Modeling and performance assessment of Concentrated Photovoltaic Thermal solar tower systems

Concentrated Photovoltaic Thermal (CPVT) solar towers combine high efficiency Photovoltaic (PV) and Concentrated Solar Thermal (CST) technologies to simultaneously generate electricity and recover heat from the cooling system. Integration of thermal energy storage (TES) provides flexibility, reducing curtailment and dependence on solar availability. Literature on CPVT towers lacks integrated receiver and plant models with techno-economic analyses, and their thermo-electric performance under solar tower-specific conditions is poorly characterized. This work develops a comprehensive CPVT solar tower model accounting for environmental factors such as soiling and flux non-uniformities from heliostat field-generated maps. A thermo-electrical receiver model is coupled with TES and power block to calculate annual energy yield, levelized and actual cost of electricity (LCOE, ACOE). The model is demonstrated through a case study in Australia. Receiver connections are optimized to minimize mismatches, resulting in a residual efficiency loss of 5.7%. Performance is minimally affected by sun position, with across- and intra-day efficiency variations of 0.6–2.2%. The plant is analyzed under two dispatch scenarios: continuous, producing 11.08 GW h yr -1 with LCOE of 83.09 $/MWh; and grid-constrained, reducing yield by 30% and resulting in ACOE of 119.74 $/MWh. The CPVT plant demonstrates economic competitiveness with Concentrated Solar Power (CSP), yet remains less competitive than PV, while exhibiting greater operational flexibility and lower curtailment. Overall, the developed model establishes a techno-economic framework for evaluating CPVT solar towers within the broader solar energy landscape, demonstrating avenues for competitive dispatchability and further performance improvement.