Operational Parameter Database for Molten Salt Thermal Energy Storage Tank Modeling

Osorio, Julian [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000207619899); Saini, Prashant [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000176649939); Torres-Madronero, Jose [Pontifical Bolivarian University, Medellín (Colombia)]; Hankinson, Noah [National Laboratory of the Rockies (NLR), Golden, CO (United States)]; Gomez, Juan [Pontifical Bolivarian University, Medellín (Colombia)]; Nieto-Londono, Cesar [Pontifical Bolivarian University, Medellín (Colombia)]

doi:10.2172/3017381

DOE OSTI · 3017381

Operational Parameter Database for Molten Salt Thermal Energy Storage Tank Modeling

Osorio, Julian [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000207619899)·Saini, Prashant [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000176649939)·Torres-Madronero, Jose [Pontifical Bolivarian University, Medellín (Colombia)]·Hankinson, Noah [National Laboratory of the Rockies (NLR), Golden, CO (United States)]·Gomez, Juan [Pontifical Bolivarian University, Medellín (Colombia)]·Nieto-Londono, Cesar [Pontifical Bolivarian University, Medellín (Colombia)]

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Abstract

The second generation of concentrated solar power (CSP) plants is characterized by the use of a central receiver (either cavity or external), two molten nitrate salt tanks (60 wt.% NaNO 3 and 40 wt.% KNO 3 ), and a steam Rankine power-generation cycle connected through a primary heat exchanger. Molten salt thermal energy storage (TES) tanks have been widely deployed in commercial CSP plants worldwide and have been essential for increasing plant dispatchability and capacity factor, while also reducing the levelized cost of electricity (LCOE). These systems enable energy storage at the gigawatt-hour scale, typically providing 6 to 17 hours of storage duration. Despite being a commercial technology, the multiple failures observed after only a few months or years of operation in plants around the world demonstrate the technology's relative infancy and highlight the need for further research to improve its reliability. The National Laboratory of the Rockies (NLR), in collaboration with industry partners and academic and research institutions, has been leading multiple projects funded by the U.S. Department of Energy (DOE). These projects focus on addressing molten salt tank failures by improving tank design and welding fabrication practices, evaluating new alloys and weld fillers, and providing guidelines for tank commissioning and safe operation. In particular, this report presents modeling results on the effect of key tank operation parameters during 60 minutes of operation, including the mass flow rate and temperature of the salt inflow, tank salt inventory temperature, and inventory level for a representative molten salt tank design. These results form a database of tank operation behaviors that captures the effects of each specific parameter during charging, charging/discharging, and discharging processes.

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14 SOLAR ENERGY 25 ENERGY STORAGE mechanical stress molten salt thermal energy storage normal distortion parametric analysis plant operation tank floor welding fabrication temperature distribution

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Osorio, Julian [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000207619899), Saini, Prashant [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000176649939), Torres-Madronero, Jose [Pontifical Bolivarian University, Medellín (Colombia)], Hankinson, Noah [National Laboratory of the Rockies (NLR), Golden, CO (United States)], Gomez, Juan [Pontifical Bolivarian University, Medellín (Colombia)], Nieto-Londono, Cesar [Pontifical Bolivarian University, Medellín (Colombia)]. 2026-02-03. Operational Parameter Database for Molten Salt Thermal Energy Storage Tank Modeling. https://doi.org/10.2172/3017381

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