Power System (Grid) Stabilization and PtoG Hydrogen

Abstract

As for the methods to obtain regarded low-cost CO₂ free hydrogen inside Japan, hydrogen productions from unutilized energy such as surplus power of VRE s (Variable Renewable Energy) are important to be taken up. Where the hydrogen generations have random fluctuations, and to meet the confirmed hydrogen demand, insertion of hydrogen storage systems before shipment of hydrogen is required. Such storage costs become significant.

In case of substantial raise in VRE supply surplus is expected to occur, and addition of new demand, such as water electrolysis, is adoptable for maintaining the demand-supply equality (power system stabilization). This is called surplus VRE PtoG-Hydrogen.

In Hokkaido, if introduction of VRE became 17.8% of yearly electric power amount, with the same time-pattern variations in 2016 fiscal year, quantity of hydrogen yearly produced due to surplus VRE PtoG would be 520 million Nm3 and the hydrogen seasonal storage before shipment with inventory turn-over-number of 1 would be required.