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This paper provides the theoretical calculation results of thermodynamic and transport properties of CO2, CO2–O2 mixture, CO2–H2 mixture under thermal equilibrium condition at temperatures of 300 to 30,000 K and at pressures of 0.1 to 10 MPa. The gas CO2 is one of the candidates for the environmentally benign arc-quenching medium in a circuit breaker. Furthermore, the effect of additional gases O2 and H2 on the thermodynamic and transport properties of CO2 was also investigated in this paper. The hydrogen atom included CO2 is similar to the polymer ablated vapor in switching devices. First, equilibrium compositions of CO2, CO2–O2 mixture, CO2–H2 mixture were calculated through the Gibbs free energy minimization method. Second, thermodynamic properties were computed using the calculated composition. Finally, transport properties were calculated by the first-order approximation of Chapman– Enskog method using the collision integrals between species. Inclusion of H2 increases the electrical conductivity of CO2 in the range 3000 to 6000 K because CHO molecules produced in this temperature range emit more electrons due to the lower ionization potential of CHO. It also increases the thermal conductivity of CO2 especially due to dissociation reactions of H2 around 3900 K and ionization of H around 15,000 K. These properties provided here can be used for CO2 thermal plasma simulation. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(4): 18–29, 2008; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/eej.20467 [ABSTRACT FROM AUTHOR]

Abatement of CO2 emission is one of the most important issues in the 21st century regarding preservation of the earth environment. This paper addresses a utility operations planning problem for distributed energy management systems (DEMSs), where we are to obtain optimal plans that minimize both costs and CO2 emissions. A DEMS consists of multiple entities that seek their own economic profits. In this paper, we give a mathematical formulation of the utility operations planning problem for each entity, and propose an energy trading market, which utlizes a multi-attribute auction protocol in order to deal with both a price and a CO2 emission rate. Experimental results show that collaboration among entities through the market provides a more profitable plan for each entity and abatement of CO2 emission is also achieved. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(4): 54–63, 2008; Published online in Wiley InterScience (www.interscience.wiley. com). DOI 10.1002/eej.20418 [ABSTRACT FROM AUTHOR]

This paper considers the effectiveness of the service business approach for reducing CO2 emissions. 'HDRIVE' is a service business using inverters to reduce the energy consumption of motor drive. The business model of this service is changed to find new opportunities of CO2 emission reduction by combining various factors such as financial services or long-term service contracts. Risk analysis of this business model is very important for providing stable services to users over the long term. The HDRIVE business model is found to be suitable for this objective. This service can be applied effectively to industries such as chemicals or steel, where CO2 emissions are very large, and has the possibility of creating new business considering CDM or trading CO2 emission rights. The effectiveness of this approach is demonstrated through several examples in real business. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 179(3): 40-48, 2012; Published online in Wiley Online Library (). DOI 10.1002/eej.21242 [ABSTRACT FROM AUTHOR]

This paper proposes a novel method based on real options theory for economic evaluation of the replacement of an old coal-fired thermal power plant (COAL) with a coal-fired thermal power plant that includes a CCS (carbon dioxide capture and storage) unit. We calculate the real option value (ROV) of CCS as the value of an American call option with dividend, treating the increased carbon cost of COAL due to the delay of replacement as opportunity cost. The appropriate construction time of a CCS unit is evaluated by binominal decision tree analysis for option exercise. We calculate the change of project ROV and the appropriate construction time according to the difference in carbon emission benchmarks and the variation of the maintenance cost of COAL. The effect of power station lifetime is also analyzed. We conclude that flexibility in the timing of decision making increases the value of a project. We also found that CCS is an economically justifiable technology option under forthcoming restrictions on carbon emissions. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(3): 9-17, 2011; Published online in Wiley Online Library (). DOI 10.1002/eej.21065 [ABSTRACT FROM AUTHOR]

