Hydrovoltaic electricity generation induced by living leaf transpiration

Hydrovoltaic electricity generation, being demonstrated through various forms of water movement, holds great promise for advancing green energy technologies. However, the natural transpiration of plant leaves, as the largest water flux on land accumulating immense latent energy, has rarely been directly harvested. Here we present a living leaf transpiration generator using a lotus leaf, enabling direct harvest of latent energy via leaf transpiration. The leaf transpiration generator demonstrated sustained all-day electricity generation, featuring an open-circuit voltage of 0.25 V and a short-circuit current of 50 nA, which was effectively amplified in series or parallel connections. Partial least squares path modelling analysis indicated that improved electricity generation was attributed to enhanced transpiration rate, stomatal conductivity and temperature, while increased relative humidity had a counteractive effect. This study not only uncovers the unprecedented hydrovoltaic effect of leaf transpiration but also provides a fresh perspective for advancing green energy technologies through the widespread phenomenon of leaf transpiration. This study presents the hydrovoltaic electricity generation induced by living leaf transpiration. It emphasizes the hydrovoltaic effect in various plant species, showcasing a new, untapped source of green energy from natural transpiration processes.