A novel hybrid CSP-PV power plant based on brayton supercritical CO2 thermal machines

J.I. Linares, A. Martín-Colino, E.M. Arenas, M.J. Montes, A. Cantizano, J.R. Pérez-Domínguez

Applied Sciences Vol. 13, nº. 17, pp. 9532-1 - 9532-18

Summary:

A novel hybrid CSP-PV power plant is presented. Instead of the integration used in current hybrid power plants, where part of the PV production is charged into the thermal energy storage system through electrical resistors, the proposed system integrates both PV and thermal solar fields using a high-temperature heat pump. Both the heat pump and the heat engine are based on Brayton supercritical CO₂ thermodynamic cycles. Such integration allows for charging the molten salt storage as if a central tower receiver field supplied the thermal energy, whereas parabolic trough collectors are employed. Unlike conventional hybrid plants, where the storage of PV production leads to a decrease in power injected into the grid throughout the day, the power injected by the proposed system remains constant. The heat engine efficiency is 44.4%, and the COP is 2.32. The LCOE for a 50 MWe plant with up to 12 h of storage capacity is USD 171/MWh, which is lower than that of existing CSP power plants with comparable performance. Although the cost is higher compared with a PV plant with batteries, this hybrid system offers two significant advantages: it eliminates the consumption of critical raw materials in batteries, and all the electricity produced comes from a synchronous machine.

Spanish layman's summary:

Se propone una central híbrida CSP-PV, donde la fotovoltaica y el campo solar están integrados mediante una bomba de calor de alta temperatura. Los ciclos de potencia y bomba de calor son ciclos Brayton que usan CO2 supercrítico y están conectados por un almacenamiento térmico de sales fundidas.

English layman's summary:

A novel hybrid CSP-PV power plant is presented where PV and thermal solar fields are integrated by means of a high-temperature heat pump. Both cycles (heat pump and heat engine) are based on Brayton supercritical CO₂ thermodynamic cycles and are connected by a molten-salt thermal storage.

Keywords: Brayton supercritical CO2 power cycle; high-temperature heat pump; thermal energy storage; Carnot battery; CSP-PV hybrid power plant

JCR Impact Factor and WoS quartile: 2,700 - Q2 (2022)

DOI reference: https://doi.org/10.3390/app13179532

Published on paper: September 2023.

Published on-line: August 2023.

Citation:
J.I. Linares, A. Martín-Colino, E.M. Arenas, M.J. Montes, A. Cantizano, J.R. Pérez-Domínguez, A novel hybrid CSP-PV power plant based on brayton supercritical CO2 thermal machines. Applied Sciences. Vol. 13, nº. 17, pp. 9532-1 - 9532-18, September 2023. [Online: August 2023]