Issues in microalgae biofuel production and efforts to solve them（2nd Report）

Shinichiro Maeda･Kazuo ichikawa･Takehisa Koroki･Hiromi Tanaka (Mazda)･Kumiko Okazaki (Hiroshima University)･Yoshitaka Nishiyama (Saitama University)･Satoshi Nakai･Takashi Yamamoto (Hiroshima University)･Hiroyuki Ota (Phytolipid Technologies Co., Ltd.)･Atsushi Sakamoto (Hiroshima University)

Microalgae biofuels, characterized by high productivity and non-competition with food resources, are regarded as promising candidates for next-generation carbon-neutral liquid fuels. Mazda has been conducting research on fuel production using the marine microalga Nannochloropsis through industry–academia collaboration. Previous reports have described the modeling of processes from cultivation to fuel production, the identification of bottleneck areas, and efforts undertaken to resolve them. This paper reports on the identification of bottleneck areas in CO₂ emission reduction and presents initiatives that utilize waste energy and waste materials to address these challenges.

Evaluation of Base-Fuel Dependence on Ignition-Suppression Effect of ETBE Using a High-Pressure Shock Tube

Ken Satokawa･Tomohiro Hamasaki･Reina Okamura (Sophia University Graduate School)･Kazuo Takahashi (Sophia University)

In order to realize a carbon-neutral society, the phased introduction of biofuels is being considered in Japan. We have previously focused on the ignition suppression effect of ethanol and clarified its dependence on the base fuel. In the present study, we investigated the interaction between ETBE and the base fuels through ignition delay measurements using a high-pressure shock tube, and compared the results with those of ethanol.

LCA Prediction of Lithium-Ion Batteries for Electric Vehicles Based on the Paris Agreement

Keiichiro Sano･Yuuri Ujike (Kanto Gakuin University)･Yasuhiro Oi (Former Kanto Gakuin University)･Hiroshi Yagita (Nippon Institute of Technology)･Junichi Kasai･Katsuhiko Takeda (Kanto Gakuin University)

CO2 emissions during power generation vary from country to country. In this study, based on the Paris Agreement, the LCA was used to predict the reduction in CO2 emissions over lifetime traveling of lithium-ion batteries for electric vehicles up to 2050. It was estimated that, in terms of lifetime use to date, hybrid vehicles are as environmentally friendly as or better than electric vehicles, but that electric vehicles will be better for new vehicles in the future.

Numerical investigation for Onboard Hydrogen Production via Steam Methanol Reforming Using Engine Exhaust

Bhawandeep Sharma･Yuchen Liu (Guangdong Technion Israel Institute of Technology, Shantou , China)･Devendra Yadav･Michael Patrascu (Technion Israel Institute of Technology, Haifa, Israel)･Madan Kumar (Guangdong Technion Israel Institute of Technology, Shantou , ChinaGuangdong Technion Israel Institute of Technology, Shantou , China)

This work investigates alternative fuels, specifically methanol and hydrogen. Given the storage and safety challenges associated with hydrogen, this work focuses on its continuous onboard production via steam methanol reforming, using IC engine exhaust heat as the driving energy source. The approach utilises a catalysed reformer, with exhaust gases routed to enable stable hydrogen production rates of up to 2 kg/h, supporting dual-fuel engine operation. Numerical simulations demonstrate a reliable hydrogen yield suitable for secondary fueling. Future work will experimentally validate the benefits of dual-fuel operation, including improved combustion efficiency and reductions in NOx and CO emissions.