The Stirling cycle engine post reminded me of these solar furnaces. Under the right conditions they can produce a great deal of heat without much in the way of complicated machinery. A few generate enough heat to melt steel, and smaller versions can be used for cooking or heating water.
I put together a solar filter to cap on the end of my telescope for the 2017 solar eclipse. Was worried I was going to burn a hole through my face when I looked in lol. Focused light is no joke.
I'm always struck by how much heat you can concentrate with a relatively small number of mirrors. Same with prisms and lenses. One of my buddies has a neat half-circle burned in to his kitchen table because he left a crystal orb there on a sunny day.
There are a bunch of neat Frensel Lens death rays on youtube
Stereotactic radiosurgery (AKA Gamma Knife) takes advantage of the same property of light to focus intensely. In this case it is exploited to be able to kill brain tumors without having to cut through healthy tissue, since the intensity is so low for each individual beam, but very high where all the (dozens of) beams intersect. Always thought that was a cool use of science. Though in this case, there’s really no such thing as focusing x-rays/gamma radiation. It’s done through collimating of radioactive sources.
There’s a reason if you ever buy a crystal ball they tell you “don’t leave it uncovered it will burn your house down”
also, sauron can look through it when its uncovered
Putting solar panels in desert areas is sometimes talked about, with the downside that it is difficult to transmit that energy to where people live. I wonder if an alternate way to harness all that free energy would be to set up solar metal foundries in the desert? Smelting metal is very energy intensive, and so maybe building the foundries at the source of the energy makes more sense.
I don't know how feasible that really is, given that you still need workers to do the smelting part, and workers tend to not want to live in the desert, not to mention that the desert seems to actively be trying to kill your workforce. I seem to remember that Morocco and Algeria had big plans for a massive solar panel project in their respective parts of the Sahara, but I haven't heard about those projects in a while, so they might have gotten shelved in favour of something a little less ambitious.
https://www.nrel.gov/csp/facility-hfsf.html
Here's one used for research in the US
If you're ever in Uzbekistan you can visit the largest solar furnace in the world
https://en.wikipedia.org/wiki/Solar_furnace_of_Uzbekistan
Here's one of the original large furnaces in France
https://en.wikipedia.org/wiki/Mont-Louis_Solar_Furnace
Archimedes
makes a heat ray
Mythbusters:
🤓 Umm ackshully it took 10 minutes and required no clouds, so this myth is busted
This can only be done with a wide range of wavelengths.
Just yellow can't melt steel beams.
I made a little solar furnace in elementary school. Fun things
