Has Thomas Edison ultimately won the DC vs AC power transmission controversy against Tesla?

1/7/2013 2:40 PM EST

First , I wanted to ask if this article was reserved for April Foos Day. Second , it looks like all my physics and advances circuits professors were idiots. The third - heart is a "motor" of our body. It works on quite complicated principle of electrical pulses. I would like to explain something without going too deep into a subject. Positive pulse causes the heart to contract (and stay as long as pulse lasts) Negative pulse relaxes heart muscle. Therefore for those who still believe in idiotic Edison experiment with an elephant - it is NOT AC that kills easy, but DC. They just killed an elephant by burning it! DC causes heart muscle contraction and often leads to sudden death. AC will cause heart flutter and also lead to complications, byt rarely death. Most animals can be killed with a trivial 48VDC and lower. Another thing is a destruction from an electrical line contact. It can damage a lot, but DC always does it irreversibly. No smallest doubt about it.

1/7/2013 2:42 PM EST

Sorry , I meant April Fools Day and advanced circuits professors.Sorry for mistakes.

1/8/2013 3:01 PM EST

Why the incessant need to constantly try and undermine Nikola Tesla? Even if, as the article suggests, modern technology supports the reemergence of DC, then how can that be attributed to Edison? Bottom line, in their respective co-existence, both subject to the technology of their time, as well as their own intellect and ingenuity, Tesla out-engineered Thomas Edison. End of story.

1/8/2013 3:14 PM EST

I would also like to see Edison get away with buying cats and dogs for a quarter and then publicly electrocuting them. Aside from the fact he is dead, of course.

I am not qualified to judge the veracity of the claims - I only play EE on TV, but I found the article to be an advert for ABBA.

One of my questions is: given that the footprint of the towers are roughly 2:1 (AC needs 2 towers to every 1 for DC, according to the pictures), can the existing transmission lines be switched over without changing the middle? (obviously the ends would need to change.)

Tesla was a true genius. Edison was a businessman who hired bright folks. Tesla had more inventiveness in his pinky than Edison in his head. Both had their place, but Tesla is a better hero.

1/8/2013 3:17 PM EST

Blatant assertions without numbers fly in the face of reality, albeit satisfying to some. Neither IR losses are presented numerically, nor is the efficiency of the DC to AC and AC to DC conversion so brazenly presented in order to make a distributable product.
No numbers, no facts, no sense, or, rather, nonsense.
A little learning is a dangerous thing
Drink deep of the Pyrian Spring.
We live in a world of dumbed down folks, one product of which is this bit of advertising propaganda for a Swiss switch (in itself ridiculous).

1/8/2013 4:13 PM EST

High voltage DC transmission lines are definitely the future for power distribution systems - several of these transmission lines are already in use in Eurasia and several areas of Northern Europe. Power distribution in our hybrid-electric combat vehicles utilize a HVDC link for power distribution; various conversion modules take care of sourcing different levels of DC voltages and/or AC voltages as requirements dictate - these converters are all efficient in the ranges from ~94% to 97%.

As far as Edison's approach to try and prove AC more dangerous than DC, that was extremely unfortunate and wrong-headed. Death from either DC or AC is still death and if a current path is found through one's heart, all bets are off! By the way, the SAE specifies a safe DC voltage level of 48VDC maximum.

1/8/2013 4:31 PM EST

Definitely a PR puff piece for the technically semi-literate, and not reasonable for this audience. EDN must be hurting for content.

1/8/2013 5:51 PM EST

Was Edison better? Was Tesla better? This kind of question is bunk - it verges on religious argument. Look at the technology of the time, and which system was used to implement the power grid.

Can we build a technically superior power grid, lo, these 100+ years later? Yeah. Give Edison points for trying it out back when - even major failures provide valuable lessons. They point out what has to be invented.

Edison told George Westinghouse's son, after George's demise, "Tell your father I was wrong." Nice sportsmanship, eh?

So, does the increasing viability of HVDC distribution invalidate Tesla's achievements? Tesla's main fault was his near-total lack of business acumen. If he had become insanely rich, would everyone think better of him?

If so, I think there are questions we should be asking ourselves about what we really value.

1/8/2013 6:07 PM EST

who of you folks has practical experience with DC power distribution system? Unfortunately in my childhood until 1952 we had 220DC, I could tell you, DC shock is much worse than AC for the same voltage, and all light switches, connectors [power outlet] plugs have a very limited life time, DC arc burns everything.

1/8/2013 7:07 PM EST

i have an old map of the u.s. grid showing every major line and power station functioning in 1974. it shows a HVDC link from the columbia river to los angeles. one would be left wondering how it is protected without ABB's super fast "miracle disconnect" ? as of a few years ago i witnessed its operation : at least 30+ years. not bad for pre 1970 technology.

1/8/2013 7:46 PM EST

Several things are clear: For long distance power transmission lines, DC is more efficient. No question about that. BUT when we get to the end of the line and need the voltage stepped down to make our LED lighting system work, That is a different sort of challenge. Distribution of power throughout the neighborhoods presently uses a lot of transformers, so that the feeds can be higher voltage at lower current.
The challenge, now as back in Edison's time, is voltage changing. DC transformers still need a few active parts, they are still more expensive and less reliable, and they take up more room.
So the final conclusion, for now at least, is that each mode has it's application, and the applications are not the same.
And the explanation in the video left a whole lot of question unanswered, at least, it didn't answer many of my questions. It would be adequate for a liberal in government, but not for any engineer. Could we have an actual explanation, please?

1/10/2013 1:40 PM EST

This whole "Battle of the Currents" thing is silly (stupid) to begin with. No one is going to fix a Swiss watch with an air wrench. Likewise, you're not going to change the tire on a semi with jeweler's screwdrivers. Use the right flippin' tool for the job. Connecting grids with HVDC sounds like a good use of that tool. Local distribution using DC sounds foolhardy. What's wrong with letting the economics of the situation dictate the tool? The BPA has been using HVDC links for decades. It makes good cents. I believe we may be building an argument for creating a nationwide HVDC "Interstate Highway" system for distribution of power. Sharing capacity sounds like a good idea. The other thing is are your lives so vacuous that you actually expend effort on defending whether Edison or Tesla had a larger p----, I mean intellect? Get a life.

1/14/2013 8:32 PM EST

I'd like to see the efficiency factors for converting from AC to DC and then back again for a multiple-100 kV transmission line. And then I'd like to see the reliability and longevity of the equipment required to do this. Also, why is a transmission line more efficient for DC than for 60 Hz AC? It may be, but it's not explained.

This whole idea seems ridiculously impractical and unlikely.