The full paper is open access. Those wires are going to thermocouples, not Peltier devices: https://www.nature.com/articles/s41467-018-03162-7/figures/2 https:/

The full paper is open access. Those wires are going to thermocouples, not Peltier devices: https://www.nature.com/articles/s41467-018-03162-7/figures/2 https://www.nature.com/articles/s41467-018-03162-7/figures/2 There is a heat sink, but it's not dissipating electrically produced heat. From the paper: During day-time water production, the enclosure is closed and the solar absorber side is covered with an optically transparent thermal insulator (OTTI aerogel). The MOF layer is heated by exposure to solar irradiance, causing water release (desorption). The desorbed water vapour diffuses from the MOF layer to the condenser due to a concentration gradient. Accumulation of vapour in the enclosure leads to saturation conditions and consequently, the condensation process occurs at ambient temperature. The heat of condensation is dissipated to the ambient by a heat sink.