Simultaneous design and operational optimization of hybrid CSP-PV plants

The dispatchability of renewable power plants and the role of energy storage are gaining relevance leading to the development of hybrid CSP-PV plants. This work investigates the optimal design of highly integrated CSP-PV power plants. The integration occurs not only at grid level (synergic operation as a virtual power plant), but also through the introduction of electric heaters, placed in parallel to the solar field: the excess PV electricity is converted into heat by electric heaters and stored in the CSP hot storage tank. The whole system design is optimized devising an ad hoc Mixed Integer Linear Program (MILP) which co-optimizes design and operational variables with accurate linearization of all nonlinear effects. Compared to the respective stand-alone technologies (only CSP or PV plus battery), the results show that the hybrid solutions can achieve similar or better dispatchability levels at a lower cost of electricity (LCOE reduction between −30% and −50%).