Potential of Supercritical Carbon Dioxide Power Cycles to Reduce the Levelised Cost of Electricity of Contemporary Concentrated Solar Power Plants

Abstract

This paper provides an assessment of the expected Levelised Cost of Electricity enabled by Concentrated Solar Power plants based on Supercritical Carbon Dioxide (sCO 2 ) technology. A global approach is presented, relying on previous results by the authors in order to ascertain whether these innovative power cycles have the potential to achieve the very low costs of electricity reported in the literature. From a previous thermodynamic analysis of sCO 2 cycles, three layouts are shortlisted and their installation costs are compared prior to assessing the corresponding cost of electricity. Amongst them, the Transcritical layout is then discarded due to the virtually impossible implementation in locations with high ambient temperature. The remaining layouts, Allam and Partial Cooling are then modelled and their Levelised Cost of Electricity is calculated for a number of cases and two different locations in North America. Each case is characterised by a different dispatch control scheme and set of financial assumptions. A Concentrated Solar Power plant based on steam turbine technology is also added to the assessment for the sake of comparison. The analysis yields electricity costs varying in the range from 8 to over 11 ¢/kWh, which is near but definitely not below the 6 ¢/kWh target set forth by different administrations. Nevertheless, in spite of the results, a review of the conservative assumptions adopted in the analysis suggests that attaining costs substantially lower than this is very likely. In other words, the results presented in this paper can be taken as an upper limit of the economic performance attainable by Supercritical Carbon Dioxide in Concentrated Solar Power applications.

Numerical Simulation of Supercritical Carbon Dioxide Dry Gas Seal

“…The dry gas seal (DGS) is the recommended sealing solution for the Brayton cycle system utilizing Supercritical carbon dioxide (S-CO2) as the working medium [1,2]. This is due to its reliability, costeffectiveness, safety, and minimal leakage in comparison to other seal types [3].…”

Multi-objective optimization of a small scale SCO2 turbine rotor system with a shaft cooler

“…Conventional steam Rankine cycle operate at a temperature of less than 550 °C [1][2][3], based on a trade-off between material selection, safety and reliability of circulatory mediator and rotor speed of the turbomachinery accounting also for bearings and seals induced restrictions of operating temperatures and pressures [4][5][6]. In recent years, reliability combined with the high thermal efficiencies related advantages has led to an increasing attention to supercritical carbon dioxide (SCO 2 ) energy conversion system [7].…”

Integrated Aerodynamic and Structural Blade Shape Optimization of Axial Turbines Operating With Supercritical Carbon Dioxide Blended With Dopants

“…Introducing new working fluids like supercritical carbon dioxide (sCO2) and sCO2 blended with dopants in power generation cycles has a high potential to increase the thermal efficiency and decrease the associated capital and operational costs [1,2]. Numerous studies have focused on analysing the performance of pure sCO2 power plants as well as sCO2 mixtures [3] where the results have proven that introducing blends to the cycle potentially increase the efficiency and ensure feasible operation of transcritical power cycles especially in hot weather.…”