With the massive introduction of renewable energy sources due to global warming countermeasures and the depletion of fossil fuels, biomass power generation, which is not affected by weather conditions, has been attracting attention in recent years. However, the economic viability of biomass power generation remains a challenge, and its penetration rate remains low. This paper presents an LCA analysis of an energy conversion system using superheated steam gasification and dry methane fermentation gasification, utilizing five types of locally generated resources. Focusing on baseload and peak loads, the impact on business feasibility and the ability to meet electricity demand was evaluated. The results of the case study analysis showed that biomass power generation is feasible in Suita City, but that it is difficult to recover the investment for biomass power generation in Kameoka City. It was also found that base-load operation has a greater business advantage than peak-load operation.

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Better understandings on factors determining electricity demands, and future perspectives on them are important in order to prepare stable and affordable electricity supply. However, there are several and large uncertainties in future electricity demands. The electricity demands for IT including data center are increasing. In addition, electrification is an important option for deep CO₂ emissions reduction. Meanwhile, the relative prices of electricity across countries, and across energy sources will also have large impacts on the future demands. This study analyzes the future electricity demands in Japan up to 2050 through the consistent and quantitative analyses on electricity demands considering several factors by using energy economic models. According to the scenario analyses, the demands in 2050 will be 8-30 % larger than those in 2019. On the other hand, production reductions in energy intensive industries due to implicit or explicit carbon prices are also estimated, and will reduce the electricity demands by up to 4% points.

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In the course of reduction of CO₂ emission, an increasing deployment of variable renewable generation such as PV and wind, whose output largely fluctuate according to weather and time, have been impacting an operation of in many power systems in the world. There are increasing needs for flexibility in all time domains. As the penetration of variable renewable increases, a kind of flexibility to store energy increases and the power system operation is required to cover daily, weekly, monthly and seasonal fluctuations of the generation of variable renewable utilizing a fleet of energy storage technologies. There are many efforts to realize long duration energy storage technologies, in addition to an existing pumped storage hydro, such as some types of batteries, heat storage technologies, and synthetic fuels. This paper presents a development of a methodology to annually optimize, by linear optimization method, the operation of traditional fuel storage and production-storage-utilization operation of new synthetic fuels such as hydrogen and Ammonia. We verified the proposed method in the Hokkaido area in Japan in 2030, as for coal storage for a coal power station, and production, storage and use of a new synthetic fuel produced from renewable energy curtailment.

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