Well… Maybe not the MOST awkward…
Hard to believe that was built by the same company that made the Blackbird.
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New York had one neighborhood that was still DC powered up until around 1987ish. But the original Edison vs Westinghouse aka “Current Wars” was fought around the turn of the 20th century. Back then, there was no Transmission Grid and no one even envisioned one. All electrical grids at the time were local grids, aka “distribution grids”.
AC is much more efficient for several reasons. It allowed much higher voltage at a very reasonable cost as it used air as the insulator for the wires, and because high voltage meant lower current, the wires could be smaller and wire is/was expensive. It also allowed one set of wires to feed all customers despite their individual voltage requirements thanks to the use of transformers.
The early transmission grids were primarily made up of a single power station out to nearby sub-stations that served the local distribution grids. AC worked perfectly fine for that as well, no real advantage to switch to DC.
However later in the century, the transmission grids started to be interconnected so that excess power from one power station could fill in shortfalls from another power station. If they were close together, the only issue with AC was syncing the AC sine waves.
But as the transmission grids grew to include more power stations and cover larger areas, syncing becomes much more complicated. As the AC power goes down a transmission line, its phase changes relative to the power station. This gets even more complicated as wind and solar start joining in.
For example, I worked at a wind farm in central California as a consultant. It was feeding power to LA. The wind farm was about 200 miles away from the substation in LA that it was feeding to. All of the inverters at the wind farm were synced to the power signal from LA. That power was about 23 degrees behind the signal in LA because it took just over 1 milli second to trave that distance. The inverter sends the power back to LA but by the time it gets there it is now 46 degrees out of phase with the power on the LA distribution grids.
Imagine trying to get thousands of power stations across the country to all sync, it is impossible. DC does not have that problem. It uses local inverters to sync to the power at the substation. This is why DC transmission lines are starting to replace AC lines for the long haul networks.
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I can confirm this.
I had two relatives who lived on the Upper West Side of Manhattan, and they had DC power up through–at least–the early '70s (when they died), despite the fact that every other part of NYC had been converted to AC power many years prior.
Manhattan’s UWS–and the adjacent Harlem neighborhood–were “low income” in those days, and it was obvious that the local power company (Consolidated Edison) could deprive those areas of modern technology with no negative effect on their bottom line.
Luckily, in those days, Macy’s flagship store in Manhattan had a special department devoted to the sale of DC appliances. As a young child, I learned that if we wanted to buy an electrical gift for my Aunt Grace, or my Great Aunt Harriet, we had to visit the flagship Macy’s store, as they were virtually the only remaining outlet for DC appliances.
Looks like a Porpoise with wings.
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The love child of a blimp and a quad-rotor drone??
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Air Flipper
Service from Frankfort to Miami, 7 days a week!
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Those kinds of problems are not something the layman, even one with a strong electrical background, would normally consider being an issue. The scale changes the results considerably. Pretty interesting reason to gravitate to DC now that power electronics make it more feasible.
Sort of the equivalent of the Civil Engineering issue of designing very long buildings or bridges with the curvature of the Earth in the calculations.
RE the Airbus, I guess the cockpit windows are in the porpoise’s mouth.
Then we have NASA’s Super Guppy.
Incandescent light bulbs, heaters, and small series wound DC motors such as used in power tools and mixers work don’t care if they are powered by AC or DC.
I still recall having to go to the special “DC Department” at Macy’s flagship NYC store to buy small appliances and other electric items for my aunt, who lived in one of the few sections of the city that had DC power. This was in the '50s, and Macy’s was the only store that had a decent selection of those products.
We just bought a brand new Leaf today, our first EV!! There are 2 Volta chargers right across the street in the library/small movie theater parking lot. Their App shows if they are available or taken, so super convenient to run the Leaf down there for a free charge!
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