High-performance floating thermoelectric generator for all-day power supply

Thermoelectric generators (TEGs) offer notable benefits in harnessing diverse low-grade waste heat from the environment. However, the uninterrupted capture of these energy resources still remains a huge challenge. Herein, we have developed a temperature-adaptive floating thermoelectric generator (TAFTEG) by integrating a temperature-adaptive absorber/emitter (TAA/E) to synergistically exploit renewable energy from the sun, outer space, and the water bodies by leveraging diurnal spectrally selective absorption and nocturnal radiative cooling. The W_xV_1-xO₂-based TAA/E demonstrates remarkably solar absorption of ∼96 % and a superior switching ability of dynamic thermal radiation modulation from the low emission of ∼45 % to high emission of ∼81 %. Assembled with 8 pairs of Bi₂Te₃-based TEG legs, the TAFTEG enables a stable temperature difference of 34°C under indoor solar irradiation (1 kW m⁻²), yielding a peak power output of ∼1.0 mW cm⁻², and continuous all-day power supply under both clear and overcast conditions. This strategy paves a new avenue toward the round-the-clock power supply from ambient environments.