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In this work, an exergoeconomic analysis is applied to the power cycle of a concentrated solar plant for its design improvement. A supercritical CO2 cycle connected with the exothermic reactor of a thermochemical storage unit is considered. The analysis is conducted with the goal of highlighting the advantages of exergoeconomic analysis while suggesting changes to both the design parameters and the system configuration. Starting from the plant configuration which guarantees the maximum efficiency, the exergoeconomic analysis is iteratively applied with the goal of reducing the unit cost of electricity. The analysis is conducted in a way that cost functions of the components can be substituted with the cost analysis of specific designs. This is a big advantage of this procedure, which is suitable for applications in which economic analysis requires a detailed knowledge of the system characteristics. The procedure is then validated comparing the results with those obtained through mathematical optimization.

The thermodynamic and thermoeconomic performances of a 21 MW geothermal power plant with air-cooled two level binary type organic Rankine cycle was numerically investigated based on its design and operating data. The investigated plant is the Sinem Geothermal Power Plant in Germencik, Aydin, Turkey. The paper provides a detailed comparison of the exergetic performance of this plant with other eight similar type of plant units, which make use of geothermal resources with similar specific exergies. Results indicate that the exergetic efficiency of the Sinem Geothermal Power Plant is the highest with 48.2% and the others vary between 9.6% and 42.7%. This result is mainly related to the exergy losses due to suppression of heat transfer in this plant, via low temperature brine reinjection, small temperature difference in the heat exchangers and high efficiencies of the individual components. First and second law efficiencies, as well as the exergy losses and improvement potentials of each component in the plant are also calculated. In air-cooled geothermal power plants, since ambient temperature is a critical parameter for the plant performance, both thermal and economic analysis of the plant is performed based on variation in ambient air temperature. Specifically, thermoeconomic analysis of the plant is evaluated to determine the exergoeconomic factor, the relative cost difference and the sum unit cost of the product (SUCP) of the plant. The effect of ambient temperature on the SUCP of the power plant, power generation, energy and exergy efficiencies are also examined in the present study. The results showed that; when the ambient temperature increases from 5 °C to 35 °C the reduction in power generation is 6.8 MW, energy efficiency decreases from 13.7% to 9.2% while exergy efficiency decreases from 54.9% to 36.7 and SUCP of the plant increases from nearly 230 $/GJ to 330 $/GJ. © 2019 Elsevier Ltd

Direct steam generation in parabolic-trough collectors is considered a promising option for reducing the cost of electricity produced in solar thermal power plants. Indeed, the use of water instead of thermal oil allows reaching high temperature levels and reducing plant complexity. Furthermore, the integration of thermal energy storage system and the hybridization of the plant with a biomass boiler permit further cost reduction. This paper focuses on the historical and technological development of the direct steam generation concept and the thermoeconomic analysis of a hybrid direct steam generation-biomass power plant equipped with a thermal energy storage system. The exergy balance and cost balance equations have been applied to each component of the plant in four different operating modes that take into account the intermittency of the solar source. Exergy results show that the solar field requires further development in order to reduce associated irreversibilities. Finally, it was found that the integration of a thermal energy storage system and hybridization with a biomass boiler reduce the final cost of electricity to 17.36c€/kW he.

Thermoeconomic analysis combines economic and thermodynamic analysis by applying the concept of cost, originally an economic property, to exergy. In this study, effects of different three working fluids as methanol, petroleum ether and distilled water on thermoeconomic analysis in the thermosyphon heat pipes which it heats the air is investigated. Under different air velocities, the energy and exergy efficiencies of the thermosyphon heat pipes are determined and compared in terms of thermoeconomic experimentally. Under all air velocities, while the highest energy and exergy performance are calculated for methanol, the lowest energy and exergy performance are calculated for petroleum ether. However, the thermoeconomic results of this study show that distilled water is more cost-effective than that of methanol and petroleum ether. © 2016 Elsevier Ltd. All rights reserved.

This paper aims at showing the capabilities of thermoeconomic analysis for solving cost assessments in district heating systems both at user and producer sides. In the near future it is expected that multiple producers are allowed to supply heat to the same district heating network, similarly to what happens in the case of the electric grid. Not only the amount of heat they may produce should be properly accounted, but also its quality, and also the pumping power that is requested to supply a unity of thermal energy to the end-users. Moreover, buildings equipped with low temperature heating system allow better use of the thermal energy vector, thus allowing larger efficiency of thermal plants. In the present work, the use of thermoeconomics for the analysis of these aspects is proposed. The approach allows one performing cost assessment in district heating, taking into account the effects of investment and operating costs and thermodynamic irreversibilities in the cost formation of heat from its production in the plants to its use in the buildings. Simple examples are analyzed in order to provide a quantitative evaluation of the various cost terms, depending on the operating conditions, topology and characteristics of the users/producers.