibility and to obtain real field experience and to identify issues and areas needing further work. The success of this demonstration lead to a commercial combustor design. This combustor and the final commercial package is described and the performance specifications discussed.

Bifunctional star-burst amorphous molecular materials displaying both efficient solid-state luminescence and high hole-transport properties are developed in this study. A high external electroluminescence quantum efficiency up to 5.9% is attained in OLEDs employing the developed amorphous materials. It is revealed that the spontaneous horizontal orientation of these light-emitting molecules in their molecular-condensed states leads to a remarkable enhancement of the electroluminescence efficiencies and carrier-transport properties.

A simulation of solar hydrogen generation with solar modules and PEM cells in consideration of the solar module temperature for one year was carried out using our measured weather data. The optimal combination of the number of PEM sheets and solar modules was determined and hydrogen conversion efficiency was estimated. Solar module temperature was predicted from the measured data of global solar radiation, ambient temperature, and wind velocity. The current-voltage (I-V) curves of a solar module in arbitrary states were calculated from the (I-V) curves in the reference states using conversion equations (JIS C8913).

Proton conducting ceramics (PCC) cells are promising energy conversion devices that enable high efficiency energy conversion at lower temperature range, solving the challenge of conventional solid oxide cells (SOCs) due to the high operating temperature. Electrochemical performance and chemical stability of PCC electrolyte has been investigated in recent studies, suggesting that rare-earth doped Ba(Zr,Ce)O3 perovskite-type ceramics are optimal materials exhibiting high proton conductivity and chemical stability during operations. On the contrary, mechanical stability of these PCC electrolyte materials has not been evaluated despite the fact that the mechanical properties are critically important for achieving long-term stable operation as fuel cells or electrolyser cells. For the development of conventional SOCs, mechanical stability during high temperature operation was one of the most significant challenges to deal with, which was attained as a result of detailed studies on in-situ elastic properties of composing materials such as oxygen ion conducting electrolytes and residual stresses. Similarly, for PCC cells, mechanical properties of cells and composing materials have been of significant interest in order to achieve mechanically stable long-term operation, even though PCC cells operate at lower temperature than SOCs. Furthermore, the metal-supported (MS) structure which provides superior mechanical robustness compared to anode-supported (AS) structure is expected to be applied effectively to PCC cells, which are called proton conducting ceramics – metal-supported cells (PCC-MSCs), leading to greater necessity of the mechanical evaluation of the cells and composing materials. Electrolyte is the most crucial component in an electrochemical cell and must be mechanically stable because ion transport and gas tightness made by electrolyte determines electrical performance. However, there has been important concern that larger thermal stresses might be introduced in PCC cells compared to SOCs, resulting from the thermal expansion coefficient (TEC) mismatch between the electrode and electrolyte and from the chemical expansion by the hydration that occurs in a certain temperature range. The PCC electrolyte is highly in need of investigation on in-situ mechanical properties, especially on elastic properties. In this study, elastic properties of electrochemically promising PCC, Y-doped Ba(Zr,Ce)O3 perovskite-type ceramics, were investigated under high temperature conditions. Elastic moduli such as Young’s modulus and Poisson’s ratio were measured by the method that we previously developed for elastic investigation in high temperature conditions using ultrasonic waves. This method enables highly accurate and repetitive examination of elastic properties at high temperatures in materials with poor sinterability including PCC by measuring ultrasonic sound velocities in pellets typically fabricated for electrochemical tests. Pellets of BaZr1-xYxO3-δ (BZY) with different concentrations of doped yttrium, BaZr0.9Y0.1O3-δ (BZY10), BaZr0.85Y0.15O3-δ (BZY15), and BaZr0.8Y0.2O3-δ (BZY20), were fabricated. Additionally, pellets of BaZryCe1-yY0.1O3-δ (BZCY) with different ratio of Ce to Zr, BaZr0.7Ce0.2Y0.1O3-δ (BZCY721) and BaZr0.8Ce0.1Y0.1O3-δ (BZCY811) were fabricated. Powders of PCCs above were consolidated to be thick rounded shape and sintered in air. Each prepared sample was set in an electric furnace in laboratory air atmosphere and sound velocities were measured with the sample slowly heated up to 700 °C and subsequently cooled down to room temperature to calculate elastic moduli at each measuring point. In the first series of heating and cooling measurements for as-sintered samples, hysteresis on elastic moduli in intermediate temperature range was observed. We repeatedly conducted a series of heating and cooling measurements several times, and then the hysteresis was not observed any further. Fig.1 shows final state Young’s modulus of BZCY721, BZCY811, and BZY10 (BZCY901) without hysteresis. Elastic moduli at room temperature have not changed through multiple heating and cooling measurements, and crystal structures and lattice parameters were also confirmed to remain constant by x-ray diffraction (XRD) analysis. The hysteresis found in a specific temperature range suggests that elastic moduli were influenced presumably by a change in defect structure of PCC caused by hydration or defect association of oxygen vacancies and dopants. At room temperature, Young’s modulus decreased with the increment of Ce concentration by 16 % from BZY10 to BZCY721. When materials have the same crystalline structure, Young’s modulus generally decreases as mean atomic volume of the base crystal increases. Because BaCeO3 has larger mean atomic volume than BaZrO3, this observation is qualitatively reasonable. However, in high temperatures, the difference became significant only for BZCY721, Young’s modulus decreased by 30 % from that at room temperature in BZCY721. These results suggest that Ce substitution causes different high temperature dependences. Figure 1

AbstractCatastrophic fires occurred in Australia between 2019 and 2020. These fires burned vast areas and caused extensive damage to the environment and wildlife. In this study, we estimated the carbon dioxide (CO2) emissions from these fires using a bottom-up method involving the improved burnt area approach and up-to-date remote sensing datasets to create monthly time series distribution maps for Australia from January 2019 to February 2020. The highest monthly CO2 emissions in Australia since 2001 were recorded in December 2019. The estimated annual CO2 emissions from March 2019 to February 2020 in Australia were 806 ± 69.7 Tg CO2 year−1, equivalent to 1.5 times its total greenhouse gas emissions (CO2 equivalent) in 2017. New South Wales (NSW) emitted 181 ± 10.2 Tg CO2 month−1 in December 2019 alone, representing 64% of the average annual emissions of Australia from 2001–2018. The negative correlation observed between CO2 emissions and precipitation for 2001–2020 was 0.51 for Australia. Lower than average precipitation and fires in high biomass density areas caused significant CO2 emissions. This study helps to better assess the performance of climate models as a case study of one of the major events caused by climate.