The Feasibility of Solar Energy Supply for Japan in the 21st Century

Abstract

Japan can obtain main energy from sun light in the 21st century. This is because, first, the cost of solar electricity produced in Japan, about ¥21/kWh, is competitive with that of oil-fired power plants if the cost for environmental damage is considered. The capacity of solar electricity within the land is estimated to be 509 GW and one third of this amount can be installed by 2010 to replace the 59 % increase of the supply of nuclear electricity planned to enable the 6% cut of CO₂ emission according to the COP3. The rest of the capacity can serve to cut the capacity of nuclear-and/or fossil-fueled power plants further. Second, the cost of the solar hydrogen including the cost of pipeline tranport from the sun-belt region is estimated to be ¥18-23/Nm³ ($12-18/GJ), the cost of electricity from fuel cells supplied with solar hydrogen to be ¥17/kWh for the cheapest case around 2010, and both are also of competitive prices. Regarding the amount of solar and wind resources in Asia and Australia, we postulate that Japan should design the import of necessary energy to replace fossil and nuclear energy probably with an amount between 20 and 34 EJ/yr of hydrogen for the period 2000-2050.