The Future of Grid Power?

[Connecteur]

Let's say that grid power doesn't remain the same as it was originally designed about a century ago, more or less.  What would it look like with newer technology?

120VAC can be used in a lot of ways currently, but if the way it was delivered could change, how would it?  DC? Lower, safer voltages? Why not?  There was a time when AC power at lethal voltages made sense, but is that still the case? And will it be in the future?

And will the economics of scale always favor a large, centralized power plant?  Maybe every user could have their own power generation and storage, and do so economically.  Maybe we need no grid at all.  Power could be shared between multiple users, creating a "virtual grid," much less prone to outages.

I have mentioned USB as a possible replacement, and that may suffice for lower power applications, but something similar could be scaled up for stoves, dryers and electric vehicles. 

All I'm asking is if it were to change, what would it look like?

[Someone]

3rd time's a charm?
https://www.eevblog.com/forum/chat/do-we-really-need-a-grid/
https://www.eevblog.com/forum/chat/will-ac-power-distribution-become-obsolete/

[Connecteur]

Nice you remembered, but some of my ideas needed an update.

[indeterminate]

It has already started
grids are being re engineered to be better preforming  bidirectionally
Small Towns being supplied by hundreds of kilometers of transmission lines are being split of as micro grids.
more houses are being supplied by three phase 400v for EV charging, running there heating & cooling and to be able to feed the grid with more roof top solar.
AC is easier to deal with.
Higher voltages = less current & smaller wires for the same amount of energy
Modern safety devices RCD's / Earth leakage devices make things safe for the consumer.
lo voltage DC like a USB supply will never happen , there is simply not enough watts.
we may end up with intelligent power points that do not switch on the high voltage unless everything is safe.

[Andy Chee]

120VAC can be used in a lot of ways currently, but if the way it was delivered could change, how would it?  DC? Lower, safer voltages? Why not?  There was a time when AC power at lethal voltages made sense, but is that still the case? And will it be in the future?

All I'm asking is if it were to change, what would it look like?

Any changes must still obey the laws of physics, in this case, the relevant law is Ohm’s law.

High power delivery at low voltage, implies thick heavy copper conductors to avoid resistance heat/voltage drop losses. 

It’s why USB-PD of 120W @ 5V is impractical and not supported.

I’m pretty sure you also ignored Ohm’s law in your other discussion thread.

[.RC.]

I sometimes wonder where all this copper is going to come from to electrify everything.

Or are we going to use copper coated aluminium?

[themadhippy]

Lower, safer voltages? Why not?

lower voltage= higher current and greater volt drop,  needing larger cables. 120mm² to run me kettle at 5v aint  gonna happen

[Connecteur]

120VAC can be used in a lot of ways currently, but if the way it was delivered could change, how would it?  DC? Lower, safer voltages? Why not?  There was a time when AC power at lethal voltages made sense, but is that still the case? And will it be in the future?

All I'm asking is if it were to change, what would it look like?

Any changes must still obey the laws of physics, in this case, the relevant law is Ohm’s law.

High power delivery at low voltage, implies thick heavy copper conductors to avoid resistance heat/voltage drop losses. 

It’s why USB-PD of 120W @ 5V is impractical and not supported.

I’m pretty sure you also ignored Ohm’s law in your other discussion thread.

Copper is not  rare metal, and I expect that the market can't remain cornered forever.

[Connecteur]

Lower, safer voltages? Why not?

lower voltage= higher current and greater volt drop,  needing larger cables. 120mm² to run me kettle at 5v aint  gonna happen

I was thinking more like 50V, but I never thought 5V was even a possibility for household current.  Current USB PD technology is already delivering over 100W by using higher voltages.  Speculation is that 240W systems are already a reality.

[Siwastaja]

3rd time's a charm?
https://www.eevblog.com/forum/chat/do-we-really-need-a-grid/
https://www.eevblog.com/forum/chat/will-ac-power-distribution-become-obsolete/

Reported to moderators as a duplicate thread. OP should be bumping one of their old threads with new ideas.

[tooki]

Current USB PD technology is already delivering over 100W by using higher voltages.  Speculation is that 240W systems are already a reality.

Speculation means guessing. We don't need to guess.

240W USB-PD was introduced into the standard 3 years ago, and the first 240W chargers have just begun to ship. 240W-certified cables have been out for years now.

[tooki]

Copper is not  rare metal, and I expect that the market can't remain cornered forever.

What do you even mean? Who has "cornered" the copper market?

What we see is that the rising cost of copper is causing huge amounts of it to be stolen, often out of running installations, causing tons of property damage. The last thing we need is to dramatically increase the amount of copper needed, just so that we can lower the household line voltage. If anything, we would want to increase the voltage and just use new connectors.

