BTL is advocated to be widely introduced in near future (by 2030) by Japanese government. BTL synthesis is now R&D stage in Japan and its development is urgently required. We have been studying the gasification of biomass using an entrained-flow type gasifier and clarifying the suitable conditions for synthesizing liquid fuels in the joint researches with companies and universities organized by the New Energy and Industrial Technology Development Organization (NEDO) biomass projects, those are, methanol synthesis in a 2 ton/day scale test plant, bio-LPG synthesis and bio-jet fuel synthesis. We introduce and overview woody and herbaceous biomass gasification and BTL synthesis using an entrained-flow gasifier in Japan.

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Photovoltaic (PV) generation has attracted much attention as a new electric-power generation system. However, the output power of PV generation systems experiences significant fluctuations, which negatively affect the electric-power reliability of the grid. It is therefore necessary to smoothen it using power-smoothing control methods. This paper evaluates different power-smoothing control methods using a moving average filter and finite impulse response filters for distributed generation systems with energy storage devices. We analyze the gain and phase characteristics of these filters, and we perform computer simulations to evaluate the effectiveness of the smoothed electric power generated by PV generation systems.

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To promote the utilization of biomass energy, it is important to evaluate the potential resource and its distribution and accessibility appropriately. In this study, the available amount of various kinds of biomass resources was estimated based on several statistical data. These data are aggregated into the geodatabase with a uniformed and fine spatial resolution of 1km mesh by estimating its spatial distribution using geographic information system (GIS). Furthermore, the accessibility analysis was performed by the GIS-based network analysis based on the real road network in each region. As a result, the relationship between the accessible time and the resource potential was figured out in each region by this method. Moreover, the transportation costs of each resource were estimated by applying a cost condition. For instance, in Furano City, thinning woods have the highest potential in the entire region. However, crop residues have higher potential in the region accessible from the municipal office as a demand site within 20 minutes. Also, crop residues are considered more reasonable than the others throughout the region in terms of transportation costs.

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The biogas production of seaweed is commonly patterned to conventional digester wherein the anaerobic condition is optimized for terrestrial biomass. The high salt content of seaweed and its different structural component than terrestrial plants may contribute to low conversion efficiency. Hence, freshwater (FW) and thalassic (TH) anaerobic digestion of Ulva species were compared to determine the more suitable condition. Biological hydrolysis pretreatment (BHP) was done to improve methane yield, while NaOH pretreatment (CNP) was employed to minimize the limitation of biological hydrolysis. Higher biogasification efficiencies based on the theoretical methane yield (285.23 mL CH4/g Volatile Solids [VS]) were obtained using biological hydrolysis pretreatment (FW: 27.23%, TH: 63.42%). However, the biogasification time of BHP was twice as long as that of NaOH. Nonetheless, the methane yield of all pretreatments under thalassic (BHP: 180.9 mL CH₄/g VS, CNP: 158.19 mL CH₄/g VS) was higher than freshwater’s (BHP: 77.66 mL CH₄/g VS, CNP: 61.67 mL CH₄/g VS), suggesting a superior methane fermentation under thalassic condition.

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Improvement of reaction system for the fixed bed high quality biodiesel (HiBD) production has been investigated. When the HiBD production, catalytic cracking of waste cooking oil over a MgO/SiO₂ catalyst, was conducted with a conventional down flow type fixed bed reactor, yield of oil (C4-C18hydrocarbons) obtained at 450 °C was 55% with a large amount of C19+ oxygenated compounds (about 30 %). On the other hand, the oil yield at 430 °C with an up flow type reactor was higher (above 60 %), and the oxygenates yield decreased. Addition of water to the reactant oil in the form of emulsion was found to promote the hydrolysis of triglycerides to free fatty acids and the oil yields also improved for both down flow and up flow reactors. In the latter case, although yield of oxygenates increased compared without water, acid value did not increase. These findings show that the up flow type reactor is suitable for the formation of HiBD using a fixed bed reaction system.

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