I am hoping this could be the right forum for this kind of question. I recently bought a house that is going to have major structural changes and an extension that will basically be new-build. I am pretty much a novice to all this.
I am thinking about the electrics, naively, and wondering what kind of cost savings and simplifications could be achieved by trying to run DC around the house.
My thinking is that
- I want efficient (LED?) lighting (DC)
- If necessary, perhaps I could pipe the light by cheap fiber optic, if that ends up being part of the solution
- Most things I use around the house either run off DC or will be rechargeable via USB anyway.
- I will still need a few AC sockets for things like the hoover, but not many
I am aware that low voltage DC will suffer voltage drop and power loss, and that fat cabling to compensate would make that more expensive, but what I am thinking is that because this is so early in the construction, are there any opportunities for taking advantage of decorative or structural elements as electrical conductors?
- Can I use steel reinforcements, even in steel-concrete, as the DC distribution network?
- Other structural and/or decorative elements such as aluminium bars, copper plates and etc., that when arranged could also serve as DC distribution
In short, in our current home it seems absurd at face value that we have all these little USB adapters and chargers lying around, transformers, wall-warts, bricks and etc., when it seems all I really need is a USB socket in a wall. I am wondering if there is any realistic way of achieving this that makes general sense.
Best Answer
Power losses depend very little on the type of current used (AC/DC), and much more on the voltage, which you didn't specify. Running 120V around your house will typically result in ~2% of power loss in the wires. With 40V, you'll lose 9 times as much, or you'll need wires which have 9 times bigger section area. 5V is only viable for very low-power applications.
Using steel structure to run your household current is a bad idea, as galvanic corrosion will eat the steel away very quickly. Running the current though indoors decorative elements is also a bad idea: imagine your DC converter fails in a way that gets high voltage into the output. Or a lightning strike. Would you feel safe in a home where you have to stay away from walls during a thunder storm?
What you can do is buy a big mains to 5V power converter, and put it in a wall with several USB wall outlets. Then you'd get a spot where you can charge your phones without the need for all these wall-warts. Just make sure the power supply is still accessible in case it breaks and you need to replace it.