Innovative integrated solar combined cycle: enhancing dispatchability with a partial recuperative gas turbine and supercritical CO2 bottoming cycle, coupled with an ORC

J.I. Linares, E.M. Arenas, A. Cantizano, M.J. Montes, A.J. Rovira, J. Porras, J.R. Pérez-Domínguez

Solar Energy Vol. 264, pp. 112075-1 - 112075-16

Summary:

Concentrating solar power is crucial in the future energy mix due to its ability to integrate thermal energy storage, thus providing dispatchability. One way to address the current high costs of this technology is by using higher temperatures, which can, however, lead to issues with heat transfer fluids and storage. A promising integrated solar combined cycle is here proposed to solve that current major issue. A partially recuperated gas turbine is coupled to a solar tower system using a Brayton supercritical CO₂ power cycle, which recovers heat at two temperature levels. An Organic Rankine Cycle is also used to exploit the low-temperature flue gases. The performance at the design point is assessed under different solar contributions. The modulation of the thermal duty in the gas turbine recuperator allows reaching a nearly constant power production in the plant (180 MWe): 56 % coming from the gas turbine, 39 % from the CO₂ power cycle, and 5 % from the ORC. The global efficiency achieved is 57.2 %. Carbon dioxide emissions range from 236 g CO₂/kWhe (86 g CH₄/kWhe are consumed) with the maximum solar contribution to 346 g CO₂/kWhe (126 g CH₄/kWh are consumed) with no solar contribution.

Spanish layman's summary:

Se propone un ciclo combinado integrado con una central solar de concentración, con ciclo Brayton de sCO2 y un ORC como ciclos de cola. Se han calculado los rendimientos en el punto nominal variando la contribución solar. La recuperación parcial en la turbina de gas permite una producción constante.

English layman's summary:

A novel combined cycle integrated with concentrating solar power is proposed with Brayton supercritical CO2 and Organic Rankine cycle as bottoming cycles. The design point performances under solar variations have been determined. Gas turbine partial recuperation enables constant output.

Keywords: Recuperative gas turbine; CSP; Combined cycle; supercritical CO2 power cycle

JCR Impact Factor and WoS quartile: 6,700 - Q2 (2022)

DOI reference: https://doi.org/10.1016/j.solener.2023.112075

Published on paper: November 2023.

Published on-line: October 2023.

Citation:
J.I. Linares, E.M. Arenas, A. Cantizano, M.J. Montes, A.J. Rovira, J. Porras, J.R. Pérez-Domínguez, Innovative integrated solar combined cycle: enhancing dispatchability with a partial recuperative gas turbine and supercritical CO2 bottoming cycle, coupled with an ORC. Solar Energy. Vol. 264, pp. 112075-1 - 112075-16, November 2023. [Online: October 2023]