Fig. 2: The water-saving capacity of SAWH technologies in greenhouses.
a Schematic illustration of various HPPs35,36,37,38,93,94,95,96,97. PDA@PP-Cl polydopamin @ PAAS−PNIPAA-HCL, POG hygroscopic photothermal organogel, PGF porous sodium polyacrylate/graphene framework, SMCA solar-driven and moisture-indicating cellulose aerogel, ILCA Loofah grafted calcium alginate sorbent with ink. Reproduced with permission36. Copyright 2019, Wiley. Reproduced with permission37. Copyright, AAAS. Reproduced with permission38. Copyright 2022, Royal Society of Chemistry. Reproduced with permission93. Copyright 2022, American Chemical Society. Reproduced with permission94. Copyright 2020, Wiley. Reproduced with permission95. Copyright 2020, Wiley. Reproduced with permission96. Copyright 2021, Royal Society of Chemistry. Reproduced with permission97. Copyright 2021, Elsevier. b Schematic representation of a greenhouse with SAWH covers. c Schematic depiction of crops with SAWH hoods. d Temperature and humidity fluctuations in a greenhouse during a typical sunny day in Singapore, where the average RH is ~90%. e Comparison of water production at 90% RH for different types of HPPs35,36,37,38,93,94,95,96,97. f Daily harvested water mass for SAWH covers and hoods. Relevant raw data are taken from ref. 30. Needed water: additional water needed to meet the needs of plant daily growth. Harvested water: water collected from SAWH cover or hood. The dashed lines in the figure represent the needed water amounts at different levels.
