Researchers at MIT have created the thinnest and lightest solar cells ever made, according to MIT News. The solar cells are so thin and light they can sit on a soap bubble without popping it. Their physical size means that they have the potential to be used in everything from paper to clothing to air- and spacecraft. In wearables, the solar cells are so light they would be virtually unnoticeable by the wearer.
The breakthrough was made by Vladimir Bulović, MIT’s associate dean for innovation and the Fariborz Maseeh Professor of Emerging Technology, research scientist Annie Wang, and doctoral student Joel Jean. The team worked for years to create a new process of engineering solar cells. In this case, Bulović and his team figured out how to combine three separate processes—making the solar cell, the substrate that supports it, and the environmental protective overcoating—into one.
The result is not only the thinnest and lightest solar cell ever made, but also one of the most energy efficient when you take its power-to-weight ratio into account. A typical silicon-based solar module produces "about 15 watts of power per kilogram of weight," MIT News reports. "The new cells have already demonstrated an output of 6 watts per gram — about 400 times higher."
Practical uses are myriad. Power-to-weight ratios are incredibly important in aeronautical and space endeavors, making these solar cells appealing for everything from high-altitude balloons delivering Internet connectivity in rural areas to spacecraft and satellites that require renewable energy.
The cells also have more down-to-earth applications. They could be applied to smartphones to draw power from the sun or even added to smart clothing or smart paper. "It could be so light that you don’t even know it’s there, on your shirt or on your notebook," Bulović told MIT News. "These cells could simply be an add-on to existing structures."
It’s important to note that right now the solar cells are just a working proof of concept, but the engineering and manufacturing process is sound, so the steps to commercialization are clearly laid out.
"How many miracles does it take to make it scalable?," Bulović told MIT News. "We think it’s a lot of hard work ahead, but likely no miracles needed."