Possible designs for a self-sufficient residential binary solar energy include a side-by-side system, a PVT hybrid system, and a side-by-side PVT hybrid system. We designed and performed an annual performance simulation of three systems: PV with flat plate collector (PV/FPC), photovoltaic-thermal hybrid (PVT), and PV with photovoltaic-thermal hybrid (PV/PVT) including an electrical auxiliary heat pump. In this paper, the solar energy fraction (SEF) or auxiliary energy fraction (AUX) is used as a figure of merit for system evaluation. These indices are shown to be affected by the COP (coefficient of performance) of AUX and by the ratio of the DHW (domestic hot water) load to the annual synthetic load. The best results were achieved by the side-by-side PV/PVT hybrid system. Using PVT with PV leads to an improvement of the SEF or AEF compared with the PVT system alone. Glazing is found to be indispensable for the PV/PVT system with an AUX COP of 1, but is unnecessary for a PV/PVT system with a higher COP. © 2001 Scripta Technica, Electr Eng Jpn, 137(1): 28–35, 2001 [ABSTRACT FROM AUTHOR]

This Paper presents an efficient computational algorithm for selecting the optimal generation mix considering CO 2 emission. To demonstrate the effectiveness and feasibility of the proposed method, a fundamental study of the evaluation of the optimal generation mix for controlling CO2 emissions is indicated, Futhermore, by using parametric analysis which considers load characteristics as parameters, a general trend for the optimal generation mix which is affected by controlling CO2 can be derived. The proposed method is based on an optimization method know as simulated. In the method, solution in a generation mix problems are equivalent to states of physical system, and the cost of a solution is equivalent to a state. The proposed method can easily accommodate not only CO2 emission but also many practical constrains of generation expansion planning, such interger solutions of unit capacities, condition of existing units, and so on. Case studies various annual load patterns (combinations of annual factors and the shapes of annual load duration curve) are presented and discussed. Consequently, a general trent for selecting generation technologies that should be added to a power system is derived, i.e., a useful guideline for studying generation expansion planning under controlling CO2 emission can be provided. [ABSTRACT FROM AUTHOR]

This paper describes the characteristics and construction of a coal-gas-burned high efficiency power plant which emits no carbon dioxide (CO2) into the atmosphere. In a plant, CO2 gas and superheated steam are used as the main and the secondary working fluids, respectively, of a closed dual fluid regenerative gas turbine power plant. Since coal gas composed of CO, H2, CO2 and CH4 is burned in a combustor using oxygen, the exhaust gas let into a condenser includes only CO2 and H2O. Hence, CO2 gas can be easily separated at the condenser outlet from condensate. In the plant, the combustion gas is first used to generate power by driving a turbine. High-temperature turbine exhaust gas is next utilized at a regenerator to heat the main working fluid of CO2 gas flowing into the combustor, and then is utilized at a waste heat boiler to produce the superheated steam injected into the combustor. It is estimated that the power can be generated with gross thermal efficiency of 54.4 percent, and that the power generating efficiency is 46.7 percent. Generating efficiency is calculated by subtracting the power required for producing the high-pressure oxygen used for combustion from the generator output. It is shown that the estimated efficiency is higher by 18.1 percent than that of a conventional boiler steam turbine power generating plant into which a process for removing and recovering CO2 from the stack gas by utilizing alkanolamine-based solvent is integrated. [ABSTRACT FROM AUTHOR]

SUMMARY This paper investigates the impact of an extensive introduction of electric vehicles ( EV) and plug-in hybrid vehicles ( PHEV) into the global energy system by 2050. The significant growth of automobile ownership in emerging countries is likely to increase world oil demand and the associated carbon dioxide emissions. In order to address these energy, security, and environmental concerns, the deployment of clean energy vehicles, such as EV and PHEV, is expected to play a crucial role due to their high fuel efficiency. Consequently, we develop both a global energy system model and a world vehicle penetration model, which can explicitly analyze the impact of EV introduction into the seasonal daily electric load curve, with consideration of the specific electricity charging profile through 2050. The simulation results confirm that EV deployment contributes to energy conservation, because oil demand reduction outstrips the growth in electricity demand and the associated fuel input into the power generation mix. Concerning carbon dioxide abatement, the magnitude of the impact relies on the carbon intensity of the power generation mix. If the intensity is low enough to guarantee a carbon mitigation effect due to EV fuel saving, emissions reduction is well assured. It should be noted, however, that in regions with high carbon intensity in the power generation mix, carbon emissions per mileage of EVs is almost equivalent to that of efficient gasoline vehicles such as hybrid vehicles, and the figure for PHEV is slightly higher than for hybrid vehicles. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(4): 20-36, 2014; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22373 [ABSTRACT FROM AUTHOR]