No. If you run low voltage DC that matches what devices need (5V or 12V, typically), your wiring is staggeringly huge. Not only do you need the fat wire to ca

No. If you run low voltage DC that matches what devices need (5V or 12V, typically), your wiring is staggeringly huge. Not only do you need the fat wire to carry the current safely, you don't have much room for voltage drop. Dropping 5V on 120V under load isn't a big deal, dropping 5V on 12V under load is literally unusable for most devices (12V stuff won't run on 7V). If you run something sane, like 48V or so, then you still need conversion electronics at each point of use, and you don't gain much over just running 120/240VAC, except that now your converters are really expensive because they're less common and "weird." 120VAC to 5V is super common, 48VDC to 5VDC is less so. Some switch mode power supplies will work on DC, some won't, and it's harder on the bridge rectifier diodes, so they don't tend to last very long in that sort of use. It's the sort of thing that sound good in isolation, but in practice leads to spending a lot of money to gain little or nothing in terms of efficiency. The exception is for a small system where you can run 12VDC to LEDs and stuff (think a camper), and avoid bringing the inverter online at all. Inverters have a significant idle draw more or less proportional to peak power delivered (my 2kVA inverter idles at 30W DC, a 6kVA one that can hold 18kVA for 20 seconds idles at 100W DC).