Home wiring/power of the future?

[LFMc]

Just thought I would start a thread on how we might want to power the home of the future. This is not about the grid, green or off grid power, but all that plays into it.  As I see my dependency on technology growing, I think about how I would wire/power home devices if I had it my way in the future and could start with a semi-clean slate. I know it is not going to happen any time soon, but it's nice to think about it and discuss it with other techies. Also I do not think "wireless" power is even a possibility.

I know everyone is fed up with the wall warts that multiply like rabbits due to most high tech needing clean DC power. Going back to the 1800's I know there was a battle between AC power and DC power. It reminds me of the battle between VHS and Beta that some of us can remember.  DC was the better product, but the transmission losses were too great for longer runs. AC won (and for other reasons, some very emotional) and now we're stuck with a power inside our home that has to be converted to DC for most of our toys and gadgets. Thus the problems with electronic noise, efficiency losses in conversion, WARTS, power supplies, etc.

So if I could start over, I realize that AC on the grid is here forever, but I think homes of the future should have a single converter at the breaker panel splitting up the home's power into two forms. Still have some AC power for major motorized appliances and maybe direct heating appliances (oven, range, ?) and have DC available at every wall outlet for everything else. Clearly there needs to be a range of DC voltages available, so power outlets could be wired for multiple voltages and the plug would determine the selected voltage automatically. So we'd have available 5/6V DC, 12VDC, 24VDC and/or 48V and possibly 96VDC. The thinking is higher consumption appliances would need more power so higher DC voltages bring on less current and therefore smaller wiring sizes. Think of POE and how there can be multiple voltages available to the end devices as an example. You could even have +/- voltages to get higher potentials at the device such as +/-48VDC = 96VDC.

Of course most our toys and other devices might have to be redesigned, but many devices now days already have a DC input port. Think of it, a life without warts, power supplies, less electronic noise and like Ethernet, the wiring could transmit high speed signals since there is no AC and much less harmonic/switching noise to muck things up on the wire.

Other benefits would be no dependency on 60Hz cycles, direct connection to solar panels with no inverter loss and well as direct connection to batteries and it makes a great power filter protecting the more delicate devices from grid issues. Have a power failure? Just crank up the car and plug in it's battery to the house DC grid. Built in generator in every home. Need more amperage, plug in the second car also.

I would enjoy hearing thoughts expanding on the topic.

"Old men dream dreams...." 

[mwester]

Alas, clean pure DC is just a dream...

One of the biggest issues is voltage drop, especially at the lower voltages.  You can mitigate this by running bigger, heavier copper conductors -- but that's really expensive.  Or, you can mitigate this by running higher voltages (e.g. Power-over-Ethernet, aka PoE, uses 48v on the cable).  Since most electronics -- and what doesn't have electronics these days? -- run at much lower voltages, that means you need something to do the voltage conversion.  And, to get any efficiency at all, that would be done by a switching regulator... the same noisy, dirty thing that we have in all those wall warts.

That's not to say that we shouldn't have a lower-voltage DC bus -- something like a 24VDC or even 48VDC would make a lot of things easier and cheaper.  I think we'd still want UL and CSA approvals, but that's easier to get (translating to cheaper for consumers).  But I doubt that we'd find it much easier to send Insteon-like signals over that DC wiring, 'cause we'd have the same blasted el-cheapo junk switching power-supplies plugged into that DC bus.

So, to fix that, along with the extra wires for the DC power, I'd like to see a standard house signal bus (or two, or three).  The lower-voltage would probably permit one to pull signal wires into the same boxes along with the DC power (something you can't really do with current electrical codes with 120 VAC).  Heck, you might even be able to buy cables with the heavy-gauge DC conductors along with an RS-485 bus, a few twisted pair (for alarm or general purpose use), and a Cat-6 cable (appropriately shielded).  I know, you could do this today, but it would all require separate cables, and separate boxes -- thus vastly increasing the cost of the cabling.  I think this is critical because in the long run, we're going to rely on our home automation, and what we've learned from z-wave and insteon is that they're just too <bleeping> difficult for the end consumer to get configured and running in a typical house.  Heck some of us on this forum struggle to keep these things communicating.  So, hard-wiring is the way of the future, and adding that to a DC power feed just makes all the sense in the world.

