Flexible Solar Panels Move Indoors

Researchers at Virginia Tech are developing flexible solar cells that could replace window shades or even wallpaper, capturing and recycling the light from both the sun and indoor bulbs.

Using a low-temperature screen printing technique, the researchers are employing a titanium oxide paste to build palm-sized solar cells that can generate somewhere on the order of 75 milliwatts of power. At that rate, which the Virginia Tech says is nearly on par with the efficiency of rigid solar cells (10% as opposed to 13-15%), an 8.5”x11” flexible cell could recharge a cell phone (though how long that process would take isn’t mentioned).

One of the most compelling aspects of this new titanium-oxide solar cell is its ability to harvest a wide swath of the electromagnetic spectrum, lending it a number of applications that are out of bounds for traditional solar cells.

“The properties of the panels are such that there are really few limitations in terms of light source,” Said Shashank Priya, lead researcher on the project. “And the fact that we are dealing with an emerging technology, means we will be able to expand the utility of the panels as we go forward.”

While the efficiency of these titanium-oxide cells could likely be improved, their current ability and relatively low manufacturing cost makes them an ideal vehicle for testing new applications for solar power generation.

In fact, Priya’s lab is already working in conjunction with the U.S. Army’s Communications-Electronics Research, Development and Engineering Center to develop cells that could be embedded into military uniforms and other gear like backpacks. If these flexible cells could find their way into textiles, any person’s clothing, let alone the soldier on patrol, could become a remote charging station. And that idea alone might be able to dramatically shift the burden of power generation from fossil fuels to renewables.

Check out this story for another example of flexible solar cells with flexible applications.