Lossless hybridization between photovoltaic and thermoelectric devices

Abstract

The optimal hybridization of photovoltaic (PV) and thermoelectric (TE) devices has long been considered ideal for the efficient harnessing solar energy. Our hybrid approach uses full spectrum solar energy via lossless coupling between PV and TE devices while collecting waste energy from thermalization and transmission losses from PV devices. Achieving lossless coupling makes the power output from the hybrid device equal to the sum of the maximum power outputs produced separately from individual PV and TE devices. TE devices need to have low internal resistances enough to convey photo-generated currents without sacrificing the PV fill factor. Concomitantly, a large number of p-n legs are preferred to drive a high Seebeck voltage in TE. Our simple method of attaching a TE device to a PV device has greatly improved the conversion efficiency and power output of the PV device (~30% at a 15°C temperature gradient across a TE device).

Suitability of Electrical Coupling in Solar Cell Thermoelectric Hybridization

“…This is in line with what was reported in previous electrical hybridization studies [9,16,[20][21][22][23]. The behavior shown in Figure 2 also indicates that there is a minimum (and therefore a minimum ∆T) capable of compensating the decrease of the PV filling factor, giving thus = 1.…”

“…Thus, for the electrically hybridized HTEPV device, the power output reads: P el htepv = P pv + P teg − P loss (4) As shown by Park et al [21], for a given R i,teg , a V teg exists (and thus a temperature difference at the TEG sides) that allows the HTEPV device to work in an electrical lossless condition (i.e., for which P loss is negligible). However, it must be pointed out that either for lower or higher values of V teg , this lossless condition is no longer fulfilled.…”

“…In principle, , may take any value. In addition, the IV curves were fitted using the following equation [21], which is the single diode equation for the solar cell accounting for the addition of the TEG in the same circuit:…”

“…Specifically, Fisac et al [20] and Park et al [21] analyzed silicon solar cells. Fisac et al reported experimental and theoretical results of the hybridization of a silicon panel, showing a small increase of the overall efficiency when operating at 55 • C. Unfortunately, the lack of details on the experimental procedure and on the thermoelectric generators used in their work makes it difficult to generalize their results.…”

A One‐Structure‐Based Multieffects Coupled Nanogenerator for Simultaneously Scavenging Thermal, Solar, and Mechanical Energies

“…To date, binary/multivariate hybridization among piezoelectric, triboelectric, pyroelectric, thermoelectric (TE), electromagnetic, and photovoltaic energy harvesters, either in series or in parallels, has been widely performed to realize self‐powered operation of electronics with high power consumption 6, 7, 8, 9, 10, 11, 12, 13. Despite significant advances in enhancement of overall power output, complex device structure limits the interaction of various effects since the generated electricity is separately exported through distinct electrodes.…”