Earlier quoted context omitted.
There were cholera epidemics in the 19th century, until we realized we shouldn't drink contaminated water. In cities such as London, this required major infrastructure investments. We're just realizing we shouldn't breathe contaminated air, and we're just realizing that we need to make infrastructure investments. CO2 is a good proxy for infectious disease transmission risk. We breathe out CO2 as we spread pathogens.…
> if our new building will have DC wiring for LED lights, rather than a cheap, inefficient transformer in every bulb, This blows my mind too. I expect it's coming, though: the cables would be cheaper, and if there's one driver of change in construction, it's cost. Another question is, would it be a straight improvement? I think transformers are typically very efficient, and I could imagine the losses from running a l…
You could make it to ~30ft on existing wiring as long as you kept draw under 5A. That’s ~60W and enough to power all of 5 pretty anemic 12V bulbs.
If you actually need something like a 60ft run from your transformer and 15A to play with, you’re going to be looking more towards something like 6AWG. If you want to keep under 3% voltage drop you’d be looking towards 2AWG.
14AWG 2-wire is something like $0.35/ft. 6AWG 2-wire is like $0.75/ft. 2AWG 2-wire is coming up on $3/ft.
There’s a reason we use AC for power distribution rather than DC.