Review of thermal materials for CSP plants and lcoe evaluation for performance improvement using chilean strategic minerals: Lithium salts and copper foams

The improvement of solar thermal technologies in emerging economies like Chile is particularly attractive because the country is endowed with one of the most consistently high solar potentials, lithium and copper reserves. In recent years, growing interests for lithium based salts and copper foams in application of thermal technologies could change the landscape of Chile transforming its lithium reserves and copper availability into competitive energy produced in the region. This study reviews the technical advantages of using lithium based salts-applied as heat storage media and heat transfer fluid-and copper foam/Phase Change Materials (PCM) alternatives-applied as heat storage media-within tower and parabolic trough Concentrated Solar Power (CSP) plants, and presents a first systematic evaluation of the costs of these alternatives based on real plant data. The methodology applied is based on material data base compilation of price and technical properties, selection of CSP plant and estimation of amount of required material, and analysis of Levelized Cost of Electricity (LCOE). Results confirm that some lithium based salts are effective in reducing the amount of required material and costs for the Thermal Energy Storage (TES) systems for both plant cases, with savings of up to 68% and 4.14% in tons of salts and LCOE, respectively. Copper foam/PCM composites significantly increase thermal conductivity, decreasing the volume of the TES system, but costs of implementation are still higher than traditional options.