TECHNOLOGY FOCUS - ELECTRONICS - Preferred Module: In the module, the polymer comprises a polyolefin grafted with an anhydride, an acid, or an acrylate, a polyethylene wax, a poly(ethylene-co-maleic anhydride), a poly(ethylene-co-methacrylic acid) or a salt, a polyisobutylene, or a polyurethane made from a polyol and a diisocyanate. The polymer comprises a poly(ethylene-co-methacrylic acid) or a salt, or a polyurethane made from a toluene diisocyanate and a polyol selected from a polyether polyol, a polyester polyol, a neopentyl polyol, and a cyclopentane polyol. The polymer has a glass transition temperature of at most 120 degrees C, preferably 80 degrees C. The polymer is 70-100% by weight of the buffer layer. The buffer layer further comprises a filler, where the filler comprises a nanoclay, and where the nanoclay comprises montmorillonite, kaolinite, llite, or chlorite. The filler is 0-30% by weight of the buffer layer, where the buffer layer covers substantially the entire area between the first electrode and the adhesion layer. The module comprises a second photovoltaic cell separated from the first photovoltaic cell by an interconnection area for electrically connecting the first and second photovoltaic cells, and the buffer layer covers the interconnection area; a set of photovoltaic cells; each photovoltaic cell has first and second electrodes, and a photoactive layer between the first and second electrodes; the buffer layer is between the first electrode in each photovoltaic cell and the adhesion layer; and the buffer covers substantially the entire area between the first electrode in each photovoltaic cell and the adhesion layer. The buffer layer has a moisture vapor transmission rate of at most 0.01 g/m2/day, and where the buffer layer has a thickness of 25-250 microns. The adhesive comprises an epoxy resin. The barrier layer comprises at least two polymer layers and at least two ceramic layers between the at least two polymer layers. The barrier layer comprises a metal foil. Alternatively, the module comprises: a first photovoltaic cell comprising first and second electrodes, and a photoactive layer between the first and second electrodes; a barrier layer supported by the first photovoltaic cell, the first electrode being between the barrier layer and the photoactive layer; and a buffer layer comprising a polymer that comprises a polyolefin grafted with an anhydride, an acid, or an acrylate, the buffer layer being between the first electrode and the barrier layer; where the module does not include an additional adhesive layer between the buffer layer and the barrier layer. The polyolefin comprises a homopolymer or copolymer. The polyolefin comprises a polyethylene, a polypropylene, a poly(ethylene-co-vinyl acetate), or a poly(ethylene-co-acrylate). The buffer layer comprises a low-density polyethylene grafted with an anhydride, a linear low-density polyethylene grafted with an anhydride, a high density polyethylene grafted with an anhydride, a polypropylene grafted with an anhydride, a poly(ethylene-co-acrylate) grated with an anhydride or an acid, and a poly(ethylene-co-vinyl acetate) grafted with an anhydride, an acid, or an acrylate.