Final thought -- why do we still want our lighting circuits to be at the same voltage as our wall outlets?  Perhaps a big lighting power-supply alongside the panel would make it easier and cheaper to put LED-based lighting where we need it.  The idea of an individual switching power-supply in the base of every light bulb seems to be such a waste of natural resources to me -- I'm looking at my kitchen right now, with 12 high-wattage LED floods -- each of which duplicates the same power-supply.  Seems to me that feeding them all a standard DC voltage, with a standard 0-10v control (dimmer) voltage, would be so much more efficient in terms of size, heat, and the resources to manufacture the things.  (And again, note that the 0-10v control signal is a commercial standard for dimming -- the idea of wired controls using a low-voltage signal instead of switching 120VAC just makes so much sense!)

[LFMc]

8 minutes ago, mwester said:

Final thought -- why do you still want our lighting circuits to be at the same voltage as our wall outlets? 

Great points. Technology is using less and less power, so need for more power/current/wire gauge is decreasing in my mind. Also, if you give something 6vdc and it only needs 4.8vdc, you are so close they could probably use simple resistance to down convert the voltage because the power is low and there for the I2R losses are minimal. Simple and clean.

I too thought of a power buss thru the house with taps for outlets, etc.

[LFMc]

Also, PLMs that last 10 years, or indefinitely, instead of 2 years...

Sent from my XT1575 using Tapatalk

[larryllix]

Most electronics require lower voltages to operate. To transmit around the house would create some problems. Higher power loads would create voltage drops and require heavy copper conductors and/or cause sensitive loads to crash with lower voltages.

Now overcurrent protection becomes almost impossible. would we fuse that circuit for the small computer/monitor  requiring 50 watts or the USB charger requiring 2.5 Watts? Do we run hundreds or radial fed lighter wiring for every possible device in the house at different locations or just heavy duty DC (ring) busses and outlet fuses like UK house wiring? I am sure this would end up being 24 or 48 vDC and require inverters anyway.

Then there is isolations between devices. Some devices would not like being on the same feed bus and another device and the isolation of a switching regulator would alleviate most of those problems. Some device could pick up static or a lightning shot and the whole house would need replacing due to no ground conductor isolation on a shared direct connect power supply between sensitive circuits. Operating inductive loads such a relay coils can be nasty to send back down a supply line.

 

I don't see us eliminating power supplies of some sort for isolation, regulations, and filtering purposes, unfortunately. Electronic power  supplies are getting very tiny, efficient and cost effective.

 

@LFMc. Obviously you are an electrical guy. You spell a common conductor run ('bus') after the fuse company name "Buss".  

[Mustang65]

You happened to hit one of my touchy subjects.... wall warts. Example, my 16 Security cameras have (6) 5 volt 1.5A wall warts and use 4to1 adapters, some only can power 2 cameras. Great for the older cameras. Newer cameras have more IR LED's.. more amps, so the wall warts were dropping one by one. Yes they have those main control power centers for security cameras but a lot have bad reviews and have a limit of right around 10 amps. When the wall warts start to die they get hot and the current drops, even on the newer wall warts. I decided to build my own power source for the cameras. Another reason for the build was that I wanted to be able to reboot the old cameras that had an issue of shutting down, so I incorporated an Arduino into the new power unit. I included a picture of the up and running unit. It also is connected to my Netscreen GT5 VPN box, so that I can access it remotely and reboot cameras. Also, Since there is a 16 camera limit, I can add additional cameras (16 more if I really wanted to and switch back and forth) that I can activate/deactivate using the Arduino.

My current project is a 110vac/24volt/2Amp transformer inside a 4x4 electrical box (next to existing 110VAC outlet) with a custom wall plate that has (1) RJ45 receptacle (CAT5), (1) 12VDC plug (Wi-Fi/Router), (4) 5VDC plugs (replace wall warts). It has a DC/DC 24/12 volt regulator and a 24/5 volt regulator. This is for my Media center. I could add a ESP8266 to monitor DC voltage and current, but that would be a phase 2.  Wait, it would be easier to just run a new 110vac leg to power the new transformer and add the leg to the GEM to monitor the current and set up a program in ISY to notify me if there is an issue.

 

 

[LFMc]

2 hours ago, larryllix said:

Most electronics require lower voltages to operate. To transmit around the house would create some problems. Higher power loads would create voltage drops and require heavy copper conductors and/or cause sensitive loads to crash with lower voltages.

Now overcurrent protection becomes almost impossible. would we fuse that circuit for the small computer/monitor  requiring 50 watts or the USB charger requiring 2.5 Watts? Do we run hundreds or radial fed lighter wiring for every possible device in the house at different locations or just heavy duty DC (ring) busses and outlet fuses like UK house wiring? I am sure this would end up being 24 or 48 vDC and require inverters anyway.

