No sunlight required to turn ambient heat into power: Sealed hydrovoltaic cell can be used in desert and dark environments

https://www.scmp.com/news/china/science/article/3288316/chinese-teams-cell-turns-ambient-heat-power-no-sunlight-required

"drawing heat from surrounds, continuously creates water vapor within hermetically sealed container for electricity generation... wind/ humidity resistance enables use in harsh environments... internal circulation hydrovoltaic effect... low cost, easy accessibility, stable electricity output for 160 hours with negligible water consumption... sealed cell made from carbon black and tissue paper... hydrovoltaic electricity generation which captures energy from the interaction of water with surfaces"