When Thomas Edison tested the first lightbulb, where did he plug it in?

[Spectre of Pithecanthropus]

Ha, ha, just kidding. I think he used a battery. Seriously though, who can tell me about the origins of the electrical infrastructure that we so much take for granted today? When
did various appliances such as toasters and electric ovens become available? When were the voltages of outlets standardized, and the wattages of bulbs? I happened to
see a vintage 1912 lamp on an antiques show, and they said
it had all original wiring.

Also, how expensive was electricity compared with today?

[Saint Zero]

Hoo Boy, you've hit on one of the great wars of the 20th century. AC vs DC. In this corner, the misunderstood genuis, Nikola Tesla! And in this corner, carrying the banner of Direct Current, the man with the backing and PR, Edison!

Seriously, it's been ages since I did my paper on this, but the gist of it is both battled for their prospective ideas (with Edison actually inventing the electric chair). Who would have won is kinda moot. Tesla gained a backer in the name of Mr. Westinghouse, of General Electric fame. They were the first maker of generators, and they adopted AC as their standard. AC eventually won out. I don't have my books or I'd write this up better.

Tesla also invented Radio, did you know that? :)

[carnivorousplant]

Edison was able to say, "Joe Blow was Westinghoused to death at the state prison yesterday."

[jwg]

The only answer to your bunch of questions that I can remember is that a single light bulb, when electricty was first piped into homes, might cost anywhere from $2 - $10 to run for an hour or so. That's why your parents were always on your case to turn off the damn light. Because the great grandparents were on the grandparents case and the grandparents sure as hell were not going to let your parents run wild. And do you think money grows on trees young man?

[LouisB]

After my father retired, he got bored and secured a job taking people on tours of the Edison winter home and gardens in Fort Myers, Florida. The home itself is, IIRC, the first pre-fabricated house in America. It was built somewhere in N.J. (I think) and then cut apart, shipped to Fort Myers and re-assembled. As part of the tour, people were allowed to go through Edison's workshop and for a long time, one could pick up and examine chunks of the synthetic rubber Edison developed. Now the workshop is fenced off and people are no longer allowed to do the hands on thing. In that workshop are lightbulbs that were built there. They actually still work and are turned on at least once a year just to demonstrate that they do. Edison's Model T Ford is still there and is driven once a year during the Fort Myers Pageant of Light--a parade and general tourist trap event honoring Edison. Edison touted Fort Myers to such an extent that eventually Henry Ford and Harvey Firestone bought estates on either side of Edison's.

For a long time, there were a couple of old men who had actually been employed by Edison who hung around and chatted with people. Saint Zero, those old guys got livid over the mention of Tesla. It seems that Thomas Edison really had it in for Tesla and indoctrinated all his employees to be anti-Teslaites. In fact, my father picked up the anti-Tesla syndrome just from hanging around these guys. Sort of funny since he was an accountant all his life and about all he knew about electricity was that turning on a switch caused the light to operate.

If anyone here ever gets to Fort Myers, the tour of the Edison place is well worth taking. The Firestone and Ford estates are now city owned and are included on the tour. There is a museum on the premises with many early electrical appliances on view. Admission to the museum is included with the tour.

Sorry for rambling.

[stuyguy]

My sincere apologies for the halfbaked insights that follow. Hopefully someone with all the details will weigh in (pun intended, as you will see) soon. Away we go...

You asked about the price of electricity in the good ol' days. Well, I believe that back in the g.o.d. there were no such things as numeric electric meters (that would tally up household consumption) that we have today. Instead, the feed from the electric company passed through these liquid-filled contraptions which (I'm guessing) looked like wet-cell batteries. The more juice you used, the more (or less, I forget) solid stuff came out of solution and deposited on the "electrodes."

The "meter readers" of yore would WEIGH the solid stuff to figure your household electric consumption for that period.

I hope I got most of that right.

[bibliophage]

When Thomas Edison tested the first lightbulb, where did he plug it in?Just to pick nits, Edison didn't invent the electric lamp. Humphry Davy invented the electric arc lamp before Edison was born. In the U.S., Edison usually gets the credit for the first practical electric incandescent lamp. In Britain, however, Joseph Swan often gets the credit. Swan produced a light bulb in 1860 that was impractical only because he couldn't make a vacuum good enough. Both Edison's and Swan's practical incandescent lamps came out in 1880, when vacuum pump technology had improved.

