A Plug-in hybrid electric vehicle (PHEV) is a kind of hybrid electric vehicles, which can be charged from the electric grid and can provide several ten kilometers of all-electric driving range. Due to recent introduction of hybrid electric vehicles and development of advanced batteries such as the lithium-ion battery, PHEV is expected as a good candidate to reduce oil consumption and CO2 emission in Japan. The purpose of this study is to analysis the economic advantage and ecological effects of PHEV in Japan considering utilization patterns and electricity supply mixture. The results are as follows: (1) Considering the utilization patterns of passenger vehicles in Japan, PHEV with 35 kilometers of all-electric driving range could reduce oil consumption by 58 % compared with HEV. (2) When the total of vehicle cost and discounted fuel cost is minimized, the PHEV will become widespread after 2010, and it will account for 80% of all passenger vehicle market after 2030. (3)In the case of (2), it will reduce CO2 emission by about 57 million t-CO2 in 2050 compared with that of all gasoline vehicles in 2050.
It is very important to use low-rank coals for Japanese coal-fired power stations from the view points of energy security and fuel cost. Three kinds of Upgraded Brown Coal (UBC) were fired in a pulverized coal combustion test furnace (thermal input of fuel: 760kW) in this study. Gas compositions at the furnace outlet and unburned carbon in fly ash were measured. The results were compared with those of coal combustion tests. The relationship between two-stage combustion ratio and NOX concentrations on combustion of UBCs are different from that of a bituminous coal combustion, because NOX concentrations on non-staged combustion of UBCs are lower than that of the bituminous coal combustion. The unburned carbon concentration in fly ash on the bituminous coal combustion increases with increase in two-stage combustion ratio. Those on combustion of UBCs are, on the other hand, almost constant, when two-stage combustion ratio is changed. The NOX conversion ratios (NOX concentration at the furnace outlet / NOX concentration when all the nitrogen in the fuel converts into NOX) of UBCs are lower than those of coals. The combustion efficiencies of UBCs are almost same with those of coals.