The decrease of the enzyme cost is an important problem for cellulosic ethanol production, so this study considers the enzyme recovery process to decrease the enzyme input. The process which the enzyme was not recovered and the enzyme recovery process by the Membrane Separation (MS) and the Reduced-pressure Distillation (RD) were simulated, and the material and the energy balance were calculated. The cost of each process was calculated based on the simulation results, and the economic advantage of the enzyme recovery process was evaluated. On condition of 10 FPU/g-biomass and 400 FPU/g-protein, even if the enzyme price was reduced from 1000 yen/kg-protein (bulk buying of a tanker scale) to 300 yen/kg-protein (on-site production), it became clear that it is economically more advantageous to apply an enzyme recovery process. In MS process, although an enzyme recovery rate is high, the equipment depreciation expenses become large. In RD process, although an enzyme recovery rate is low because of enzyme deactivation, there is little additional cost. By these results, the cost of MS and RD process became comparable.

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The objective of this research is to develop the measures to promote energy saving based on monitoring of energy and other factors by using wireless sensor nodes. In the current research, power consumption monitoring at eight convenience stores (CVSs) for a year and half (from July 2010 to February 2012) was undertaken. This paper addresses two themes on power saving at CVSs. First, the evaluation scheme of power saving practices at CVSs is explored. We present an estimation model for power consumption at CVSs. Since the amount of daily power consumption at CVSs is strongly correlated to the external temperatures, an estimation model using external temperature as the parameter is developed. The effectiveness of the models and the application of the models to evaluate power saving in 2011 with regard to in 2010 at the monitored CVSs are presented. Second, we present results of assessing the effectiveness of some power saving measures at CVSs. Power saving measures at usages of air conditioners and cooking fryers were assessed. Summarization of other measures is also presented. We show that monitoring for at least five days at each CVS enables us to obtain evaluation models.

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Although a large body of research on the price elasticity of energy demand in Japan already exists, the elasticity estimates have wide range of results. Two problems most commonly noted in connection with estimating the price elasticity of energy demand concern the influence of non-linier energy demand trend and the asymmetry of price elasticity when prices rise and fall. Taking these two issues into account, we estimate the energy demand function for eight industrial sectors in Japan.
As for energy intensive sector, we found that the price elasticity in the period of price rise is higher than that of price fall. The estimated price elasticity is not very high, the lowest is -0.05 and the highest is -0.41. When we estimate time-varying price elasticity with single price variable without considering the asymmetry, the estimated price elasticity tends to change over time. However our results show that the asymmetric price elasticity is rather constant during the period even we use the time-varying parameter model. Therefore, the change of price elasticity is not reflecting the demand structural changes but is influenced by directions of price change.

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