We conducted a survey of two plywood factories that differ in production scale for the purpose of researching and evaluating the environmental impact they have. One plant (plant A) is a smaller scale factory and treats plywood made from imported and domestic timber, the other plant (plant B) is a larger scale factory that treats plywood made from only domestic timber. We calculated the yield and measured the energy used at the plywood mill. Then we calculated the CO₂ emissions per cubic meter from plywood production. We compared the CO₂ emissions during the production of one cubic meter of plywood in two different production scale plants. The CO₂ emissions per cubic meter of plywood production from plant A was 180kg-CO₂/m³, the CO₂ emissions from plant B was 190kg-CO₂/m³. The difference of the CO₂ emissions from the manufacturing process is large, but the diferrence of of the CO₂ emissions of total is not so large.
Finally, we calculated the difference of the environmental impact when constructing a detached wooden house by using two different plywoods from two different production scale plants. The difference is 0.380t-CO₂.The difference is not so large.

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This paper considers the introducing possibilities of the hydrogen system in the aspect of cost-benefit performance, where the produced hydrogen from surplus electric power of PV is stored and it generates power as hydrogen mixed fuel.
Recently, the realization of a low carbon society has been becoming a common view of the world. In the case of Japan, renewable energy sources have been increasingly installed since the Feed-in Tariff scheme was introduced.
On the other hand, it is anticipated that the power system operation will be problematic with the growing number of RES being installed. Therefore, in order to install a large number of RES to promote further realization of the low carbon society, it will be essential to conceive some new methods for the power system operation and effective utilization of surplus electric power.
One of the candidate approaches is hydrogen electric power storage. A characteristic of hydrogen electric power storage is that the two phases which are producing hydrogen from electric power and generating electric power with hydrogen can be separated. Whereas a pumped storage power plant or a battery cannot charge and discharge electric power simultaneously, in use of hydrogen these tasks are concurrently executable.
In this paper consequently, we illustrate an economic analysis of the use of surplus electric power of RES by means of hydrogen production and hydrogen storage in conjunction with multi fuel combustion using the hydrogen by thermal power generation equipment.

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A congestion at quick chargers (QCs) which increases the total travel time of EVs has occurred due to a massive spread of electric vehicles (EVs). In order to reduce this congestion, it is necessary to grasp the actual charging behavior of EVs and consider its measures. In this report, secular change of EV quick charging and its charged electricity amount were analyzed using 412 thousand charging histories from 2012 to 2014 by 509 QCs in Japan. The secular changes of charging revealed the decrease of charged electricity amount, the seasonal fluctuation of charging time, and the frequency of use. Analysis using the idle time of QCs showed that the charged electricity amount increases and decreases due to the congestion of chargers. When QC is crowded, the charged electricity amount by EVs increases on a highway and decreases on a general road. When the use of QC decreases, the charged electricity amount by EVs shows almost the same distribution for both highway and general road. It is assumed that the judgment on the necessity of charging by EVs is not influenced by the road type. In addition, the change of the charged electricity amount caused by the congestion and the road type was also discussed.

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Marine biomass such as seaweed and fishery waste is a potential energy source although it has not yet been practically utilized. This study focuses on anaerobic digestion for the utilization of various organic wastes as energy resources. We introduce marine biomass utilization system, which consists of biomass transportation, anaerobic digestion, and energy conversion, and propose two scenarios considering seasonal change of available biomass. The purpose of this paper is to understand digestion characteristics of mixed biomass (seaweed, fishery and vegetable waste) through continuous-processing experiments. And also we investigate feasibility from the economic and environmental viewpoints. The results of the economic analysis indicate that it is not feasible even Feed-in Tariff is considered. The main income is the charge of waste biomass treatment, varying with local governments. From an environmental viewpoint, produced electricity and heat from methane gas contribute to reduce fossil fuels. These results would contribute to design anaerobic digestion system with marine biomass.

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