Then there is isolations between devices. Some devices would not like being on the same feed bus and another device and the isolation of a switching regulator would alleviate most of those problems. Some device could pick up static or a lightning shot and the whole house would need replacing due to no ground conductor isolation on a shared direct connect power supply between sensitive circuits. Operating inductive loads such a relay coils can be nasty to send back down a supply line.

 

I don't see us eliminating power supplies of some sort for isolation, regulations, and filtering purposes, unfortunately. Electronic power  supplies are getting very tiny, efficient and cost effective.

 

@LFMc. Obviously you are an electrical guy. You spell a common conductor run ('bus') after the fuse company name "Buss".  

Got me on the bus...  I'm an M.E. but worked on many military air-frame designs/weapon systems. So the electrical has been absorbed by osmosis. 

I am sure things with a whole house DC bus aren't perfect, but I think with a single large DC converter at then entry to the house with good iron isolation transformers, etc. there is not going to be much , if any, external noise getting in on the DC side. So then you have to deal with some internal noise, but filtering for DC has to be so much easier than AC. But if most of the switchers are on the AC side, noise is not as much a problem anyway.  

I just don't think that voltage losses would be a big deal as you are looking at short runs for most homes. Also most devices are designed to run over an input voltage range that obviously can vary. I am just a dyed in the wool believer in the K.I.S.S. principle. fewer components = fewer failures and problems.  But in the end, I have to know my limits on E.E. design work and admit others know a lot more than I do about it. 

 

 

[Teken]

There has been a very slow and steady move toward induction which Tesla proved years ago as the key method to power almost anything at any distance. Apple demonstrated a hybrid system which could charge a iPad from more than 25 feet away. What I thought was interesting was how clever and not so clever the engineers were in their method. Essentially in this make belief multi room was several of their key products from iPhone, iPad, iPod, and Monitor.

As always, who ever it is they use to make the demo video's are true artists and genius in show casing the product and their technical prowess.

Watching the demo video was like watching and listening to a beautiful symphony . . .

The whole time you're watching this video random people are seen picking up the Apple products using, playing, listening, working.

Later people are just talking, watching TV, doing dishes, taking a shower, what ever . . .

I'm like WTF am I supposed to learn, see, know here?!?!?

What these freaking genius did was show me, you, and the entire world that technology can be sexy, seamless, and hidden. In the end (of course) they break down the fact during an entire 24 hour period none of the devices dropped 1% in terms of battery power?!?! That the *Human* while in their home / where ever if properly equipped in this case there were paintings which you guessed it (maybe not) because I didn't!!  

Were the high frequency output power inductors which strategically placed allowed seamless transfer of power to any room, device, etc. The Apple devices of course had built in coils to receive the high frequency power transfer. None of the smaller devices on the face of it impressed me that much besides the fact it was seamless. None of that stupid induction pads, or goofy sleeves I see people use.

It was the four giant sized Mac / Mac Pro computers that easily consume 100 ~ 1200 watts.

Those giant and power hog computers were being powered directly from the wall art, table, book ends, to what ever that ugly light shade they had up. I know this is hard to understand unless its seen but envision a 4K video being played on one of those beautiful monitors. The video is five minutes long and the camera pans in to show case X / Y video of what ever. There is a clock that shows tenth of a second like you see in high security NVR's. This is done to ensure video is not altered and the time stamp is true in fidelity. What these people were trying to impress upon the tech geek that knew what the hell they were seeing is at no time did the clock stop, freeze, jitter, or pause. 

I have suspect that the monitors were modified as it's typical for such hardware like amplifiers to have some kind of ultra capacitor buffer. This would help store, buffer, and release the energy in a seamless manner that would not impact how the system operated. One of the key things which I realized from the over view is how they impressed upon the viewer that nothing changes in your life and its dead safe.

High frequency induction at long distances exceeding five feet is extremely hard to do with out impacting surrounding electronics, human, etc.

No one had frizzy hair, no one was wearing as far as I could tell special foot wear, or some kind of grounding brace.

When you induce 50, 000 ~ 150, 000 volts into the air you better have a solid and good exit strategy for *Human*.

Otherwise *Human* will be a crispy cream once he becomes ground to something else . . .

