Fukushima Prefecture aims to cover 100 % of its energy demand with renewable energy sources by 2040. Due to fluctuations in renewable energy power generation caused by weather conditions and other factors, a gap between power supply and demand tends to occur when renewable energy power plants are connected to the grid. In the future, this gap is likely to lead to the generation of a large amount of surplus power. Hydrogen can be produced by electrolysis of water using this surplus power. Large quantities of hydrogen can be stored in tanks through compression, liquefaction, or chemical conversion. The hydrogen can be converted back into electricity using a generator or used as a fuel for other applications such as automobiles.

The researchers, in collaboration with Hitachi, Ltd. and Denyo Kosan Co., Ltd., have demonstrated supply chain technology for producing hydrogen using renewable energy power promoted by Fukushima Prefecture, chemically converting, storing and transporting it, and generating power with a hydrogen co-firing engine generator system. In this supply chain, toluene is chemically converted into methylcyclohexane (MCH), a hydrogen energy carrier, using the hydrogen produced with renewable energy. They have developed a hydrogen energy carrier production system with a simple configuration. The hydrogen co-firing engine generator system ran for more than 1,000 hours in total, producing 300 - 500 kW at a hydrogen energy share ratio of 40 - 60 %.