[mikeselectricstuff]

Lower, safer voltages? Why not?

lower voltage= higher current and greater volt drop,  needing larger cables. 120mm² to run me kettle at 5v aint  gonna happen

..and is also less safe than HV due to increased fire risk.
I suspect that connections increasing in resistance over time is far more common than insulation degrading to the point where there is a shock hazard

[mikeselectricstuff]

Within the home, distributing 50/60Hz to lots of individual LED PSUs makes little sense nowadays, especially if you then add phase-angle dimming, but hard to see any alternative emerging as a common standard

PoE is one possibility, though maybe a bit overcomplicated.

[Simon]

Let's say that grid power doesn't remain the same as it was originally designed about a century ago, more or less.  What would it look like with newer technology?

When would you like to start the comparison from? years ago AC generators being added were synchronized manually with oscilloscopes, the people that were good at it saved the building form a thud when the extra generator was added. But that was not even 100 years ago.

120VAC can be used in a lot of ways currently, but if the way it was delivered could change, how would it?  DC? Lower, safer voltages? Why not?  There was a time when AC power at lethal voltages made sense, but is that still the case? And will it be in the future?

I don't know? do you have an alternative to wires? You do realize that DC is impractical as things stand unless substations become fitted with very large 2 way switch mode converters which become more and more impractical (read exotic/expensive) as the voltages rise to the million volts used in some transmission lines? What do you mean by lethal voltages. "the grid" has voltages up to 1'000'000V, over 50V is considered lethal in most jurisdictions, so unless you have a way to defeat ohms law and transmit power at 50V or less then no I don't think we will stop using "lethal" voltages as the chasm from non lethal to the maximum we use is 200'000 times!

And will the economics of scale always favor a large, centralized power plant?  Maybe every user could have their own power generation and storage, and do so economically.  Maybe we need no grid at all.  Power could be shared between multiple users, creating a "virtual grid," much less prone to outages.

Yes! "large, centralized" is the definition of economy of scale. Maybe not as large but certainly a grid will remain. How on earth do you think every user having way more generating capacity than they need on average will be cheaper than the grid? that is literally the reason the grid exists. Your "virtual grid" is simply the grid we are starting to have that does not have to carry so much power across one stretch due to the more local sharing of power. But your idea of every man for himself is a stupid one unless the laws of the universe are rewritten.

I have mentioned USB as a possible replacement, and that may suffice for lower power applications, but something similar could be scaled up for stoves, dryers and electric vehicles. 

OK, and what exactly did you have in mind? are you still trying to take everything down to 50V? You want a stove that is say made up of 2kW rings to take 50A per ring? currently a 32A circuit is used for the whole stove in the UK, you will need 150% of that for a single ring..... The advantages would be ? apart from a staggering increase in the value of copper that will be needed in even larger quantities than it already is.

All I'm asking is if it were to change, what would it look like?

Change happens for a reason! you have not stated a reason for any change. You just sound like some idiot looking to put a product on Indiegogo that is a total scam and is fishing for ideas as he has no clue what he is doing technically and has only worked out that he can rip people off on the pretense of a product that cannot work.

If you can't post anything technically relevant I suggest you try some place like X for your ramblings, I'm sure Musk will hire you.

[NiHaoMike]

Within the home, distributing 50/60Hz to lots of individual LED PSUs makes little sense nowadays, especially if you then add phase-angle dimming, but hard to see any alternative emerging as a common standard

PoE is one possibility, though maybe a bit overcomplicated.

Just plain 48V would do the trick, a mere 10A would then be 480W which would be far more LEDs than would be necessary in most homes.

[coppice]

Copper is not  rare metal, and I expect that the market can't remain cornered forever.

Very few elements are actually that rare on the Earth. What is rare is high concentrations where they can readily mined. We are already running low on those for copper. As you try to extract copper from lower and lower concentration ores, the energy required to mine and refine it skyrockets. Currently copper is at a kind of sweet spot where its cheap enough to use, but expensive enough to be heavily recycled. We appear to be recycling about 75% of it. Unless that can be raised quite a bit, which might be another highly energy consuming process of concentrating small scraps of it, we will need quite a bit more copper each time we go around the cycle of make, use, wear out, recycle, and repeat. I hope you have plenty of cheap energy for that high copper using future.

[mikeselectricstuff]

Within the home, distributing 50/60Hz to lots of individual LED PSUs makes little sense nowadays, especially if you then add phase-angle dimming, but hard to see any alternative emerging as a common standard

PoE is one possibility, though maybe a bit overcomplicated.

Just plain 48V would do the trick, a mere 10A would then be 480W which would be far more LEDs than would be necessary in most homes.

IME plain 48V is rather more prone to arcing  than 24. Also the range of converter ICs becomes a lot more limited - for simple DC I'd go for 24V.

