Review of supercritical CO₂power cycles integrated with CSP

Abstract

Summary Increasing demand of electricity and severer concerns to environment call for green energy sources as well as efficient energy conversion systems. SCO2 power cycles integrated with concentrating solar power (CSP) are capable of enhancing the competitiveness of thermal solar electricity. This article makes a comprehensive review of supercritical CO2 power cycles integrated with CSP. A detailed comparison of four typical CSP technologies is conducted, and the cost challenge of currently CSP technologies is pointed out. The thermophysical properties of sCO2 and the corresponding two real gas effects are analyzed elaborately to express the features of sCO2 power cycles. An extensive review of sCO2 layouts relevant for CSP including 12 single layouts and 1 combined layout is implemented logically. Strengths and weaknesses of sCO2 power cycles over traditional steam‐Rankine cycle generally adopted in current CSP plants are concluded, followed by metal material degration summary in CSP relevant temperature sCO2 environment, which shows that the nickel‐based alloy is a proper structural material candidate for sCO2‐CSP integration. Thermodynamic analyses of sCO2 power cycles when integrated with CSP are divided into three level of which design‐point analysis and off‐design modeling are conducted and compared, more researches into the off‐design point analysis, dynamic modeling, especially the transient behavior are suggested. Economic analysis of the integrated system is concluded and presents a considerable levelized cost of electricity reduction of 15.6% to 67.7% compared to that of state of art CSP. Taking the thermodynamic and economic analysis into consideration, target designs of sCO2 power cycles for CSP are summarized in three aspects. Finally, current theoretical and experimental researches of sCO2 power cycles integrated with CSP for market penetration are introduced. The strengths, weaknesses, and potential solutions to the gaps of three potential pathways (molten salt pathway, particle pathway, and gas phase pathway) to realize the integration of sCO2 power cycles in the next CSP generation plants up to 700°C are reviewed. In general, the integration of sCO2 power cycles with CSP technologies exhibits promising expectations for facilitating the competitiveness of thermal solar electricity.

Thermodynamic and economic comparison of supercritical carbon dioxide coal‐fired power system with different improvements

“…9 Since the beginning of the 21st century, the SCO 2 power cycle has re-entered people's awareness with the development of the fourth generation nuclear reactor (Gen IV, core temperature 500-900 C). 6 This cycle can well match various types of heat sources and can be applied in many fields, such as nuclear power, [10][11][12] solar power, [13][14][15] thermal power, [16][17][18] and waste heat recovery. [19][20][21] At the same time, the SCO 2 cycle has high efficiency, compactness, and low noise.…”

Supercritical CO2 Binary Mixtures for Recompression Brayton s-CO2 Power Cycles Coupled to Solar Thermal Energy Plants

“…For the same reason, that ends as low as possible, as close to as possible. This will mean that the maximum amount of heat has been transferred from the hot flow (7)(8)(9) to the cold one (2)(3)(4)(5). This depends on how close the temperature profiles of the hot and cold flows can be brought together in the heat exchange, which is determined by the heat capacities of the two flows.…”

“…In this sense, supercritical carbon dioxide (s-CO2) Brayton power cycles have been identified as a suitable candidate for next-generation CSP (CSP Gen3) applications as they can operate at higher temperatures achieving increased thermodynamic performance [3,4]. Various configurations of the s-CO2 Brayton cycle are currently under study [4][5][6][7][8][9][10].…”

Novel energy station by natural fluid CO 2

“…2 Other than that, considering the metal degradation in the equipment used for concentrating solar power (CSP) at relevant temperatures of S-CO 2 environment, it has been shown that a nickel-based alloy is a proper structural material for S-CO 2 with CSP integration. 3 It will be better if we can configure the high-pressure expander with high P in and low T in , low-pressure expander with low P in and high T in , and low a T out air cooler. 4 A two-stage or multistage compression cycle (high coefficient of performance (COP), low power consumption, eg, DORIN) system with recuperator, high-efficiency heat exchanger, as well as optimal condensing and evaporating temperatures and exhaust pressure can increase the cooling capacity.…”