Plugs and power supplies

from LinkedIn discussion of power supplies:
The proliferation of wiring standards, plug-outlet combinations, and voltages/mains frequences is a major headache for designers, engineers,and users.  Unfortunately I doubt this will be dealt with any time soon, on a global scale.
A standardized system of low-voltage power supplies would be great, and could be implemented relatively easily.  While USB doesn’t have the capacity to transfer enough current for most devices, a set of power supply designs could be developed and standardized:
(1) a low-current supply for computer peripherals, mobile phones, etc.  USB could be used here, USB3.0 900mA power supply, and the battery charging specification could really be a good setup, allowing for lots of power transfer (up to 9W in power-only mode, 1.5A in low or full speed data mode)
(2) a medium current, low-voltage DC supply for things like laptops.  (20VDC, 5A powers my laptop).
(3) high voltage AC for standard household equipment like refrigerators, washing machines etc. Current 120VAC/220VAC mains supply
(4) high voltage AC for heavy equipment, like electric dryer, electric oven, electric car*
As much as I would like a new design for (3), the installed base is pretty much set, and for (4), a charging specification should be developed that is safer and easier to use than the current US 240V plug.  As electric vehicles proliferate, there needs to be some work done here.
for (1) and (2), standardization would be a great boon to society, as it would allow for interchange of power supplies among device users.  Most people where I work have Apple laptops of the same generation, and can share power supplies.  I’m the odd man out with the Dell.
I like the MagSafe connector, but it does have some drawbacks, like magnetic particles getting stuck to it, potentially shorting the terminals or interfering with the connection.  But in terms of usability it is pretty good, preventing your laptop from being swept off the table, or having the connector break on the cable or device.
A major benefit of standardization would be the ability to use one inverter/rectifier and transformer arrangement for all devices in a class (1) or (2), allowing for higher quality electronics to be used, and to have better switching, to reduce or eliminate standby power consumption.  Standby power consumption isn’t trivial, estimated to be hundreds or thousands of MW globally.  Standardizing the power supplies, and restricting standby power usage would go a long way towards combatting global warming, as well as reducing electronics production and e-waste.
Ideally in the future, there would be global standardization of mains voltage, frequency, and plug/socket pair.  I kind of like the IEC C13/C14 pair used on computers and other electronic equipment, and it’s pretty well standardized so far.  Unfortunately it doesn’t carry enough current.  Back to the old drawing board.

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