If you attended the 2022 Supercon, you might have heard the story about the SMD soldering challenge table nearly catching on fire. A magnifying lamp caught the sun just right and burned a neat trench into another lamp’s plastic base. While disaster was averted, [Jelle Seegers] does this on purpose using a huge 5-meter lens to smelt metal.
The Design Academy Eindhoven student is participating in Dutch Design Wee and built the machine which is able to manually track the sun to maximize the amount of solar energy applied to the metal.
According to [Seegers], the smelter is more sustainable and uses less energy than the normal procedure which he worked with during an internship.
The lens was also made manually by cutting into a sheet of polycarbonate with a custom-made machine. The operator has to turn the hand crank every 5 or 10 minutes to track the moving sun. The machine can heat to about 800 to 1,000C with an estimated 4 kilowatts of energy. It can melt 20 kg of zinc or 5 kg of aluminum.
This is probably more efficient than using a microwave. You can do a lot with direct solar energy instead of a laser.