The three storage materials mostly used in CSP plant in the United States and other developed and developing countries include molten salt, steam-based thermal storage and ammonia-based storage system. While the thermal capacity of molten salt has the potential to facilitate more storage capacity with substantially diminished storage volume and costs, hence enabling efficient and cheap heat storage as well as the use of efficient supercritical steam cycles, steam-based thermal storage is known to eliminate the need for a heat exchanger between the primary heat transfer fluid and the steam cycle. However, steam-based thermal storage is more challenging to use as it is substantially constrained by the use of steam and the high cost of pressure vessels. Ammonia-based thermo-chemical storage systems are particularly effective in CSP plants using the Big Dish technology, though they are still in their developmental phases

The three storage materials mostly used in CSP plant in the United States and other developed and developing countries include molten salt, steam-based thermal storage and ammonia-based storage system. While the thermal capacity of molten salt has the potential to facilitate more storage capacity with substantially diminished storage volume and costs, hence enabling efficient and cheap heat storage as well as the use of efficient supercritical steam cycles, steam-based thermal storage is known to eliminate the need for a heat exchanger between the primary heat transfer fluid and the steam cycle. However, steam-based thermal storage is more challenging to use as it is substantially constrained by the use of steam and the high cost of pressure vessels. Ammonia-based thermo-chemical storage systems are particularly effective in CSP plants using the Big Dish technology, though they are still in their developmental phases (IEA-ETSAP and IRENA, 2013).