Two months ago I posted the news of a start up that found a way to increase the conversion rate of solar light into electricity by stacking different materials and thus covering more wavelength of light. Now I run onto a news of researchers at the mIT that have found an almost ideal way to harvest all wavelengths of solar light and convert them into heat (that in turns can be converted into electricity).
They have managed to create a two dimensional metallic dielectric photonics crystal that can be manufactured in such a way to embed tiny cavities that are hit by the various wavelengths. The material is covered by an antireflective layer that basically makes sure that all incoming light reaches the cavities. The shape (depth) of the cavities is such that photons are captured and their energy is converted into heat.
The material is able to sustain very high temperatures: in an experiment it has been able to "work" at about 1,000° Celsius for a period of 24 hours without any sign of degrade. Also very important, the material can be produced at low cost.
As we can see material science is progressing continuously bringing us more and more options to leverage on sun light for our energy needs.
Capturing as much solar "energy" as possibile is clearly good but it is not enough. We need to find ways to accumulate this energy and then distribute it when needed, since sunlight is not usually in synch with our energy need, time-wise...