#video about #energy from bifacial #solar #photovoltaic panels mounted vertically in Ohio, showing production curves throughout the day, and how some reflectors on the ground change them. He says Sirius brand bifacial panels, from a company in Texas, are 45¢ a watt, assembled; cloudy days have about a third as much energy as sunny days, but affect the vertical panels less; and overall the vertical panels only produce 79% of the conventionally mounted south-facing bifacial panels. It looks like he’s using a roll of shiny wrapping paper for his ground reflector (he says it’s a large roll of mylar) and stretched it over wooden boxes, supported on pallets 20° from horizontal. Reflector results plot at 12’01". They’re still not as good as conventional south-facing panels (8% better than vertical bifacial panels without reflectors, but only 83% as good as bifacial south-facing panels) but maybe different reflector designs could improve this. The midday dip was only down to 150 watts per panel instead of the previous 100. Lots and lots of time-wasting talking-head footage, even if he is standing in front of a solar panel.
#video #toread about #3D-printing #optics components (not lenses, prisms, and mirrors tho) #Breaking-Taps
#Breaking-Taps #video #toread about DIY laser #photolithography
#video about #optics microlens arrays as a “key to our sci-fi future”. Nanometer-sized pillars on a silicon wafer; company is Metalenz. Video (by "Freethink") is pretty clueless and gives no real information about #metamaterials except that they can do polarization imaging. Lots of talking-head filler. #Plonk
#Breaking-Taps #video about looking at #precision flat surfaces with atomic force #microscopy. His new gauge block has 12 nanometer RMS surface roughness with a total range of almost ±50nm over the 10μm square field of his AFM. A first-surface mirror is 3nm RMS with 36nm range. A λ/20 fused silica mirror blank (λ = 632.8nm) is 2nm RMS, 39nm range. A cheap glass microscope slide is 1.9nm RMS, 62nm range, mostly due to a few big peaks. A silicon wafer is 1.6nm RMS, 17nm range. And a piece of mica (!!!) is 530 picometers RMS, 8nm range.
#video #toread about #precision lapping three flat cast-iron discs using the Whitworth method.
#video about scraping the #Gingery lathe bed flat with #precision hand scraping after roughing it in with an angle grinder flap disc
#video about the 20GW 283km² (or 39000km²?) #wind #energy farm in Gansu, #China, the Jiuquan Wind Power Base, with 7000 windmills, for which they’re building #HVDC transmission lines. As usual with Matt Ferrell #Undecided videos, it’s 100% talking heads and stock footage, therefore a waste of time. Although seeing the wind farm was cool.
how electrons can be conducted by metals, in terms of #quantum #physics
#video #toread about #Argentina tourism at Temaikén in Russian
flattering #video by former employees on what it's like to work for #elmu