[Marco]

The grid is fighting last years battle. At the moment the operators are worrying that they have so much renewable energy and it's not reaching the main industrial hubs, so they build more interconnect.

The problem with that is, that if we move to a fully renewable generation, everywhere will most of the time either have too much or too little renewable electricity for local demand. You have glut, or night, or winter/dunkelflaute. In a glut everywhere will be in a glut, in a shortage everywhere will be in a shortage, what lies in between is almost irrelevant.

It makes more sense to move hydrogen around than electricity, the current grid is plenty with a "little" strategic battery placement to smooth out peak consumption.

[indeterminate]

50V is never going to happen.

I just did a rough calc and that would mean running a 95mm sq cable into the house.
Thats $46 per meter for the two cores, and nearly 2kg per meter.
Then the power companies poles and whirs would need to be massive , who is going to pay for that.
Your larger EV's are moving to a 800v main power buss and 48v aux bus with limited support for legacy 12v stuff
if anything i can see countries with 100>120v systems slowly phasing them out for 220v
Appliances that operate from 220>240v are cheaper than  there ~100v twins and if it is cheaper and does the same job guess witch one sells.

[RJSV]

   Virtual grids I could begin to picture but the configuring and management would be chaotic nightmare.
   Firstly,  the hardware would most assuredly be the existing cables, poles and buried cable.
Supposedly, there would be a balance, of power production with consumption.

[G7PSK]

Let's say that grid power doesn't remain the same as it was originally designed about a century ago, more or less.  What would it look like with newer technology?

When would you like to start the comparison from? years ago AC generators being added were synchronized manually with oscilloscopes, the people that were good at it saved the building form a thud when the extra generator was added.

In the 1920 and 30's alternators were synchronised using the dark bulb method, A a lamp or two was placed between the two machines and when the phases were in sync the bulbs no longer glowed, I have a book dating from the 1920's that goes into details of how to do this. Synchoscopes came along later.

[themadhippy]

A home automation canbus protocol that piggybacks the existing AC cable with in a building.

Many discussions amongst lighting  crew around the world have pondered  something very similar,why the hell cant they stuff the dmx/artnet on  the power line instead of having to  run a power and a control cable to every fixture . There has been one or 2 tries,avolite being one,but that was a bit half arsed.Come on martin/robe/farilite  incorporate something useful for a change instead of increasing the channel count for a bit of eye candy that might get used once

[themadhippy]

In the 1920 and 30's alternators were synchronised using the dark bulb method, A a lamp or two was placed between the two machines and when the phases were in sync the bulbs no longer glowed

That takes me back,i remember a factory with just that ,there was also a meter below the lamp that rotated the full 360^o,when the needle was at 12 oclock you were synced.

[RJSV]

   What would a smaller grid,  look like ?   Gridlette ?
  Let's say, 10 miles by 10 miles is one grid.  Roughly 4 km on each side, of a square land area.  You've added up all the inherent existing generating capacity, and, likewise all the residential 'apatite' for power, with a decent match.   Well, right there you are going to need to link that 'micro-grid' to a main grid, due to occasional exceeding generation ability.

   The other way, with enough or more capacity, the extra capacity is lost if you cannot push that onto the main network.  For a lot of that, the decisions, for allocations originally and ongoing would be complex.
   Make the claim, that AI will rescue the management, by deciding when, and if, power flows either to or from the big network.
That's largely done by one, private entity, (like P.G.&E. here in California.)

   Ok, say that one square can be managed.  Then what about urban regions, having easily NO capacity resources, at all.
Is there to be a criss-crossing network, of 'helper' feeds, to solve that imbalance ?

   All priced the same ?   What if 'Montalvinia' in Montana goes on STRIKE...in a producer's strike, for more compensation ?
We don't see something like that, here.

   How about, what if one region wants to hold out, for different set-up rules ?
Do we create the tyranny to impose systems, at one particular regions expense ?

[RJSV]

   Then there is the pesky, rather large NATURAL GAS pipeline network.   That won't be under the flexibility that electric energy transmission has, and is locked in as to customers and regions.
Plus that market is jeopardized by the calls for (gas) to be banned outright (by the time this shit gets figured out, and implemented.)

   Abandoning the natural gas infrastructure is aot of wasted capability.  I'd bet that 'they' wouldn't even care to sell the whole lot, to some disadvantaged small country !

[Kleinstein]

The changes that may actuall happen could be changing from 115 V to 230 V.  With RCDs the danger of lethal shocks got lower and isolation also got better. The higher current at 115 V in creases the chance for fires from bad contacts / thin wires. I have not seen the statistics, but chances are that there are more fetalities from fires starting from the electrical system than electrical shock.
Chances are the change would be slow, starting with 2 phase 115 V as 230 V and increasingly less use of the 115 V part and more use of 230 V instead. The US plugs are anyway horrible and a makeover would be a good idea. Common sense would limit the US plugs to some 50 V and 10 A.

