From my Quora.com feed, in which I’ve volunteered to answer questions related to science, a young reader asks: Can we trap light and use it as an energy source?

Ovis writes: Almost all sources of energy on Earth is in some way or the other linked to sunlight: fossil fuels are the result of sunlight that was trapped over a period of millions of years.  Then we have PV, wind, biomass, and hydro.  The only exceptions are nuclear and geothermal power.

I respond: Good answer, Ovis.  To the list of exceptions I would add tidal hydro and, to a certain extent, ocean current hydro.  Here’s an infographic on all the forms of energy available to us here on Earth.