Sunlight provides vast amounts of energy spread out across the Earth’s surface. Scientists are experimenting with enormous mirrors that follow the Sun and reflect its light to produce concentrated sunlight. Powerful enough to ignite timber, melt steel and even melt rock, this concentrated sunlight might be the future for power generation.
image/source: Madoka Chiba
We have all seen, metal being, melted under sunlight, but this video shows, a natural ,stone being ,meltedCommonly seen, using a small magnifying glass, You get a V-shape curve of light if off angle to the sun instead of a spot which spreads the heat over a larger area.
With a large fresnel lens you can already see that a lot of light is scattered around the main spot.So by using this it makes it quick to set up and reduces the light scatter as much a possible.He directed the heat from the furnace at a piece of rock and effectively liquified it.
In the video, the rock bursts and liquifies quite quickly after being put under the concentrated beam of light. It starts smoking almost immediately, shooting off sparks and eventually turning into something like a puddle beneath the light beam.