Table 1.

OSTE efficiency (%) and characteristics of potential integrations of solar power generation methods and energy storage techniques based on 4.8 h of solar availability and 24 h of continuous power supply at a constant rate

Energy storage method and OSTE efficiencies, %
Solar power systemSTE, %Li-ion (90)Na/S (75)Zn/Br (65)CSC (59)PH (81)TES (90)Hydricity
Current technologies
 Solar thermal
  Air*17.015.613.411.910.914.3
  Molten salt*22.020.217.415.414.118.520.2
  Stirling engine31.228.724.621.820.126.3
 PV
  Silicon–crystalline27.625.321.819.317.723.2
  Single-junction29.126.723.020.318.724.5
  Four-junction44.741.135.331.228.737.6
Proposed processes
 Solar thermal
  SWP-1 (750 K)30.827.924.021.219.525.6
  SWP-1 (1,600 K)42.739.233.729.827.435.934.3
  SWP-3 (1,600 K)44.540.935.231.128.637.5
  • The batteries used are as follows: Li-ion, Na/S, Zn/Br (20); CSC, carbon storage cycle (19); PH, pumped hydroelectric storage (16); SWP-n, solar water power cycle with n reheating stages; SWH2P, solar water hydrogen power; TES, thermal energy storage (16). The numbers in parentheses are roundtrip storage efficiencies in percentages for the respective energy storage method.

  • * Central tower receiver thermal power plant with specified working fluid.