Most drone flights are of limited duration, but that could change with the adoption of photovoltaic batteries, according to TechXplore.com. Researchers at UC Berkeley report that new advancements in photovoltaic efficiency could allow the lightweight power source to keep a drone aloft for days at a time.
Professor of electrical engineering and computer science, Eli Yablonovitch, explains, “Thermophotovoltaics are compact and extremely efficient for a wide range of applications, from those that require as little as 100 watts, [like] a lightweight unmanned aerial vehicle, to 100 megawatts, [which could provide] electricity for 36,000 homes. In comparison, a 100-megawatt combined cycle power plant is massive.”
Applying principles that allow the cell to emit, rather than absorb, excess photons is the key to the enhanced efficiency. Scientists added a mirrored back to the cells and added a graphite ribbon to heat those cells. “What the mirror does is create a dense infrared luminescent photon gas within the solar cell, a phenomenon that adds voltage,” Yablonovitch told TechXplore.com.
Already the old threshold of 23 percent efficiency has been increased to 29 percent. Scientists are hopeful that with additional research, efficiency levels can be bumped up as high as 50 percent.
August 27, 2019