The Blue Tower (BT) process has a characteristic of producing the high concentration H₂ gas. So far, we have executed some experiments in order to estimate gaseous yields through BT process. In the previous studies, we confirmed that the biomass material such as woody chips (Japanese Cedar etc.) was more adequate for the production of Bio-H₂ fuel. However, from the viewpoint of LCA (Life Cycle Assessment) thinking, the specific CO₂ emission and energy efficiency of Bio-H₂ were 57.0 g-CO₂/MJ and 1.14 MJ/MJ, respectively. This implies that the energy input of the auxiliary is affected of fossil fuel origin to much extent. That is, in this process, the improvement of the environmental indexes is to reduce fossil fuel consumption in the plant which is counted as the auxiliary power.
In this study, we proposed the innovative process through CO₂ adsorption system. We focused on the adsorbent of “HAS-clay”, which has a characteristic of adsorbing CO₂ at the room temperature. Based on the performance data on “HAS-clay”, we compared the environmental indexes of Bio-H₂ in the conventional process to ones in the proposed way.
As a result, we estimated that the Bio-H₂ production rate was 304.8Nm³/h and the auxiliary power was 180.6 to 202.6 kW, Also, the energy intensity of 0.94-1.01 MJ/MJ-fuel and the CO₂ emission of 49.5 to 52.0 g-CO₂/MJ, respectively.

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This paper aims to forecast the demand of dysprosium (Dy), a rare earth element, which being broadly used in automobiles, home appliances, HDD, etc, using ratio of dysprosium-carrying end-use products, weight ratio of dysprosium in end-use products, production of end-use products. Moreover, the new methodology was proposed and evaluated, which able to estimate quantitatively the influence of the strategies, for example, changes in recycling ratio or Dy ratio in end-use application. From the result, 740-780 (t/y) of domestic Dy demand was forecasted to be reduced, by producing Dy less permanent magnet and recycling in 2030.
This new method was validated by evaluating the relationship between the future scenario of the Dy-less strategy, and domestic Dy demand forecast. The result of this paper evidently confirms that Rare Earth demand forecast for each end use products is useful for strategy making of critical material security.

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Energy demand will change in the structure due to population declining and aging. Communities where residents are not moved dynamically are more vulnerable to the problems. The energy demand transformation could shift the suitable energy system for residences and communities in long-term.
This study is aimed at establishing a simulation model to estimate hourly and seasonal energy demands at a residence and in a community in the coming 50 years. In the estimate, we took three steps. First, we developed a population and family dynamics model to generate profiles of people and families. Next, we simulated the members’ actions for each family. Final, from the family members’ actions, we estimated energy demand inside and outside the house and for traveling.
The estimate result shows energy demand at a residence where currently young parents and children live will decrease around 30 percent until 2060 due to family members’ aging. While this decrease is not significant for the family itself, energy service companies, residential developers, and governments should consider its impact.

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