Renewable Energy is the Key to Reconstruction of Japanafter the Great East Japan Earthquake/Tsunami
Masayuki Kamimoto
Vice Chair, JCRE
North Japan Research Institute for Sustainable Energy, Hirosaki University

Present energy situation in JapanThe Great East Japan Earthquake/Tsunami on March 11 and the subsequent severe accident ofFukushima Nuclear Power Plant revealed the vulnerability of the present energy systems. Safe
shutdown of the reactors and secure power supply during the summer peak season are thepresent major concern. To cope with the power shortage, the target of power use restriction hasbeen decided to be set at 15% of last year’s peak demand level. Households are requested tosave as much power as possible.
Importance of renewable energy has increased
From medium- and long-term view points, the existing “Strategic Energy Plan of Japan” will beoverhauled, since it strongly relies on much electricity supply by nuclear power plants.
Although it is not an easy task to find a solution to the trilemma between energy supply,
environmental protection and economic growth with less nuclear power than originally planned,
at least we can say that introduction of renewable energy and clean distributed energy systems
should be accelerated through R&D and policy measures. The increase of the share ofrenewable energy leads to diversification of the primary energy resources, resulting in not only
CO2 reduction but risk avoidance of the energy networks.
Affluent renewable energy and high heat demand in Northeast Japan
Resource potentials of various renewable energies are different from location to location as wellas the energy demand. The optimum energy system should be constructed and operated
depending on the available energy resources and energy service demand in each location. The
disaster area, northeast Japan, is well known for abundant renewable energy resources such as
wind, biomass and geo-thermal heat. Aomori Prefecture, the northern end of this area, forexample, has more renewable energy potential than its energy demand. The area is also known
as a cold and snowy region, and it has a lot of heat demand especially in winter time: 70 to 80 %share of the total energy consumption of households.
Compact city and national and global grids
Renewable heat (geothermal, solar and biomass) should be utilized as much as possible to meetthe high heat demand in the region and to reduce the electric power consumption for heatgeneration. Fuel cell systems using bio-fuel are other options. So-called “Compact City” will beideal for the effective use of energy, particularly heat. Its size should be decided from various
points of view and the transportations between the compact cities should also be environmentallyfriendly. If we could use renewable heat (geo-thermal, biomass and solar thermal) effectively inthis area, more renewable electricity by PV and wind can be transmitted to the regions withhigher electricity demand such as Tokyo. Much electric power transmission between different
electric power companies will require reinforcement of the national power grid in future, whichshould be more efficient with HVDC transmission or superconducting transmission. The
reinforced power grid can be connected to the future global super-grids. Smart management ofintegrated energy network including electricity, heat and gas is important as well. Renewableenergy technology will play a key role in such future energy systems that it can activate the localindustries. It is thus the key to reconstruction of Japan, particularly in the disaster area.