Those can or downspout collectors are rad, thx Kevin. Not sure if they would be useful enough in Winter, probably 50/50- we get lots of sun at times but also suffer some gnarly inversions in the valley every couple of years where there is no sun at all for an extended period of time. I'm way into the idea of doing it with beer cans.
It would be sick to rig a big one of these up for year round use where it feeds the dryer itself with warm air, reducing the energy needed to heat the dryer and then use a heat exchanger on the outtake of the dryer to warm the shop as needed.
Any super big shops want to chime in? I'm curious what you do with 10k sf +. I imagine a lot of spot heating where it's needed.