Introduction

Photovoltaic power generation is one of the promising processes for the achievement of a clean energy production system.  However, its power supply depends on weather, daylight hours, and solar radiation intensity.  This drawback interrupts the establishment of a social system based on solar energy.  For developing an eco-friendly sustainable society, other power generation technologies as well as the photovoltaic power generation should be employed for a desirable and highly efficient power generation system.  This combined power generation system, named as “Hybrid Power Generation System”, would be a key program to build the eco-friendly sustainable society in near future.

Researches

In the department of “Hybrid Power Generation System”, the following three research areas are considered to be key technologies.

I.       Fuel Cells

II.      Environmental load-reducing technology

III.    Environment impact assessment

 

Fuel cells

Fuel cells are one of the technologies in spot light as a next-generation power device. Generally, fuel cells generate electricity by the chemical reaction of hydrogen and oxygen in air.  Hydrogen is considered as one of the cleanest energy sources since it can produce only water as an exhaust gas.  For the practical use of fuel cells, the highly purified hydrogen is necessary.  Therefore, the production, separation and purification techniques of hydrogen are the key technologies in this research area.

 

Environmental load-reducing technology

Conventional power plants using fossil fuels, e.g. a thermal power station, should be integrated with the clean energy system to maintain stable electric power supply.  In many cases, however, their operations are not eco-friendly because these conventional power plants emit hazardous substances as well as a large amount of CO₂ which is the main part of greenhouse gas.  Hence, flue gas treatments such as denitrification and CO₂ capture and storage should be provided to the power plants for the establishment of the hybrid power generation system.

 

Environmental impact assessment

For the commercial use of noble materials and technologies, environmental impact should be predicted before they are used in practice.  Thus, the feasibility study on various technologies concerning a clean energy around photovoltaics will be conducted based on the life cycle assessment.

Noted that the hybrid power generation system should consider the most suitable combination of many elemental power generation technologies in the whole system where photovoltaics are the central technology.  We contribute to realize the eco-friendly sustainable society in near future through the research and development of such the hybrid type generation system.

Hybrid Power Generation System

Hybrid power generation system is the combination of plural generation technologies in the most suitable form, and it will become a next-generation power generation system with minimum environmental load.

 

Highly Efficient Hydrogen Production System (Membrane Reactor)

A membrane reactor is the combined reaction system consisting of steam reforming reaction and hydrogen-selective membrane separation.  Our adopted membrane can produce extremely pure hydrogen (>99.99%) from natural gas and petroleum fuels in only one unit operation with extremely low energy consumption.