A system for distilling water is disclosed. The system comprises a heat source, and a plurality of open-cycle adsorption stages, each stage comprising a plurality of beds and an evaporator and a condenser between a first bed and a second bed, wherein each bed comprises at least two vapor valves, a plurality of hollow tubes, a plurality of channels adapted for transferring water vapor to and from at least one of the condenser or the evaporator, a thermally conductive water vapor adsorbent, and wherein each vapor valve connects a bed to either the condenser or the evaporator.

An embodiment includes a method of texturing a semiconductor substrate, a semiconductor substrate manufactured using the method, and a solar cell including the semiconductor substrate, the method including: forming metal nanoparticles on a semiconductor substrate, primarily etching the semiconductor substrate, removing the metal nanoparticles, and secondarily etching the primarily etched semiconductor substrate to form nanostructures.

A back contact structure of a solar cell, includes: a silicon substrate, the silicon substrate including a back surface including a plurality of recesses disposed at intervals; a plurality of first conductive regions and a plurality of second conductive regions disposed alternately in the plurality of recesses, where each first conductive region includes a first dielectric layer and a first doped region which are disposed successively in the plurality of recesses, and each second conductive region includes a second doped region; a second dielectric layer disposed between the plurality of first conductive regions and the plurality of second conductive regions; and a conductive layer disposed on the plurality of first conductive regions and the plurality of second conductive regions.

A back contact structure includes: a silicon substrate including a back surface including a plurality of recesses disposed at intervals; a plurality of first conductive regions and a plurality of second conductive regions disposed alternately on the back surface of the silicon substrate; a second dielectric layer disposed between the plurality of first conductive regions and the plurality of second conductive regions; and a conductive layer disposed on the plurality of first conductive regions and the plurality of second conductive regions. One of the plurality of first conductive regions and the plurality of second conductive regions is disposed inside the plurality of recesses, respectively, and the other one is disposed outside the plurality of recesses; each first conductive region includes a first dielectric layer and a first doped region which are disposed successively, and each second conductive region includes a second doped region.

A back contact structure includes: a silicon substrate including a back surface including a plurality of recesses disposed at intervals; a first dielectric layer disposed on the back surface of the silicon substrate; a plurality of first doped regions disposed on the first dielectric layer and disposed inside the plurality of recesses; a plurality of second doped regions disposed on the first dielectric layer and disposed outside the plurality of recesses; a second dielectric layer disposed between the first doped regions and the second doped regions; and a conductive layer disposed on the first plurality of doped regions and the plurality of second doped regions.

A multijunction solar cell including interconnected first and second discrete semiconductor regions disposed adjacent and parallel to each other including first top solar subcell, second (and possibly third) lattice matched middle solar subcells; a graded interlayer adjacent to the last middle solar subcell; and a bottom solar subcell adjacent to said graded interlayer being lattice mismatched with respect to the last middle solar subcell; wherein an opening is provided from the bottom side of the semiconductor body to one or more of the solar subcells so as to allow a discrete electrical connector to be made extending in free space and to electrically connect contact pads on one or more of the solar subcells.

The present invention relates to an optoelectronic device comprising a substrate having a first and a second substantially planar face, a series of grooves in the first substantially planar face, and a first and a second electrical conductor on the second substantially planar face; wherein a first face of the first electrical conductor and a first face of the second electrical conductor are reflective.

A perovskite-silicon tandem cell capable of absorbing solar radiation with energy lower than that of 1.12 eV, i.e., the bandgap of crystalline silicon—corresponding to the wavelength of 1100 nm. Ho.sup.3+ can absorb photons of wavelength range 1120 to 1190 nm, Tm.sup.3+, 1190 to 1260 nm, and Er.sup.3+, 1145 to 1580 nm, but up-conversion can be achieved using Ho.sup.3+, Tm.sup.3+, and Er.sup.3+-doped metal oxide, such as ZrO.sub.2, in perovskite-silicon tandem solar cells. Doped metal oxides, such as ZrO.sub.2 can also work as selective contacts. Such perovskite-silicon tandem structures can achieve over 30% solar energy conversion efficiency.

Disclosed are a reflector for a bifacial solar module and a bifacial photovoltaic system including the same, wherein the reflector includes a reflecting panel configured to reflect sunrays toward back surfaces of a first bifacial solar module and a second bifacial solar module which are located higher than the ground, a mobile cart configured to support the reflecting panel and be movable below and between the first bifacial solar module and the second bifacial solar module, and a control portion configured to control a position of the mobile cart to maximize power generation amounts of the first bifacial solar module and the second bifacial solar module.

Disclosed are a solar cell and a solar cell module comprising same, the solar cell comprising: a solar cell structure having one or more hollows passing therethrough in the height direction, and a plurality of light-concentrating parts disposed in each of the one or more hollows.