Within the next decade, solar panels may look vastly different from what we see today. They could resemble energy technologies like wind and storage more closely.
Solar energy has an essential role to play in our transition towards a sustainable energy future. It can work hand-in-hand with electric vehicles, integrate with new clean fuels, and more for maximum impact on our environment.
1. Thin-Film Solar Cells
Solar panels made with thin-film technology are currently the most promising and rapidly developing type of solar panel. Their thinness and flexibility make them ideal for use in a range of applications.
Thin-film solar cells are created by depositing a thin layer of semiconductor (such as amorphous silicon, cadmium telluride or copper indium gallium diselenide) onto an organic substrate like glass, plastic or metal using chemical vapour deposition processes.
These materials are strong light absorbers and can be applied on large substrates. Furthermore, they offer lower costs than traditional crystalline silicon solar cells due to their lower material costs.
Thin-film solar cells are becoming more competitive and will soon surpass pure silicon-based technologies; however, they still have a long way to go before reaching this point. Nonetheless, thin-film solar cells may find lucrative niches in small scale off-grid products and solar on roofs and facades.
2. Organic Solar Cells
Organic solar cells (also referred to as OPVs) are an exciting new type of photovoltaic device that has recently gained interest among researchers. They consist of thin, flexible layers composed of carbon-based compounds.
When light strikes these devices, an electron is released from organic molecules and an exciton (a combination of an electron and hole) is formed. This produces an electric current which can be used to charge batteries.
Organic cells have a much lower efficiency than silicon technology, currently around 18% in laboratory conditions. To improve their efficacy, materials used as donor and acceptor layers must have excellent extinction coefficients, high stability and an intact film structure.
Recent research has demonstrated how this could be overcome by inhibiting the recombination of an undesirable state in organic molecules that results in their loss of electrical currents. This means future organic solar cells could achieve efficiency levels close to those achieved with silicon.
3. Perovskite Solar Cells
Perovskite solar cells offer a cost-effective and energy efficient alternative to silicon, the material currently used in solar panels. Plus, these cells can be easily made using simple additive deposition techniques for cost efficiency.
Before these technologies can become widely adopted, researchers must first solve several challenges. Most notably, they need to determine how to maintain these materials’ stability when exposed to extreme temperature variations in real-world applications.
In one such study, researchers were able to create a lead halide perovskite that maintains conversion efficiency even when temperatures fluctuate between -60 degC and +80 degC. This is significant for solar applications since much energy is lost when temperatures drop.
Perovskites have long intrigued researchers with their potential as low-cost, high-efficiency solar cells. Unfortunately, they’ve encountered several obstacles along the way – including a relatively short lifespan and the fact that they deteriorate rapidly when exposed to moisture, necessitating them to be encapsulated in order to prevent leaching out of the cell.
4. Nanocrystalline Solar Cells
Solar cells utilize light to generate electricity. They are composed of silicon and can be manufactured in either crystalline or thin-film forms.
Crystalline silicon cells utilizing p-n junctions are used, while thin film versions employ semiconductors such as cadmium tin oxide (CdTe) or copper indium gallium diselenide (CIGS). While not as efficient as regular crystalline cells, these thin film options can be mass produced and offer low cost solar power production at relatively low costs.
Recent research by scientists at Penn State University revealed that adding nanoparticles to perovskite cells could increase their efficiency by 1%. The particles act like millions of tiny mirrors, reflecting light as it passes through the device.