Saturday, May 11, 2013

Nanotechnology Can Make Solar Cells More Efficient

Renewable Energy



Gaining Efficiency via Nanotechnology: Current solar-panel technologies are not highly efficient in converting the sun’s energy into electricity for consumer use. As the article says: “The light glinting off the surface of this solar photovoltaic cell signifies lost efficiency. Scientists are looking to nanotechnology to boost solar power, including by reducing the amount of sunlight that silicon wastes through reflection.”
Photo Credit:  Martin Bond, Science Source
Source: NatGeo

An article, by Patrick J. Kiger, in National Geographic says that nanotechnology can soon make solar-cell technology both more efficient and less-expensive to produce than current technologies.

Kiger writes:
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. This contributes to the high cost of solar-generated electricity compared to power generated by conventional fossil-fuel-burning plants. By one comparative measure, the U.S. Energy Information Administration estimated the levelized cost of new solar PV as of 2012 was about 56 percent higher than the cost of generation from a conventional coal plant.
Nanotechnology may provide an answer to the efficiency problem, by tinkering with solar power cells at a fundamental level to boost their ability to convert sunlight into power, and by freeing the industry to use less expensive materials. If so, it would fulfill the predictions of some of nanotechnology's pioneers, like the late Nobel physicist Richard Smalley, who saw potential in nanoscale engineering to address the world's energy problems. (See related: "Nano's Big Future.") Scientists caution that there’s still a lot of work ahead to overcome technical challenges and make these inventions ready for prime time. For example, more research is needed on the environmental, health, and safety aspects of nano-materials, said the National Academy of Sciences in a 2012 report that looked broadly at nanotechnology, not at solar applications in particular. (See related pictures: "Seven Ingredients for Better Car Batteries.")
Again, we are now entering an exciting period in science and technology, where the promises of nanotechnology will soon be seen, likely within five to ten years. During the next few years, as solar panels become more efficient, capturing at least 30% of the sunlight, they will be more used as a source of energy, first perhaps as a back-up source, and then as a primary source of power.

It’s true that installation costs are currently high—the best being around $2.50 a watt—but this too will come down with increased consumer demand. And then consumers can get off the power grid, thus becoming energy independent, relying on nature’s supply from the sun. That day can’t come too soon.