Homepage Forums General Transition Issues Transition to DC

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  • #562
    Avatarmaihem
    Member

    What with FF most efficiently delivering DC and DC most efficiently powering most of our appliances now with the current solid-state revolution, and with the electricity supply able to distribute to the last mile, there is little need for AC mains.

    DC is much safer than AC, and it loses less in transmission as its primary means of leakage is via ion migration rather than electromagnetic radiation (and ion migration is very slow, and draws very little power as well as being mostly mitigated with modern materials).

    data-centres are now moving to DC server rooms, putting the transformers outside the server room, and reducing their losses hugely.

    Cyclical processes in both industry and the home, solid-state or otherwise, do not often have a sweet spot at 50 or 60Hz:
    audio 48KHz
    video 120Hz (v) / some KHz (h)
    steel presses – several Hz to (1/several) Hz
    etc

    Is there still any good reason to deliver 110V@60Hz or 230V@50Hz AC to the home or can we deliver 24V,12V,5V,3V,1.5V and their negative counterpart DC rails?
    Can we also deliver 400V/200V/100V/50V DC to industry?

    What EMF could focus fusion deliver?
    And while I’m at it, what would its internal resistance be?

    #3367
    AvatarAlex Pollard
    Participant

    Great post. I have thought that with deployment domestic solar panels there should be standardised DC voltages for household appliances. Thinking about it, it is crazy to have almost every appliance require its own little transformer. If you have tried traveling with a laptop, video camera, digital camera, and mobile phone you will know what a hassle it can be.

    One way to get standardisation would be to utilise the USB standard. Many small appliances connect to a USB port and recharge off it. Small appliances could standardise on the USB voltage. A larger voltage would be needed for more energy hungry non-recharging appliances.

    DC power could also reduce the problem of devices draining power in stand-by mode as they would not need to transform AC power 24/7.

    #3368
    AvatarTransmute
    Member

    Does DPF pump out DC?

    I don’t think there is really much of a motive to switch from AC to DC now with are exiting AC infrastructure in place, maybe for HVDC long range power transmission. True solid state equipment now allows us to easily change DC voltages which was the biggest reason why DC lost the AC/DC wars more than a century ago, but changing the infrastructure of all home utilities to DC is not going to be easy.

    #3369
    Avatarmaihem
    Member

    Transmute wrote: Does DPF pump out DC?

    AIUI, it is like rectified AC – that is you get a rising edge from zero then a falling edge, then nothing, then another rising edge, etc. This is easily smoothed to DC and really shouldn’t be sent over transmission cables (even short ones) directly but should be converted either to DC or AC.

    I imagine the first round of focus generators would have AC converters but due to the cost savings of DC at the point of use there will be great demand for DC services so people will pay for infrastructure upgrades in the cost of their energy. The cost will be low, look at how easily the UK installed cable TV infrastructure. Demand was not even all that great.

    Let the DC be supplied from the focus generator at a high voltage and let each house have DC steppers.

    #3370
    AvatarTransmute
    Member

    maihem wrote:

    Does DPF pump out DC?

    AIUI, it is like rectified AC – that is you get a rising edge from zero then a falling edge, then nothing, then another rising edge, etc. This is easily smoothed to DC and really shouldn’t be sent over transmission cables (even short ones) directly but should be converted either to DC or AC.

    I imagine the first round of focus generators would have AC converters but due to the cost savings of DC at the point of use there will be great demand for DC services so people will pay for infrastructure upgrades in the cost of their energy. The cost will be low, look at how easily the UK installed cable TV infrastructure. Demand was not even all that great.

    Let the DC be supplied from the focus generator at a high voltage and let each house have DC steppers.

    Converting every peak into DC would require titanic caps or batteries, As is the caps are already needed so enough said about that, The question then becomes how much cheaper (so you claim) would be dumping the DC on to a new DC power distribution network (add in the cost of replacing the existing network) using new DC steppers to step the voltage down for homes, using new appliances in every home that can run off DC, the logistic alone say that converting to DC now would be hellishly not worth the price of having an AC converter at the reactors,

    #3371
    BreakableBreakable
    Keymaster

    Interesting idea is that the DC network itself in some circumstances can act as a gigantic capacitor.

    #3409
    Avatarwillit
    Participant

    good thread.
    although replacing existing 220/110 60hz power might be more efficient it would be a major investment by the average consumer in replacing all of their existing ac goods into a dc format. not to mention the cost to manufacturers in redesign of their product lines, standardization of voltages distribution of said voltages and overcoming the difficulty of even moderate distance voltage drops. this could be the realization of Edison’s dream of a dc distribution network that was shot down by Westinghouse and Tesla. in a transition to dc there could be benefits to dual service. but for the average consumer fast change would be economically unfeasible. imagine the workforce of electricians required to rewire neighborhoods and individual houses not to mention sky scrapers and industrial facilities, businesses hospitals ect. a major impact.
    ac has served us well for power transmission and industrial applications. could you imagine the use of 3 phase motors without ac. I have and looking at just the power requirements of dc vs ac ac wins. lower currents for a given horsepower which means smaller conductors and switch gear which means lower cost.
    society for the most part is resistant to change. they must have a worthwhile reason to convert to dc.
    $

    in the interim i believe that a shift from coal fired to fusion source of energy would have great impact on the use of energy as affordable it could become. heating or cooling dwellings electrically rather than gas, charging vehicles for commuting rather than fossil fuel, refrigeration costs go down decreasing food costs. all of these would greatly help out the consumer. with no change to the infrastructure that we currently enjoy.

