Life of energy infrastructures such as power generation plants and petroleum refineries is more than 40 years, and it takes long time for changing over technology generations. For studying the future energy infrastructure, it is required to consider several aspects: change of supply conditions of primary energies, change of energy conversion technologies and change of demand side of secondary energies. According to the energy outlook of Japan, dependency on petroleum will be reduced while requirement for electricity will be increased. Availability of light crude oil will become tight while demand for lighter products will increase relatively with less demand for heavier products. This means it is crucial to adopt some technologies for processing heavy bottoms. We constructed an integrated model including grid power generation system and petroleum refining system to study the change of energy conversion sectors. It is a multi-period linear programming model covering 2000 to 2050. Gasification technologies, such as Resid IGCC and Gasification Hydrogen Unit, are introduced as bottom processing technologies in addition to conventional thermal and hydro cracking. We found following results: (1) Using only heaviest crude oil, lighter products can be supplied by cracking facilities, while residues are fed to power generation then exported to power grid. (2) Potential of electricity generated by Resid IGCC is about 5% of total Japanese power demand, with generation capacity 7GW. (3) Hydrogen unit is also converted from conventional steam reformer using light feed stocks to gasification hydrogen unit using thermal cracked residues.
