A novel concentrating solar plant configuration with multiple solar fields and thermal energy storage to reduce energy production costs

Abstract

We propose and evaluate the use of a two-tank direct thermal energy storage system with a multi-field concentrating solar power plant. The plant includes parabolic trough collector and linear Fresnel reflector solar fields to generate electricity using a steam Rankine power cycle. Prior literature has assessed the performance of a multi-field configuration, but without thermal energy storage. Integrating thermal energy storage within the plant presents the potential to increase the plant's capacity factor while reducing the levelized cost of electricity (LCOE). A techno-economic analysis is performed considering the design and the off-design characteristics of the proposed configuration. A parametric analysis is also performed to minimize the levelized cost of electricity for the location of Jodhpur, India. The study reveals that there exists a minimum LCOE corresponding to each combination of the parabolic trough collector aperture area and hours of storage. Among all the combinations, the minimum LCOE is 0.283 $ kWh-1, corresponding to 34372 m2 of parabolic trough aperture area and 12 h of storage, which is 20 % less than that for a multi-field concentrating solar power plant without storage. The plant capacity factor is also increased to 70 %, thereby resulting in better dispatchability.

Keywords

• Design and off-design analysis
• Linear Fresnel reflector
• Parabolic trough collector
• Thermal energy storage
• Therminol VP – 1