As effectiveness of climate policy is enhanced by nationwide/worldwide implementation, examining the relationship between effectiveness and diffusion of local climate policies is important. This paper takes up a “GHG Emission Reporting System” as one of the well diffused measures among local governments, and clarifies its effectiveness and state of diffusion. A literature survey and interviews to local governments’ officials suggests as follows. Firstly, the system created by Tokyo Metropolitan Government (TMG) has been updated three times. The third one is much more effective than the similar system of the government and the other local governments. Second, the system has been updated partially by the government and some local governments however it has diffused in “degradation” which is minus something from TMG’s system in totally. Thirdly, one of the backgrounds that such state of diffusion comes out is industrial structure. Enough communication with the industrial sector is needed especially for the local governments with high ratio of industrial sector in GHG emission to determine effectiveness and feasibility of the system. Forth, local governments are not necessarily motivated to introduce high effective policy due to carbon leakage until the government prepare a role-sharing arrangement which yield practical benefit for them.

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Solar energy such as photovoltaic or solar heat is promising technology for reducing CO₂ emission. Solar electricity and solar heat are collected in daytime but thermal energy can be conserved easily. This paper describes about energy saving potential of hybrid solar system, which consist of photovoltaic and solar water heater. In this study, we investigated the effect of surface area of solar water heater and photovoltaic at canonical or cold climate area. The simulation results showed us that the 1:0 or 3:2 of surface area ratio of photovoltaic and solar water heater have almost same energy saving effect. The reduction rate of energy demand was 30.4% and 28.9% in the case of 1:0 and 3:2 of surface area ratio respectively. In the canonical climate area, solar water heater can reduce the energy demand for room heating and hot water supply. However, larger surface area of solar water heater brings excess heat supply in the mid or summer season. Therefore, the contribution of solar water heater becomes relatively small compared to photovoltaic. In the cold area, the contribution of solar water heater decreased due to attrition of solar irradiation in the winter season.

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Production of asphalt mixture product discharges 40% of CO₂ emission in the whole road sector in Japan. In this study we developed a new system of asphalt mixture production that uses wood tar instead of fossil fuel. The obtained results are as follows. (1) A system that uses wood tar that comes from biomass gasifier power generation was developed. The wood tar in its high energy density is transported from the site of the power generation to the site of the asphalt mixture production at long distance. (2) A burner technology of asphalt mixture production that uses wood tar at 90% and heavy oil at 10% was developed. The burner system that consists of a binary fluid technique for wood tar and a mono fluid technique for heavy oil keeps stable burning. (3) The high quality of the asphalt mixture product using wood tar was verified. The new system of the asphalt mixture production using wood tar follows the environmental regulations about emission gases. (4) In the case of wood tar at 90% and heavy oil at 10%, the CO₂ intensity from fuel consumption of recycled asphalt mixture production is by 80% less than that in a case at 100% heavy oil.

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In this paper, we have developed a unit commitment model of Japanese electricity market from 2005 through 2007 and checked its validity comparing electricity generation with actual data by each fuel type. Using this model, we estimated marginal costs of electric supply by each of 9 electric companies and identified “sell or buy position” of each company on hourly basis. Then we compared JEPX prices with marginal costs estimated above and examined the reasonableness of JEPX prices. Finally, we simulated hypothetical market within which electric companies are economically rational players, and estimated the potential of electricity trading among market players.

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The effectiveness of consumer collaborations in Asia-Pacific LNG market is evaluated in view of improving supply stability and investment efficiency. LNG demand fluctuates in accordance with the temperature while supply of LNG is rather constant under inflexible purchase contract. Some consumer countries are recently establishing collaborative relations as swapping excessive LNG cargos aiming at reducing gap between LNG supply and demand. The change of demand-supply gap is analyzed through statistical method by using actual 2007 data and the effectiveness of consumer collaboration is evaluated based on the demand-supply gap in 2007. The analysis was also extended to future LNG market in 2030. The result shows that significant benefit is observed for the 2007 analysis as the level of reserve fluctuation is decreased. Furthermore, investment requirement in receiving terminal is reduced. It also shows that the demand fluctuation is still obvious in 2030. The usefulness of consumer collaboration is also shown to be enhanced toward 2030 as the benefits are expanded in most of the countries. The analysis also suggested that exporters can be benefitted from the consumer collaborations through the stabilization of export fluctuations. It means that mutually beneficial relations are possible between consumers and producers in Asia-Pacific LNG market.

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This paper was described about operation results of a 1t/d scale plant of Blue Tower Process which is two stages pyrolyses, 1’st stage is pyrolysis at 550℃, and 2’nd stage is steam reforming at 950℃. Chopped road trees or Japanese cedar chips and/or pellets were fed into the plant as raw materials. It was found that the gaseous low heating value was approximately 11MJ/Nm3 and the concentration of hydrogen was ca. 45 volume %. The energy recovery efficiency on a ratio of Output/Input was maximum 70.4%, and the comprehensive energy efficiency on a ratio of Output/Total input energy which was Input energy + Utility energy was maximum 22.8%.
Next, tar was not observed at inner side of Pyrolyser and Reformer of the plant. It might be said that there would not be few trouble on core components, i.e. Pyrolyser, Reformer and etc. of Blue Tower plant under on a practical use. Also, it was generated a maximum power of 41 kW through the Blue Tower plant operation.
It was simulated about gas component from measured data of the plant, it was concluded that the both data were similar in, so it was possible to be estimate gas components and energy efficiency of commercial plants precisely, by using the simulated data based on the experiment.

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