    employing many substation generator facilities throughout our current network gradually would phase out coal fired plants along with dams, wind,solar, nuclear,tidal ect. this would give time for society to embrace the new technology while they feel zero impact on their lives other than a few more bucks in their wallet. it also gives time for exploring explaining the benifits of dc to the world and why it could be the next best thing.

    first and foremost we must create the viable equipment necessary to make the change to fusion (working on it) secondly the infrastructure could be modified to include dc but economics seem to dictate how and when that occurs. just because we conceive a better mouse trap does not mean that it will come into wide spread use especially when an old scrappy cat does the job.

    #3520
    AvatarJolly Roger
    Member

    I am buying an RV soon, and I would love to have appliances that run on AC or DC. If manufacturers made all appliances dual function, it would provide incentive to change the infrastructure to DC.

    “Built it, and they will come!”

    #3521
    BreakableBreakable
    Keymaster

    Jolly Roger wrote: I am buying an RV soon, and I would love to have appliances that run on AC or DC. If manufacturers made all appliances dual function, it would provide incentive to change the infrastructure to DC.

    “Built it, and they will come!”

    This seems like a nice new feature for appliances in 5-10 ears or so. Having solar battery system at home might help push for it sooner.

    #3523
    AvatarHenning
    Participant

    Jolly Roger wrote: I am buying an RV soon, and I would love to have appliances that run on AC or DC. If manufacturers made all appliances dual function, it would provide incentive to change the infrastructure to DC.

    “Built it, and they will come!”

    Appliances with dual input of 12V DC and 230V AC are available for decades. At least here in Germany. And they are actually used in RVs and homes with photovoltaic arrays.

    #3524
    BreakableBreakable
    Keymaster

    Great!

    #4086
    AvatarRematog
    Member

    Several BIG reasons for AC power.

    Transformers. They ONLY work for AC power. Very hard (therefore expensive) to raise or lower DC voltage. So if you have a, say 100,000 volt DC transmission line, how do you get it down to a usable household voltage.

    Motors. AC motors have no brushes to wear out. AC is much more convenient for making things turn, like say a refrigerator’s compressor, or the air conditioner’s compressor.

    Lighting. While conventional light bulbs will work fine on DC, fluorescent bulbs use ballasts to make the voltage they need to run. Guess you could use LED based lights, but those are not yet commercial.

    And the Biggest reason… Trillions of dollars in both utility infrastructure and industrial, commercial and residential equipment designed for good old 60 hz.

    Rematog

    #4087
    AvatarRematog
    Member

    Case in point about the persistence of standards…

    Look at your keyboard. QWERTY. It was created in the second half of the 19th century to SLOW DOWN typing…. to the speed that the manual typewriters of the era could handle……hmmmm.

    Going that one further. Why are the space shuttle solid fuel boosters the diameter they are….to be able to fit on a standard gauge rail road car….and, I quote wikipedia here, though I read this factoid before “Al Gore invented the Internet”.

    Early origins of the standard gauge
    Standard gauge appears to have been derived from the rutways created by chariots used by Imperial Rome, which everyone else had to follow to preserve their wagon wheels, and because Julius Caesar set this width under Roman law[citation needed] so that vehicles could traverse Roman villages and towns without getting caught in stone ruts of differing widths. Excavations at the buried cities of Pompeii and Herculaneum revealed ruts averaging 1,448 mm (4 ft 9 in) centre to centre.

    AND, bye the way, the chariot wheels were that far apart so…..a horse would fit between them….so…. The space shuttle solid booster diameter was determined by the width of a horse’s ass.

    I Love that one.

    Rematog

    #4095
    AvatarPhil’s Dad
    Member

    Along the same lines the specified distance between repeaters on early EtherNet cables was set to the standard distance between urban drain covers (in which the early lines between University buildings were laid). Makes you wonder were Big Al was when he invented this stuff. :smirk:

    #4365
    AvatarRezwan
    Member

    Phil’s Dad wrote: Along the same lines the specified distance between repeaters on early EtherNet cables was set to the standard distance between urban drain covers (in which the early lines between University buildings were laid). Makes you wonder were Big Al was when he invented this stuff. :smirk:

    Since it seems to be such a hot topic, I’ve assigned Al Gore his own discussion section (Al Gore Fan Club). Post about Al over there, and please try to keep such discussions out of your other posts.

    Thanks!

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