Photon Number Hitting Solar Panel

A watt is a joule per second.

Photon number hitting solar panel.

Photon flux is an important concept in solar energy. We won t be pushed out of orbit as when we are pushed out to a larger orbit from the sun our angular velocity will be lowered increasing our acceleration back towards the sun. For more or less power multiply by the number of watts. Enough energy from the sun hits the earth every hour to power the planet for a year sunlight is made up of tiny packets of energy called photons these photons radiate out from the sun and about 93 million miles later they collide with a semiconductor on a solar panel here on earth.

In order to collect energy more efficiently solar panels should be angled to face as close to the sun as possible. If we are interested in knowing how much power we can generate from a solar panel we need to determine the amount of photons that are hitting the surface of our panels at any given time flux is just a technical term that denotes a quantity passing through a given surface area. Photons in sunlight hit the solar panel and are absorbed by semi conducting materials. That would suggest by dividing power by energy per photon that there would be about 3 x 10 18 photons per second.

The photon s energy is also absorbed by the electron. It all happens at the speed of light. As the next diagram shows panels like everything else are made up of atoms and atoms contain electrons. Looking at the big picture conservation of momentum implies that the momentum of the photon ultimately contributes to the momentum of earth.

The average visible light photon has about 3 3 x 10 19 joules of energy. Electrons negatively charged are knocked loose from their atoms as they are excited. When a photon hits an electron the photon is absorbed by the electron. A spectral response curve is shown below.

So tear down that solar panel or we ll be pushed out of orbit nb. The quantum efficiency gives the number of electrons output by the solar cell compared to the number of photons incident on the device while the spectral response is the ratio of the current generated by the solar cell to the power incident on the solar cell. Photovoltaics produce power when the angle at which the sun s rays hit the panel surface the angle of incidence is small or when light strikes the panel as close to perpendicular as possible.