[egkelly]

The Edison museum in Ft. Myers is interesting and indeed worth the tour. Edison just didn't invent a practical lightbulb (Swan's were made with a platinum filament-not feasible to mfg.), he also masterminded the whole production and distribution of DC power-quite a feat for an uneducated inventor. The previous poster was correct-Edison fought Tesla on DC vs AC, but the fact remains that Edison solved the problem of practical electric illumination, in a way that is still used today (albeit with AC!). However, Edison was NOT a scientist-his lack of training led him down many blind alleys...and many of his chemical ventures (non-latex derived rubbers) were not commercially successful. He also lost a ton of money trying to mine iron ore in NJ-despite this, the man came up with alot of inventions that we use today.

[Padeye]

While DC didn't last as a distribution standard Thomas Alva plugged his first bulbs into the Edison socket, a standard that is still with us.

FWIW my mother grew up on a ranch that did not have utility power or telephone until she was long gone in the early sixties. Before then their electricity came from a wind charger tower and a basement full of lead-acid batteries. When the wind blew - a lot on the Montana prarie - they could leave lights on and iron clothes.

[Cartooniverse]

Um. Not to pick nits or anything, but NOBODY has actually responded to the OP Query. My understanding is that the first working incandescent didn't have a metal threaded cap, that would screw into a porcelain and metal base. ( Called to this day in my business an Edison Socket ).
It simply had the wires leading out from it, and they were attached to the proper source. I can't cite, I'm sorry. I remember this stuff from my ill-spent school days. Anyone have......like..... A LINK WITH A PHOTO? Surely the event was documented up the wazoo photographically.

Cartooniverse

[Padeye]

Well I did respond to the OP, but with an incorrect WAG.

[yabob]

One of the more bizarre wrinkles in the AC / DC fight was that Edison publically elecrocuted a circus elephant named topsy that had killed three people. He participated in this particular spectacle to demonstrate how dangerous AC was:

http://www.roadsideamerica.com/pet/topsy.html

[carnivorousplant]

http://history1900s.about.com/homework/history1900s/gi/dynamic/offsite.htm?site=http://www.nps.gov/edis/wrlist.htm

Gee, I hope this works.

[Engineer Don]

<Sort of a Hijack>

The elephant wasn't the only thing. Look into the first use of the electric chair in New York. In short, Thomas Alva made damn sure that "the Chair" was AC, and he didn't do it by purchasing influence. It took a few zaps to do the job, and it was appearantly very unpleasant looking, smelling, etc for the witnesses. No one could doubt that AC power was deadly (not that DC won't hurt you.)

Also, Tesla worked for Edison when he came up with the AC that we all love so dearly, but was let go 'cause he wore suits instead of greasy overalls, and Tommy hated that. Westinghouse hired Tesla, bought his patents cheap, fired him, and then ended up selling equipment built with Tesla's patents to Edison.

A little later, Tesla goes barking mad (Obsesive / Compulsive) and starts working on a deathray. Tesla's life is pretty interesting when he goes wacky, but Edison was kinda loopy too in his last days. He got into spiritualism and lost his edge. I get the impression that the AC verses DC thing really bothered him.

What is funny is that DC is now used for long distance high voltage transmission, so Edison is sort of vindicated.

Back to your question, though, do a search in the book stores. There are tons of books on this stuff including my favorite white washed version "Iron Men and Copper Wires", by William A. Myers. For the scoop on Tesla's OC thing, "Strange Brains" is pretty cool. Read the bio's with a grain of salt. Newspaper articles from the period are the best way to get a good handle on what was going on, although the "Yellow" journalism period kind of overlaps the start of the electric companies.

[carnivorousplant]

Don,
You said:

"What is funny is that DC is now used for long distance high voltage transmission, so Edison is sort of vindicated. "

I thought there were large resistive losses with DC over a distance.

[Saint Zero]

Louis,

Fascinating. If I ever get down there, I'll have to stop by and ask about him. ;)

[friedo]

Originally posted by Saint Zero
Louis,

Fascinating. If I ever get down there, I'll have to stop by and ask about him. ;)



This is what I heard as well; the reason AC won out is because it is much more efficient over long distances, which was the requirement. DC was OK for a little coal generator powering a two-block town, but not for a giant powerplant powering an entire county.