Anyways, quite a few years ago on TED Talks there was a scientist who show cased a new tech which used light to transmit any data stream. You can see it still on line and when you see what they have been able to accomplish this will remove the need for wires in terms of data transfer and communications. Anywhere there is a LED light it can broadcast the information and of course the side affect of this technology is extremely high security!!

     

[apostolakisl]

The DC voltage loss is quite a problem.  The runs would be very long even in a small house when you figure all the circuitous routes that are often needed.  I had to use 10 gauge wire to get my IP camera to work properly when I extended the wire to 25 feet.  It is a 5v camera that pulls about 1 amp.

I just don't see DC voltage in the house ever working.  The cost of running all those wires of different voltages all over the place, 98% of which you probably won't ever use would be quite high.  It would be one thing if every electronic device in the world agreed to run on 9v or 12v or whatever, but that cat is out of the bag on that one.  Even if they decided today to all go with something like 12v, it would take a decade to flush out all the older stuff.  Even at 12v it is a problem.  Just ask the guys who make cars about how much all the wires in a car weigh because they need so many amps when only running 12v. . . and that is in a care . . . .where the longest wire run is maybe 15 feet.  Compare that to a house with wire runs measuring in the hundreds..  I was reading a few years back that the auto industry was going to switch to something like 48 volts, but it doesn't seem like it ever came to be.  

I am pretty secure in the idea that the way to handle this is to keep improving the AC/DC wall wart technology for smaller, cleaner, more efficient devices.  Maybe ones where the "wart" isn't really any bigger than the standard lamp plug.

[larryllix]

The lower the voltage system the more susceptible it is to noise. Higher voltages are used in many systems due to making the noise figures relatively small in comparison to the system voltage.

WallWarts can give isolation between appliances, especially where distances are involved and voltage gradients can be introduced that could burn low voltage appliances out. A few voltage drop on an AC neutral, grounded in two places could induce that few volts into a low voltage system and cause havoc. This happens in power grid systems and many farmers know of it as "tingle" voltage that can kill farm animals or stop them from ever drinking water again if they get a poke in the mouth due to voltage ground gradients. Isolation is the cure mostly.

At least in a 12v car system you have a metal cage around the whole system and it is short.

[Mustang65]

Thinking down the road….

Reengineer the below 3 pin XLR Audio outlets/plugs to handle LOW voltage 5VDC, 12VDC, GRD, or the 5-pin version for 3.3, 5, 12, 24VDC, GRD. This would make a GREAT LOW voltage standard outlet/plug.  Maybe just use a 2-pin model with 24VDC and GRD, and the electronic devices would have the proper voltage regulator in its circuit. These outlets would also have 2 USB outlets. There are a lot of items that could use these outlets… LOW voltage LED table lamps, Voice control units, AP’s, Apple TV….. and a media center version, anything using a wall wart in this voltage range. 

Each of these outlets would have a circuit breaker for each voltage. Depending on the Amp rating of the unit purchased you will have a 1 to 3or5 outlet plug, to distribute power to one or more items from a single LOW voltage outlet. Or maybe a wall plate that has 4 of these 3/5 pin outlets.

As for a supply voltage, you could strategically locate LOW voltage distribution boxes in the attic/basement locations of the house, breaking down the houses into smaller supply areas. The distribution box would be fed by 48Volts DC from a Main DC service panel, which would get its power from Batteries powered by SOLAR, with an 110VAC backup power supply, or just the AC powered DC supply. The voltage drop would be minimal on the 48 Volt feeds (proper AWG) and 24Volt wall circuit drops, and have 2.3, 5, 12VDC voltage regulators designed into LOW voltage wall assemblies. Much easier that way.

As for a transition from wall warts to the new standard, since wall warts have low voltage plugs at one end, you sell 3/5 pin adapter cables to replace the wall warts.

My RV, which has not used the RV’s 110 VAC battery charge controller for 6 years now (AC breaker is turned off), has 250 watts of SOLAR and 260Ah’s of Trojan T145 (6) volt deep cycle batteries. Cares for all the 12VDC loads and occasional Micro Wave use when dry-camping. The SOLAR panel’s 35’ cable run (10AWG wire), at 36.5 volts is less than a .1Volts at the MPPT charge controller termination. The below picture was taken around 5pm, so it was still producing. In the best SOLAR part of the day the MPPT controller pushes out a max of 19.5Amps, if the batteries need it. 

Since I am working on a low voltage solution for my media center, I may rethink my original design and work on this as a proto type. It would be an interesting project.