The cost-competitiveness of concentrated solar power with thermal energy storage in power systems with high solar penetration levels

In this paper, we show that concentrated solar power (CSP) with thermal storage is an economically attractive technology to achieve high solar penetration levels. To this end, we utilize an alternative framework of net levelized cost of electricity (net-LCOE), which captures the projected curtailment rate, to economically compare PV with batteries to CSP in power systems with high levels of solar penetration. We also explore potential benefits enabled by hybrid PV-CSP configuration, which are unattainable by either technology independently. We show the existence of a turning point in power systems with 20%-30% solar penetration levels, after which it is cheaper to supply electricity by CSP with thermal storage by up to 16%. It is demonstrated that storing excess PV electricity in low-cost thermal storage is valuable, enabling CSP configuration with solar multiple as low as 0.5 to operate with a high capacity factor. Furthermore, we show that converting green hydrogen to electricity using CSP power block is cost-effective when seasonal storage is required, thus enabling deep decarbonization based on solar electricity. In these high solar penetration levels, using CSP resulted in a reduction of up to 65% in the net-LCOE. The results may enable researchers and policymakers to evaluate CSP with thermal energy storage as a cost-effective solution for achieving high penetration levels of solar electricity.