Uninterrupted Self‐Generation Thermoelectric Power Device Based on the Radiative Cooling Emitter and Solar Selective Absorber

Abstract

Self‐generation power devices based on the radiative cooling effect have intense potential applications in the energy conversion field. A selective solar absorber is introduced into thermoelectric generator (TEG) devices based on radiative cooling emitters (RCEs). The self‐generation device can work continuously for 24 h, and the output power is greatly enhanced. The RCE is prepared as a polydimethylsiloxane–Al structure by a simple squeegee method. The solar selective absorber (SSA) of the W–Si–O laminated film is prepared by the magnetron sputtering method. Its working temperature can reach as high as 85 °C under AM1.5 sunlight. The calculation results prove that the selective solar absorber can achieve 1.55 times the net heating power of an ideal blackbody at the same working temperature of 85 °C. The assembled self‐generation power device achieves output powers of 695.1 and 5.23 mW m−2 on clear days and nights, respectively, as well as an output power of 7.64 mW m−2 even in the cloudy daytime. The result of theoretical calculation proves that the addition of SSA can greatly increase the temperature difference and the average working temperature, which improves the efficiency of the TEG and the output power of the device.

Cellulose‐Based Radiative Cooling and Solar Heating Powers Ionic Thermoelectrics

“…[ 37 ] At ambient conditions (15 to 40 °C, 20%<RH<70%), the Seebeck coefficient (thermal voltage/temperature difference) of this electrolyte is between 6 to 13 mV K −1 , [ 37 ] which is much higher than that of electronic thermoelectric materials (see Figure S8, Supporting Information). Different from the vertical structure of thermoelectric devices that have been reported, [ 28,29 ] the lateral structure further allows water dynamics in the electrolyte films, which has been reported to contribute to the thermal voltage in addition to ionic thermodiffusion. [ 37 ]…”

“…[25][26][27] Solar heating and radiative cooling were also recently combined to generate temperature differences in thermoelectric generators during both daytime and nighttime. [28,29] However, previous research was limited to combining radiative cooling with commercial thermoelectrics based on traditional inorganic materials, which poses limitations of cost, performance and sustainability. In turn, research on ionic thermoelectrics has experienced rapid growth recently owing to not only environmentally friendly material compositions but also superior Seebeck coefficients and correspondingly much larger thermovoltages than provided by electronic thermoelectric systems.…”

An Emerging Energy Technology: Self‐Uninterrupted Electricity Power Harvesting from the Sun and Cold Space

“…As discussed above, the output performance ( P max and η) of TEG depend on its intrinsic properties and operating temperature ( Figure 2 g,h). [ 32 ] So far, the energy conversion efficiency has gradually increased from 3–6% of the first generation thermoelectric system to 12–15%. [ 8 ] What is more, the output power of TEG can vary from several microwatts to several hundred watts according to its volume (or mass).…”

Enabling Highly Enhanced Solar Thermoelectric Generator Efficiency by a CuCrMnCoAlN-Based Spectrally Selective Absorber

“…Moreover, the STEGs driven by different solar absorber coatings were compared with similar reports in terms of their optical properties and TEG performance. 22,42,46 For the STEG system, the performance of the temperature difference and voltage depend on the synergy of SSA and TEG. As shown in Table 1, benefitting from the high spectral selectivity, the STEG driven by our CuCrMnCoAlN-based SSA shows a higher temperature difference, reflecting the superiority of our work.…”