Kazuo Takahashi

Specialty : Environmental chemistry based on chemical thermodynamics and reaction kinetics

Research Theme : Research and development of engine combustion technology aiming for ultimate thermal efficiency through carbon recycling and carbon-free next-generation automobile fuels and chemical reaction control

Most automobiles today run on fossil fuels such as gasoline, diesel, and natural gas in their internal combustion engines. However, to solve global issues such as global warming and the associated climate change and depletion of fossil resources, automobiles must also respond to these issues. Japan has set a goal of reducing greenhouse gas emissions by 46% compared to 2013 by 2030 and achieving net zero (carbon neutral) by 2050. There are various approaches for the automobile industry to achieve this goal, and it is not yet definitive, but our research group is trying to achieve this by changing the fuel burned in conventional internal combustion engines.

To reduce or virtually eliminate carbon dioxide emissions from automobile engines, it is necessary to conduct research from two perspectives: 1) developing new fuels and 2) improving the thermal efficiency of automobiles. Carbon dioxide produced by combustion can be captured and reduced with hydrogen produced from renewable electricity to regenerate fuel (carbon-recycling synthetic fuel, e-fuel), or these capture and reduction processes can be carried out with the help of plants (photosynthesis) (biofuel), so carbon dioxide will not increase further even when a car is running. In addition, when ammonia, which has recently been attracting attention as an energy carrier for hydrogen, is burned as fuel, it does not emit carbon dioxide because it does not contain carbon.

If such carbon-recycled fuels or carbon-free fuels are used as automobile fuel, greenhouse gas emissions from automobiles can be reduced to virtually zero, but the manufacturing costs of these fuels are naturally higher than those of fossil-derived gasoline and diesel. In order to absorb this higher cost, the thermal efficiency (fuel economy) of automobiles must be improved. In addition to developing the next-generation automobile fuel mentioned above, we are also conducting research to improve the thermal efficiency of automobile engines from the current 40% to 60% by controlling reactions using a special device called a high-pressure shock tube, which can track chemical reactions during engine combustion.