Question by : How the sun can produce heating directly in solar heating?
and how the sun can prouduce electricty usin solar cells?
Best answer:
Answer by oldprof
Radiant energy is electro magnetic energy, it’s part of the EM spectrum just like visible light is. So it passes directly from the Sun, through space, and into collecting devices sitting on a roof top, for example.
These devices are typically long lengths of pipe that absorb the radiant energy and heat up some sort of liquid in those pipes. Ordinary water can do the job, but other liquids with high heat capacities can also do it. The hotter liquid on the roof pushes that liquid towards the cooler liquid inside the house or whatever. So pumps are not needed to get the liquid to circulate. It’s a very cost effective way to heat a place. Of course the draw back is that the heating stops when the Sun goes behind clouds or night falls.
Electricity is produced when photons from the Sun strike some photoelectric material, like silicon, and knock bonded electrons off the material’s atoms to become so-called free electrons. These free electrons flow from the roof, where the solar cells are, to a distribution system that is at a lower negative charge than the charge on the roof. That flow of electrons is the current and represents the electric power than can be consumed or sold back to the power company.
Add your own answer in the comments!