Metal Power

Renewable energy is not simply "clean" or "green" or "carbon free." Its real character is like the "potato-powered" light bulb you may have constructed in elementary school. The potato was part of the equation, but what actually powered the light bulb was the transfer of ions between zinc and copper nails. If your teacher called it "potato power", that was misleading.

Solar, wind, hydro, geothermal... all of these "renewable" energies are made available using materials, such as batteries and capacitors, that do the work of managing, transporting, storing, and imparting energy for final use. So there are an array of non-renewable materials at the heart of renewable energy, mostly metals. And no, we can't use potatoes instead.