I know the NYC subways had their high voltage current delivered AC, which they converted to DC (with a rotary converter) for the trains (variable-speed AC motors hadn't been invented yet, so you used a DC motor with a bigass potentiometer.)

[Ranma]

Don, I live in Québec and I know for a fact that high voltage(735Kv) transmission lines are AC. DC had big difficulties for traveling long distances, and Edison's plans were to build DC producing powerhouses everywhere (of course those power plants would have used coal for fuel, wich would have been very polluting, vs Tesla's AC current which production was demonstrated at Niagara Falls by a hydro-electric power plant) to palliate for the lack of transportability, instead of having fewer power plants and having long distance transport. Edison tried every way possible to discreditate AC (including public demonstrations of frying various living creatures with AC, trying to demonstrate how AC was dangerous, of course without saying that DC would have done roughly the same thing), but eventually got overwhelmed by AC, being much more practical. As for Tesla's "death ray", it was alledgedly a device made to shoot down planes by particle projection. It would use very fine ionised metal particles, projected forth by repulsive electromagnetic force.(a bit like today's railguns. So that was the concept, but I have no information as to if it was ever fully operational)

[scr4]

Originally posted by carnivorousplant
"What is funny is that DC is now used for long distance high voltage transmission, so Edison is sort of vindicated. "

I thought there were large resistive losses with DC over a distance.

I think resistive losses for a given transmission line only depends on current. AC is more "efficient" because you can use simple transformers to increase voltage. This decreases current (10,000V 1amp carries the same power as 100V 100 amp) which reduces resistive loss. With DC, it's much more difficult to change the voltage.

I haven't heard about DC used for transmission either. Can someone shed a light on this?

[KeithT]

Originally posted by scr4
I think resistive losses for a given transmission line only depends on current. AC is more "efficient" because you can use simple transformers to increase voltage. This decreases current (10,000V 1amp carries the same power as 100V 100 amp) which reduces resistive loss. With DC, it's much more difficult to change the voltage.


That's exactly why we've used AC for 100 years. However, as you raise the line voltage, inductive resistance also increases. The 60Hz oscillation of electrons back and forth in the wire generates a pretty good amount of heat, and therefore power losses. (Any EE's want to help me with the formulas?) Now that we know how to invert and rectify and otherwise adjust DC voltages with low losses, DC transmission is being used for very high voltage transmission (1MV+) over long distances, particularly in California, IIRC.

[sailor]

>> DC transmission is being used for very high voltage transmission (1MV+) over long distances

This is correct. At such voltages and distances, AC losses become too great. i am not sure how they do the AC/DC and DC/AC conversion but it must be pretty interesting.

[Engineer Don]

Keith T. & Sailor are 100% correct on the AC/DC thing. DC is used here in California only for very high voltage long range transmission, specifically to connect two systems operating at different frequencies, usually with either long underground or underwater sections. The DC lines are over 500 miles long, and while at first they were 700,000 volts, now they are all 1,000,000 volts. Under these conditions the line losses are less than AC, the towers are cheaper, and there are only two conductors, so the wire is cheaper. Drawbacks are that the converter stations (a rectifier for AC to DC, and an inverter for DC to AC) are really expensive and it isn't cost effective to have any radial feed circuits running from the main line.

I also want to be clear that I wasn't saying that it turned out Edison was right and Tesla was wrong, 'cause clearly that isn't the case. AC is definitly the way to go for all but very speciallized long range transmission.

During the AC verses DC thing Edison did horrible things in a futile attempt to discredit AC power. His behavorial changes following that lost crusade show how deeply it affected him. Most biographies of Edison gloss over this period, and focus on his earlier successes. Edison said "genius is 10% inspiration and 90% perspiration." I always thought people that sweaty shouldn't work around eletrical equipment.
Tesla was clearly a genius. His inventions speak for themselves. Later in life, though, after Westinghouse got really rich off of his work, he was, based on what I have read, nuts. Many such geniuses (constructive/inventive) were obsessive-compulsives, unlike the traditional artistic geniuses who tend toward manic depressive.
Edison, Tesla, and Westinghouse were all such major players in the development of electrical utilities that their personalities are key to understanding some of the decisions concerning our current electrical infra-structure.

[carnivorousplant]

I can't resist or...

They made a movie about power distribution staring Racquel Welch.

One Million Volts D.C.

