Upending a theory of physics maintained for over a century, researchers at the University of Michigan have discovered that magnetic fields coming from light waves are 100 times stronger than previously believed, creating new possibilities for harvesting solar power.
According to PhysOrg, this discovery came about when researchers ran a light source through a non-electric material:
Light has electric and magnetic components. Until now, scientists thought the effects of the magnetic field were so weak that they could be ignored. What Rand and his colleagues found is that at the right intensity, when light is travelling through a material that does not conduct electricity, the light field can generate magnetic effects that are 100 million times stronger than previously expected. Under these circumstances, the magnetic effects develop strength equivalent to a strong electric effect.
With current technology, the light has to be focused at an intensity of 10 million watts per centimetre squared, which is far stronger than natural intensity of the sun. However they’re working with materials that will allow less intense light sources to produce energy (they’re currently working with lasers).
The researchers believe that this breakthrough could lead to the development of an “optical battery”, that doesn’t use semiconductors, and doesn’t need to absorb the light (which gives off heat during the process). Meaning this technology could be cheaper and more efficient. They believe that with a bit more research and better materials, 10 per cent efficiency can be attained, which is the current percentage for commercial-grade panels. [PhysOrg]
Photo credit: Flickr/Pixor