Solar gets bigger by getting smaller
Photovoltaic cells have doubled and quadrupled in efficiency since they were first introduced to the world in 1954. Even so, solar panels haven’t yet been able to compete with fossil fuels. That could all change by looking to nanotechnology. (Q)[A]lternative energy researchers think that something really small—nanotechnology, the engineering of structures a fraction of the width of a human hair—could give a gigantic boost to solar energy.
"Advances in nanotechnology will lead to higher efficiencies and lower costs, and these can and likely will be significant," explains Matt Beard, a senior scientist for the U.S. Department of Energy's National Renewable Energy Laboratory (NREL). "In fact, nanotechnology is already having dramatic effects on the science of solar cells." (&Q)
Creating more efficient solar panels is an important step in renewable energy since the Sun produces an immense amount of energy that we’re currently only able to harness a fraction of.
(Q)The power output of the Sun that reaches the Earth could provide as much as 10,000 times more energy than the combined output of all the commercial power plants on the planet, according to the National Academy of Engineering. The problem is how to harvest that energy. Today’s commercial solar cells, usually fashioned from silicon, are still relatively expensive to produce (even though prices have come down), and they generally manage to capture only 10 to 20 percent of the sunlight that strikes them.(&Q)
This is where nanotechnology comes in. There are many different ways for nanotech to help solar cells be more efficient, all of which work at the most fundamental levels of the cells.
(Q)[L]ate last year, NREL scientists announced a breakthrough in the use of nanotechnology to reduce the amount of light that silicon cells reflect. It involves using a liquid process to put billions of nano-sized holes in each square inch of a solar cell’s surface. Since the holes are smaller than the light wavelengths hitting them, the light is absorbed rather than reflected. The new material, which is called "black silicon ," is nearly 20 percent more efficient than existing silicon cell designs.
[A] team of Princeton University researchers, led by electrical engineer Stephen Chou, has been able to nearly triple the efficiency of solar cells by devising a nanostructured "sandwich" of metal and plastic... It consists of a thin strip of plastic sandwiched between a top layer made from an incredibly fine metal mesh and a bottom layer of the metal film used in conventional solar cells.
[I]n a January 2013 article published in Scientific Reports, Northwestern University mechanical engineering professor Wei Chen and graduate student Cheng Sun introduced a method that might be superior to human brainstorming. Using a mathematical search algorithm based on natural biological evolution, they took dozens of design elements and then "mated" them over a series of 20 generations, in a process that mimicked the evolutionary principles of crossover and genetic mutation.(&Q)
This is only a selection of the changes that nanotechnology can make to improve the efficiency of solar panels. As these new techniques for improving solar cells are implemented, there will be increased interest in solar energy production, and DC microgrid technology--like the DC power technology available from Nextek Power Systems--to make solar energy production and consumption even more efficient.
To read more about the nanotechnology being developed for solar panels, visit National Geographic.