:)

[Crafter_Man]

I wasn't aware some high voltage lines were DC. Interesting.

Most power distribution lines, of course, are AC. As many have already pointed out, the primary reason is because transformers can be used (transformers can't be used w/ DC).

But the FUNDAMENTAL reason is because insulation is cheaper than copper. Let me explain with an overly simplistic example:

Let's say you want to transfer 100,000 watts from point A to point B. A nifty way to do this is to use electricity. But at what current and voltage?? (Don't worry about AC vs. DC for now.) Power = Voltage x Current. So for a given power we can use a high voltage and low current (100,000 V at 1 amp, for example), a low voltage at high current (100,000 amps at 1 volt, for example), or anything in-between.

A high current at low voltage sucks because I^2R losses in the conductors become prohibitively large unless you use extremely large gage conductors. This would be very expensive, and the cables would need supports about every 10 feet.

A high voltage at low current allows the use of much smaller conductors. The only price you pay is that you must use special techniques for holding-off the high voltage (special insulation, minimum distances, etc.) But the cost of this is much cheaper than using 0000 gage wire.

So one thing is settled: Transferring a high voltage at low current is much more efficient than transferring a high current at low voltage. But should it be AC or DC?

Let's say a power station generates electricity and somehow boosts it up to 100,000 VDC (at 1 amp). Sure, the line losses are relatively low because of the low current, but how do you convert the 100,000 VDC to something you can use at your house or business, like 120 VDC (or 120 VAC, for that matter)? Answer: It ain't easy. There is no simple, reliable, and efficient way to do it! Resistor dividers (and linear regulators) are horribly inefficient. And switched-mode converters are complex, unreliable, and expensive. (Note that I glossed over the part of how the power company boosted the voltage to 100,000 VDC from the generators, but the same problem would apply there also.)

But with AC it's a different story. The power company can take whatever AC voltage & current is produced by their generators, easily & efficiently boost it to a higher voltage & lower current using a transformer, transmit the power over small conductors, and easily & efficiently reduce the voltage before it gets into your home with the use of another transformer.

Conclusion: High voltage is more efficient because insulation is cheaper than copper. But this requires boosting the voltage at the power station, and lowering the voltage at businesses and homes. AC is used because transformers can be used to do this job - there is no simple, reliable, and efficient way to boost/lower DC voltages.

[Engineer Don]

Good point, Crafter Man. That clearly shows why the majority if not all of any power distribution system would be AC. Since both ends of the DC transmission lines are AC, the transformers are located before the rectifier, and after the inverter, where the power is AC. Roughly the same size transformers are needed in either AC or DC transmission lines, so it wasn't a big factor in determining cost effectiveness. Technology related to power electronics, i.e. low loss rectifiers and inverters is what really made the DC lines possible. It wouldn't work at all on a totally DC system, though.

[stuyguy]

HELLLLLLLOOOOOOO...!!!!

When you guys are through talking about Edison vs. Tesla, and electric chairs, and power lines, SOMEBODY really should go back to the OP and try to give J-man an answer to his question. The poor guy has sat quietly by as everybody hijacked his thread without really addressing his Q.

How about it?

[LouisB]

Well, I got so wrapped up in rambling about Edison's estate that I forgot what I intended to say.

The lightbulbs I mentioned that were supposedly made in the lab at Fort Myers did have a metal base and they did screw into a ceramic socket.

I believe that the original, first bulbs were simply pinched off glass tubes or bottles, with a filament inside--basically the same technique used to build early prototype radio tubes. The wires required to operate them simply exited the bottom of the device and were hard wired to the power source. Of course, a vacuum was drawn on the tube before the bottom was pinched off. I am almost positive that my father recited all this from a "tour leaders guide" of some sort. I wish I could be absolutely positive.

He is now ninety years old and hasn't done the tour thing for a lot of years. His memory comes and goes but I will try to ask. Note the "try," my memory comes and goes, too.

[Crafter_Man]

Thanks Engineer Don.

I'm still unclear why a very high voltage DC transmission line would be more efficient than a pure AC system. So I'm trying to figure it out…

Correct me if I'm wrong, but I don't believe AC has any advantage over DC when it comes to I^2R losses (heat losses). 1 amp of DC current produces the same heat loss as 1 amp RMS of AC current in a given conductor.