Those paranoid may have a local 48 V or 24 V network in the house, but this would be nothing for longer distances.

If one would be free to redo the standards a logical step would be a slightly high frequency, maybe near 100 Hz. This would allow for smaller transformers and motors and filter capacitors can be smaller. Slowing down an AC motor is possible with more poles, but there is no easy way to speed up beyound 3000/3600 RPM for 50/60 Hz.  A higher frequency would also be a bit safer for those afraid of electrical shock - the current 50/60 Hz range is about the worst case when it comes to an electrical shock. Anyway I see little chance to actually getting a change in the frequency.

[Analog Kid]

The US plugs are anyway horrible and a makeover would be a good idea.

How so? I beg to differ. I use them all the time and they (at least the well-made ones) are just fine.

For higher current there are the different NEMA form factors, including locking plugs.

[G7PSK]

[quote

If one would be free to redo the standards a logical step would be a slightly high frequency, maybe near 100 Hz. This would allow for smaller transformers and motors and filter capacitors can be smaller. Slowing down an AC motor is possible with more poles, but there is no easy way to speed up beyound 3000/3600 RPM for 50/60 Hz.  A higher frequency would also be a bit safer for those afraid of electrical shock - the current 50/60 Hz range is about the worst case when it comes to an electrical shock. Anyway I see little chance to actually getting a change in the frequency.
[/quote]

Ferranti built his first systems in the UK at 90HZ not sure why they ended up at 50HZ here.

[themadhippy]

The US plugs are anyway horrible

Any particular one?

For higher current there are the different NEMA form factors,

certainly plenty of choice


and people think the european ceeform is complicated

[SiliconWizard]

Due to the skin depth, doubling the frequency is not a very good idea for transporting electricity.

[TimFox]

Aircraft often use 400 Hz to reduce the weight of transformers, etc.
This is a trade-off with the weight of copper.
At 60 Hz, there is a common rule of thumb that there is diminishing returns when using copper wire larger than 0.75 inch in diameter (due to skin depth), slightly smaller than 500 mcm wire (0.81 inch diameter).
At 400 Hz, that translates to about 0.29 inch (AWG 1).
Old-style railroad electrification was done at 25 Hz (Pennsylvania RR) or 16-2/3 Hz (Switzerland) to use reasonable weight on-board variable transformers with DC (brushed) motors.

[G7PSK]

Due to the skin depth, doubling the frequency is not a very good idea for transporting electricity.

Ferranti knew this and his transmission lines were tubular concentric ones at that, he demonstrated the safety of his system by having the foreman hammer a cold chisel through a high voltage line with no ham to the man holding the chisel, earth/neutral on the outside and live inside. I think the only problem was it was a single phase system but this was 1898 1901 era.

[NiHaoMike]

   Then there is the pesky, rather large NATURAL GAS pipeline network.   That won't be under the flexibility that electric energy transmission has, and is locked in as to customers and regions.
Plus that market is jeopardized by the calls for (gas) to be banned outright (by the time this shit gets figured out, and implemented.)

   Abandoning the natural gas infrastructure is aot of wasted capability.  I'd bet that 'they' wouldn't even care to sell the whole lot, to some disadvantaged small country !

CHP is the answer for cold climates. Absorption heat pump technology still isn't that great, so in practice most gas powered heat pumps are electric heat pumps plus generators. Separate it out and then you'll figure out the two don't need to be attached to the same building, in fact they can be many miles apart.

[madires]

The direction is clear: AC smart grid and long haul HVDC transmission. Smart grid means controlling power sources and loads.

[SiliconWizard]

I like the idea of decentralized power generation, but I doubt it's something manageable, at least in large and dense areas.
And, it would require ultra-safe power generators to allow many of them everywhere. Some think of solar panel installations, but that's not an answer to this. Granted that is safe, but that's an option more for individual houses, while the large majority of people worldwide living in large urban areas live in appartment buildings. Also, while that works rather well in very sunny regions such as Australia, not so much in others like the UK.

[TimFox]

One very important property of grids is redundancy, so that it is easy to recover function when one part of the grid generation goes down.
This does no improve efficiency under normal situations, but is necessary for reliability under abnormal or fault conditions.
An example from a few years ago:  in February, 2021 Texas was hit by abnormally cold weather with three serious winter storms in quick succession.
Since Texas, for political reasons, operates its own grid that is not connected to the two large US power grids, there was a serious power shortage when many Texas-located generation stations that were not well-winterized failed in the cold, coupled with high demand due to the weather.
A more reliable grid connection might have saved a few hundred lives.
If the only financial penalty for a utility to go down temporarily is a loss of customer revenue, the utility has little incentive to maintain reliability by extra investment.