Takanobu Kosugi

A CO2-capturing hybrid power-generation system with highly efficient use of solar thermal energy

Characteristics have been investigated for the proposed system. Saturated steam is produced at a relatively low temperature and is used as the working fluid for a methane-fired gas-turbine system. The solar thermal utilization efficiency is considerably higher than that for conventional solar thermal power plants in which superheated steam near 670 K is used. The proposed hybrid system recovers generated CO2 during combustion with oxygen. Characteristics of the system with 10,000 m2 collector area were estimated on the basis of a computer simulation model. The net generated power was 1.55 MW, the capacity factor 21.5% and the total exergetic efficiency 20.9% when the temperature of the saturated steam is 496 K. Based on the consumed fuel, the net thermal system efficiency is 63.7%.

Characteristics and economics assessment of power generation systems utilizing solar energy in various regions

Publisher Summary Under the restriction on CO 2 emissions, power generation systems utilizing solar energy (referred to as solar options) are expected to be introduced worldwide. Solar thermal system and solar photovoltaic system are well known as the solar option. However, these systems have difficulty to be introduced especially in the regions with lower solar radiation conditions from the economic point of view. As a kind of solar options, a CQ-capturing hybrid power generation system utilizing solar thermal energy (hybrid system) has been proposed in the chapter. The hybrid system emits no CO 2 in principle by using oxygen combustion method and has high net fuel-to-electricity efficiency of higher than 60 % on lower heat value basis. The system is thus expected to be applied for mitigating CO 2 emissions and for saving fossil-fuel instead of introducing high cost solar options.