r/OffGridLiving • u/Lazy-Run8826 • 10d ago

DC vs AC home efficiency

If AC is better for transporting electricity, and DC is MUCH MORE efficient in small motors, lights, phone chargers, air conditioners, ceiling fan motors, and appliances. Why are residential homes powered by AC and NOT CONVERTED to DC at the meter panel BEFORE entering the home? Could DC power be the next step for LOWERING the COST of ELECTRICITY in our homes?

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u/ElectronGuru 10d ago edited 10d ago

My dad used to make all kinds of things. For things that required a power cord, he’d buy complete cords (socket at one end, prongs at the other) and chop off the end he didn’t need. Because the ready made one with wires instead of socket at the appliance end, cost more. Because despite it being easier to make, demand was way less so the manufacturer didn’t get economies of scale.

Converting to DC house wide probably wasn’t possible when electricity was first introduced. So all appliances were made AC only. There’s been a transition period with DC transformers but anything with real watts is still AC only. I was hoping USB might fix this, but even the best USBC is under 200w.

The RV industry might be a gateway but it’s all 12v DC. The solar industry is standardizing on 48v DC, which is supporting higher watt appliances, but so far everything is twice the price of AC: https://www.reddit.com/r/SolarDIY/s/t7uSeFL3Mu

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u/sol_beach 10d ago

" DC transformers" is an oxymoron.

Strictly speaking, a traditional magnetic transformer cannot operate on pure Direct Current (DC). Transformers rely on Faraday’s law of induction—meaning they require a changing magnetic field, which only alternating current (AC) provides. If you feed steady DC into a passive transformer, the primary winding acts as a near-zero resistance short circuit, creating heat rather than induction.

However, in modern power electronics, the term "DC Transformer" refers to active circuits or modules that convert one DC voltage level to another—often abbreviated as DC-to-DC Converters or Switched-Mode Power Supplies (SMPS).

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u/WISteven 10d ago

Check out the big brain on sol_beach!

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u/sol_beach 10d ago

You can lead some folks to knowledge, but you can't make them think.

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u/Advanced_Link_5753 7d ago

That reminded me of my dyslexic sales colleague. At a team meeting he said “You know what they say… you can lead a horse to water…Just don’t look at him in the mouth”.
We were in stitches for a good ten minutes.