As solar energy becomes a popular way to meet power needs, more efficient ways of harnessing the sun’s energy are being developed for solar photovoltaics (PVs). Solar cells capture energy in the sunlight and transform it into electricity for residential, business and industrial use. Because solar energy is clean, free, renewable and indigenous, it is a crucial component of major energy plans. Developing better technology to make high-quality solar energy affordable for consumers improves domestic energy security and increases competitiveness in global markets. Take a look at five cutting-edge photovoltaic technologies that are keeping sun power in the energy spotlight.
1. Crystalline Silicon Solar Cells A crystalline silicon cell has anti-reflective coating and a semiconductor with an n+ layer, a p-type layer, and a p+ layer sandwiched between two metal grids. Up to 25% efficient, they are the most popular PV type, occupying almost 90% of the global photovoltaic market. Research and development into crystalline silicon PV cells include improving semiconductor growth processes, reducing material volume and streamlining production methods. These technological innovations seek to make these solar cells more cost-effective for consumers.
2. Thin Film Solar Cells Thin film solar cells include amorphous silicone (a-Si), cadmium telluride (CdTe), copper indium gallium diselenide (CIGS) and copper zinc tin sulfide-selenide (CZTSSe) PV types. While inexpensive to produce, a-Si cells degrade rapidly in sunlight. Innovations seek to keep costs of a-Si PVs low while increasing product life through improved production techniques. CdTe cells are cheaper to produce than crystalline silicon PVs, but are less efficient. Advancements aim to increase performance by growing better quality crystals and improve manufacturing processes. CIGS research and development seeks to enhance the voltage and current of PVs by creating better window layers. Technology advancements for CZTSSe cells seek to strengthen structures and investigate options for incorporating other earth materials into PV designs.
3. Multijunction III-IV Solar Cells Multijunction III-IV cells have top cells, wide bandgap tunnel junctions, middle cells, tunnel junctions, buffer regions and nucleation sandwiched between contacts. With performance efficiencies of over 40%, they are very effective but are also very costly to produce. Technological development in this area focuses on creating better materials and production techniques. Efforts also seek to apply proven multijunction benefits to other types of cells.
4. Organic Solar Cells Because some of the materials used in photovoltaic manufacturing are finite, efforts are underway to incorporate abundant organic materials into solar cell production. Using abundant resources will help make PV cells more affordable to consumers. An organic photovoltaic cell has glass, transparent conductive oxide, a polymer mixture, an active layer, an acceptor, a donor, and an electrode. These types of cells are only about 10% efficient. Innovations include enhancing the organic absorber material and refining the metal contacts to make the cells last longer and be more efficient.
5. Dye-Sensitized Solar Cells (DSSCs) A dye-sensitized PV cell has transparent conductive oxide, a titanium dioxide (TiO2) blocking layer, TiO2, dye and hole conductors fitted between glass and an electrode. They have efficiencies above 10% and are easy to manufacture. Improvements in DSSCs include strengthening the durability of transport layers, increasing efficiencies of dyes and raising cost-competitiveness through the use of naturally prevalent materials.