On 2017-09-06 09:06 AM, Alvin Starr via talk wrote: > > A client came to me asking about helping him setup an Etherium mining > server pool.
Hey, I know that there are some honest cryptocurrency types out there, but there are some definite shady ones around Toronto. One Etherium joker stole ~$500 of Raspberry Pis and accessories from my employer. Caveat consultor. I'm a (sometime) utility solar designer. The idea's interesting, but the implementation's tricky. > What if you glue a GPU with very little extra hardware to the back of a > solar panel. * Solar modules produce variable I-V output depending on sunlight and air temperature. You'll need to use some kind of inverter to stop your miners becoming puffs of expensive smoke in their first winter dawn. > Stick it out in the sun and let it calculate 8-10 hours a day. > Put a big heat sink on the GPU and it should be able to stay cool enough > just from air cooling * Solar modules run roughly 20°C hotter than ambient, often more. The huge project I worked on in Arizona quite frequently hit 45°C in the shade, so your GPU would be around 70°C under no load. * The dead air behind modules is *very* still. Passive cooling would likely melt. * You'd need to weatherproof your GPUs against water, dust and ice. Any crevices attract spiders and ants, and junction boxes in desert locations are a favoured haunt for scorpions and rattlesnakes. > Take a few thousand of these and set them out in a sunny place and you > would have a coin generator. * You'd need a small amount of ride-through battery, as a heavy cloud or shading on the wrong bit of the module can reduce your power output to close to zero. > Once the hardware is paid for then the operational cost would be close > to 0 but for some glass cleaner and rags. * Almost everywhere on the planet requires some kind of permit or environmental impact assessment. Even glass cleaner and rags need an MSDS and hazard management plan. * Some module types (thin film) are in perpetual danger of being classified as hazardous waste due to their cadmium content. * If you're far away from people, network is hard. * If you're in an isolated area, theft of solar equipment is a huge problem. * There's also something about solar modules that attract people with shotguns. It usually ends badly for your installation, unless there's a big fence. > They would need to be networked together but it does not have to be high > speed. > It could be a low power mesh to an edge that connects via something as > simple as cell phone data. * Solar modules, with all that wiring and semiconductor hanging about, make about the best radio signal attenuator I've ever seen. You only try to make a cell call or get a GPS fix under a solar array once. * The inverters you'll need can produce a fiendish amount of radio interference unless they're shielded in expensive enclosures. > Solar panels cost about $1/watt and there is no ongoing cost but power > here costs about $0.08-0.16/KWH. * Modules are way less than $1/W now. Racking will likely double the cost of your installation, though. * A utility-grade 330 Wp module is about 2 m² and weighs around 22 kg. At these latitudes, you'll get about 40 W average across the whole year. Since you're only proposing running through the day, you'd get more than that. Have a play on PVWatts <http://pvwatts.nrel.gov/> for hourly output. Choose a module like a Canadian Solar CS6U-330M for modelling: it's a solid Mono-Si module with decent efficiency. cheers, Stewart --- Talk Mailing List [email protected] https://gtalug.org/mailman/listinfo/talk
