This paper presents a simulation technique of yeast cultivation and ethanol fermentation on a commercially available process simulator. In general, the simulation of microorganism cultivation on the process simulator is not possible because a material data of the microorganism is not registered in the simulator. If all of the data required is collected and installed to the simulator, the simulation of the microorganism cultivation will be achieved on it. Yeast which is a widely known in industrial field was chosen as a model microorganism. The data of yeast was collected by analytical measurement and literature survey, followed by a composition of model yeast and reaction formulas were determined. All data associated the yeast was completely installed in to the simulator. Process of the yeast cultivation and ethanol fermentation was demonstrated on the simulator as a case study. The success of the simulation of the case study was confirmed. Estimation of input substrate quantity and prediction of generated heat amount of microbial reaction become possible on the proposed method. This method can provide diversification and advancement of simulation technique for process evaluation associated microbial reaction.

抄録全体を表示

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 HEVs and development of advanced batteries such as the lithium-ion battery, PHEVs are expected as good candidates to reduce oil consumption and CO₂ emission in Japan. The diffusion of PHEVs would cause the cost reduction of the battery and promote all electric vehicles (EVs). The purpose of this study is to analysis the economic advantage and ecological effects of not only PHEVs but also EVs in Japan considering utilization patterns for vehicle types and the electricity supply mixture. The results are as follows: (1) When the total of vehicle cost and discounted fuel cost is minimized, PHEVs will become widespread after 2010, and EVs will account for 90% for mini-passenger vehicles after 2040. EVs will not dominate in the other vehicle types. (2) In the case of (1), it will reduce CO₂ emission by about 150 million t-CO₂ in 2050 compared with that of all gasoline vehicles in 2050．(3) Additional CO₂ reduction by the introduction of EV is not expected without the increment of zero carbon power generation such as nuclear.

抄録全体を表示

In Japan, the tax cuts and the subsidies on eco-friendly vehicles became effective on April 1, 2009. Due to the schemes, people would renew to a new car prior to the primary life time of a car. Thus, we examined the effect of CO₂ abatement by front-loading replacing vehicles. In particular, we compared the CO₂ reduction due to the improvement of fuel efficiency to the amount of CO₂ increase, whose factors are ‘rebound effect’ and ‘discharge of manufacturing vehicles’. We categorized vehicles into six types, hatchback, minivan, hybrid vehicle (HV), saloon, light vehicle, and others (SUV, convertible). In the case where consumers replace their cars to the following three types (hatchback, minivan, and HV), the CO₂ abatement which divided consumers into household attributes in order to examine difference in expense was estimated. The result showed that a household expenditure would increase due to tax cuts. In addition, if consumers except a single-person household replace their vehicles about 1~10 years earlier than originally plan, there may be no reduction effect when replacing with minivan and/or hatchback. Conversely, the net reduction effect only appears in a single-person household at 1~5 year earlier than originally plan and in case of replacing their cars to HV prior to the vehicle lifetime.

抄録全体を表示

Expanding energy resources for electric power plants from fossil energies to cost competitive renewable ones are required for reducing GHG emissions and for coping with the soaring in imported fossil energies prices. Importing natural energy resources as storable and transportable hydrogen transformed from wind power electricity may be preferable. If windmills of large quantity are constructed in the favored oversea regions, where steady and strong wind is blowing over wide area and the electricity cost becomes low.
Although it is difficult for hydrogen from overseas wind power generation to show economic efficiency in terms of calorific value compared to present fossil fuel prices, it was suggested that in the future, it would be more economical to stop using existing oil-fired thermal power stations and mix LNG with hydrogen at existing LNG power stations. As a means to reduce CO₂, it was also suggested that it would be more economical to mix LGN with hydrogen at existing LNG power stations if other power generation-related means exceed 7,000 yen/t-CO₂

抄録全体を表示