Army invents tiny solar cells that are cheaper, stronger
The U.S. military is where many new technologies get their start. So much of what we now see as standard tech was once being invented in a military lab. Continuing that tradition, a team of Army scientists has created a new solar cell that could mark a major breakthrough.
The researchers have patented a new type of solar cell that is less expensive to manufacture, stronger and more robust than current solar cell technology. The main difference between this solar cell and those in existing solar panels is their size -- the new solar cell is approximately 1,000 times thinner.
The thin-film cell consists of layers of silver and gold between the semiconductor layers, but the combined thickness is still only a few hundred nanometers thick, compared to a piece of paper which is 100,000 nanometers thick.
The cell also overcomes some of the major problems with current solar tech like wear out or damage from high heat that comes from the absorption of great amounts of ultraviolet and infrared radiation that can't actually be turned into electricity due to a narrow band gap (the wavelength of light that can effectively be used to generate electricity). The addition of the silver and gold layers widens that bandgap meaning that the new solar cells can absorb and convert more of that UV and infrared radiation into electricity, which not only makes the technology more efficient, but also makes it much stronger and resilient.
The solar cells can also be tuned to reflect the excess radiation if needed.
The Army says that the geometry of the solar cells allows them to absorb the same rate of sunlight at any angle, which means that they don't need sophisticated sun tracking systems to generate the maximum amount of energy.
"Low-cost, compact, flexible and efficient solar cells are destined to impact all sorts of Department of Defense applications, as lightweight solar panels will eventually power all kinds of equipment, particularly in remote, inaccessible areas," said Dr. Michael Scalora, a research physicist at the U.S. Army Aviation and Missile Research, Development and Engineering Center.
The technology is just in the beginning stages, but the researchers see applications far beyond the military when it's ready.