Now an AC system will exhibit a reactance loss which is not present on a DC system, but this will only be significant on very long runs for a 60 Hz system. I still couldn't imagine there would be much benefit for going DC, even if the runs were long…

You also mention that it was used "to connect two systems operating at different frequencies." Hmmm. Perhaps this is the primary reason? If power station "A" is sending electricity to power station "B", but "B" wants it at a different frequency, then I suppose you could do one of two things:

1. Power station "A" could send AC to "B", but "B" would have to rectify it to DC, then reconvert it to AC at whatever frequency it wants.
2. Power station "A" could rectify the AC to DC, send the electricity to "B" in DC, then "B" could reconvert it back to AC at whatever frequency it wants.

Two conversions take place in each of the above cases, so it's a wash. BUT, #2 would be a little more efficient because there are no reactance losses during the transmission. So is this why they do it?

Now let's assume station "A" is sending power to stations "B" and "C", and both want it at a different frequency that what "A" is supplying. Two options:

1. Power station "A" could send AC to "B" and "C". "B" would have to rectify it to DC, then reconvert it to AC. "C" would also have to rectify it to DC, then reconvert it to AC.
2. Power station "A" could rectify the AC to DC. "B" would have to convert it to AC. "C" would also have to convert it to AC.

So let's tally up the score… There are 4 conversions in scenario #1, while only 3 conversions in scenario #2! Not only that, but #2 doesn't have any reactance loss.

And the more power stations that "A" delivers to, the more efficient a DC system becomes. Assuming, of course, that each station wants it at a different frequency.

Is my reasoning correct? Or am I off-course?

If it's correct, then I have another question: Why would another power station want it at a different frequency?? I thought all systems in the U.S. ran on 60 Hz. Or would the customer be someone other than the U.S.??

[Guinastasia]

At the risk of sounding stupid, what the hell IS AC DC, in a simple, Electricity for Dummies explanation?

Also: Didn't Tesla wipe out a whole forest in Siberia doing a test once?

[Punoqllads]

Originally posted by Crafter_Man

I'm still unclear why a very high voltage DC transmission line would be more efficient than a pure AC system. So I'm trying to figure it out?

Correct me if I'm wrong, but I don't believe AC has any advantage over DC when it comes to I^2R losses (heat losses). 1 amp of DC current produces the same heat loss as 1 amp RMS of AC current in a given conductor.


My understanding is that an AC current can use transformers to step up its voltage while reducing its current, and that a DC current can not. As long as viniin = voutiout the total power remains the same, but the power loss, i2r falls quadratically. Then, close to the user, the voltage can be stepped down, raising the current inversely as before.

Why the same thing doesn't work for DC, I don't know. I can't think one up, and I can't find a reason in my searches of easily-accessable resources.

[carnivorousplant]

Originally posted by Guinastasia
At the risk of sounding stupid, what the hell IS AC DC, in a simple, Electricity for Dummies explanation?

Also: Didn't Tesla wipe out a whole forest in Siberia doing a test once?


DC = Dircet Current, a positive and negative, like a bettery.
AC=Alternating Current, it swirches from positive to negative to positve 60 times per second in US households. Generators (or alternators) produce AC.

[Crafter_Man]

Originally posted by Guinastasia:
"At the risk of sounding stupid, what the hell IS AC DC, in a simple, Electricity for Dummies explanation?"


AC stands for "alternating current," and is used to describe current that flows in both directions in a conductor (not at the same time, of course; the current alternates back-and-forth over time).

DC stands for "direct current," and is used to describe current that flows in one direction in a conductor.

Personally, I think the term "AC" shouldn't be used to describe what's going on at your ordinary 115 VAC outlet. I think it should be "AV" (alternating voltage).

Why?

The voltage at your outlet is ALWAYS alternating, no matter what the load. But the current can be AC, DC zero - pretty much anything - depending on the load. For example, half-wave rectification causes a pulsating DC current to flow in your power line. And what if there is no load at all? The voltage is still present (and is alternating), but the current is zero! (Yea, I know, there's a tiny bit of current due to line capacitance. But I'm trying to keep this simple.)

Wanna hear something else? Contrary to what I and others have said, it IS possible to use a transformer w/ DC, IF the DC is a pulsating signal. That's how the coil in an automobile works.

The confusion, of course, is that we envision a steady, non-changing signal when we think of "DC." But a pulsating/changing signal can also be defined as "DC" as long as the current is always traveling in the same direction.