Stefano Barberis

Thermoeconomic Optimization of CSP Hybrid Power Plants With Thermal Storage

This paper investigates the integration of Concentrating Solar Power technology in Combined Cycles for power production. Starting from a state of the art of CSP plants, the paper investigates alternative plant configurations, assessed and compared with a through-life thermoeconomic analysis. Plant layouts include thermal storage to manage the load demand of the plant throughout the day, considering both variable solar input and variable power demand. Focus is on the impact of thermal storage devices on optimal layouts.The hybrid combined CSP plants are analyzed using original software tools, WTEMP for the design point analysis and WECoMP for the time-dependent thermoeconomic optimization, to take into proper account the time-dependent nature of both the electrical load demand and the hour-by-hour irradiation during the year.The analysis shows that combining CSP technology with existing combined cycles a significant reduction of fuel consumption and greenhouse gas emissions is obtained, with an optimal solar share factor of about 20%, providing the grid with fully dispatchable power generation.Copyright

Dynamic Analysis of Concentrated Solar Hybridised Gas Turbine

In this work the dynamic behaviour and the control strategy of a 12MWe size gas turbine hybridised with concentrated solar heat source has been investigated. Hybridised gas turbine cycles are attractive because of their high efficiency, potentially equal to combined cycle efficiency, and because of their dispatchable power capability. An existing gas turbine model has been modified into a hybrid layout to incorporate high temperature heat from a concentrated solar field, through a high pressure air-cooled receiver. The system does not involve any hot air valve and includes a ceramic thermal storage. The plant dynamic model was developed using the original TRANSEO simulation tool developed at the University of Genoa. Initially, plant steady-state performance is analysed, identifying potential issues. Then, the different dynamic operations (storage charging, discharging and bypass) are simulated, showing the feasibility of the control strategy proposed. Eventually, design recommendations are drawn to improve the flexibility and the time response of such kind of plants.© 2014 ASME

Thermoeconomic Analysis of CSP Air-Steam Mixed Cycles

This paper investigates the integration of Concentrating Solar Power technology in air-steam Mixed Cycles for power production. Starting from a state of the art of CSP plants and the undergoing research in hybridization of Gas Turbine plants, the paper investigates alternative plant configurations particularly regarding the integration of CSP technology with mixed cycles, assessed and compared with a through-life thermo-economic analysis.Solar heat collected by on the market CSP mirrors at moderate temperatures (300°C–500°C) can be employed to increase conventional steam-injection gas turbine power plants performances. Solar concentrating collectors for current steam solar power plants can be used for such an application can be simpler and less expensive than collectors supposed to be used for hybrid GT CSP Plants which need high temperature systems (collectors and receivers).The solar hybridization of mixed cycles could be a good opportunity to combine gas turbine technology and CSP systems thus augmenting efficiency and achieving power dispatchability, but avoiding dedicated combustion chambers for hybrid CSP purposes (one of the big technologic problems to combine CSP and Gas Turbine technology). Moreover, the availability of commercial steam injected gas turbines at intermediate power range (10–100MW) allows the realization of such hybrid mixed CSP power plants in their typical size, avoiding the need for very large solar fields and reducing the technological risk as well as the time to market.Focus is on the design of the plant that was made analyzing different factor like solar share factor, water consumption and reintegration and LCOE. A comparison of this innovative hybrid CSP-STIG plant with traditional STIG, Integrated Solar Combined Cycles (ISCC) and a traditional Combined Cycle was made. The mixed cycles CSP plants are analyzed using the original software WTEMP for the design point analysis, whose library was updated with dedicated modules.The analysis shows that combining CSP technology with existing mixed cycles lets cost-competitive plant configurations with a relatively short time to market.Copyright