In an ideal world, affordable, sustainable power solutions with high output prevail. However, affordability and power efficiency are some of the main obstacles that must be overcome when it comes to renewable technologies. Fortunately, a new cell for solar panels may have proven that green is in fact “the new black” by significantly boosting sunlight absorption. Years ago, it may have been impossible to achieve these results, but now, thanks to this unconventional design, the odds have been beaten.
Conventional solar panels may become a thing of the past
The typical solar panel we all have come to know is made from silicon-based solar cells. While this technology has served its purpose of producing clean solar power, it may not ultimately be the best design for the job. According to a report by The World Economic Forum, silicon-based solar cells face production, performance, and application limitations, which include but are not limited to:
- Their production is highly resource-intensive
- Production is complex and expensive
- Production is energy-intensive
- Limited absorption
- Loss of efficiency
- Decreased output during high temperatures, which causes energy to be lost in heat
This is why researchers have been researching, developing, and testing new designs, with hopes of making solar power more affordable, sustainable, and efficient. While some have sought solutions beyond silicon, others have focused on improving the silicon design. Now, it seems the latter has paid off, as a more unconventional approach to silicon has beaten the odds.
Beating the odds with an unconventional cell
On February 26, 2014, inventor Bernard L. Sater filed for a patent for his creation, which could potentially reshape silicon-based solar panels. The key to his invention was introducing a reverse current limiting solution into a silicon vertical multi-junction (VMJ) solar cell. The partners to this project included:
- Photovolt, Inc.
- Department of Energy’s Inventions and Innovation Program
The cell consists of stacked layers of P-N junctions, with at least one layer stacked in a reversed proportion to the others. According to the fact sheet by Inventions and Innovation, this technology will be key to concentrated solar projects, such as the DLR’s 1.5 MW Solar Towers Jülich. While this type of power production may not have been common at the time of the patent application, it was already predicted that power production would increase to 600 MW by 2010.
The design itself uses crystalline silicon, which typically uses antireflective coatings to minimize reflection and enhance absorption. This coating gives it a unique green color, proving that green is the new black.
This cell proves that green is the new black
This design has additional benefits beyond large-scale power production. It is significantly more sustainable than conventional silicon designs, because
- Less silicon is used during production
- Photolithography processes are no longer needed
Furthermore, silicon VMJ cells generate higher voltages with lower current operation, and can operate at higher intensities with lower series resistance. This effectively increases cell efficiency while maintaining affordability. The one-wafer design can also operate in a variety of intensities and enables scalability. This opens doors to small-scale applications, such as dish power systems, portable power production, and lighting. This, in turn, increases access to clean, sustainable power, especially in rural regions.
There are, of course, some challenges to the technology that must not be overlooked, such as material limitations for multiple junctions and structure fragility. A ResearchGate report indicates that thermal issues prove to be another obstacle. But this is why further research and development are key to innovations, as they may lead to feasible solutions for these types of technologies. Now that more nations are investing in concentrated power, including the concentrated power plant with 12,000 mirrors in the Gobi Desert, now is as good a time as any to continue with this technology.
