We have to make a homemade solar water heater.the rules:1no moving parts2no commercial products3can't spend more than 10 dollarswe have to heat 100mL of water in 25 minutesany ideas?
Thank you everyone for your helpful answers.
Very fine metal mesh in grounded Faraday cage - mesh has to be finer than wave lengthSolid metal will also do it - lead is rather too soft and heavy for most situations.
What i've seen done for a similar project (Solar still) is taking a large mixing bowl (polished stainless steel or lined with aluminum foil), a beaker (glass works best) or jar, Paint the inside of the jar black for better resultsAlso, you can use a beer bottle (brown) and that works pretty wellyou have to have a dark color to absorb the heatA beer bottle is 355 MLSuspend the bottle over the center of the bowlMuch like a satelite dish, the bowl will concentrate the incomming solar energy to the centerWhere you're using light, you'll want to point the bowl in the direction of the sun for best results.
