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Comment Re:Even if you go DC, stay at 120V (Score 4, Interesting) 597

(Continuing after brushing the touchpad posted it for me. B-b) ... equipment at that voltage. (Small systems are often 12V due to the availability of 12V appliances.)

But back to inverters:

Current inverter and switching regulator (they're pretty much the same stuff) technology is SO efficient that large PC boards in computing and networking equipment may run the power through as many as THREE DC-DC converters, because you lose less power to heat as losses in the inverters than you would to resistance running it a few inches through a printed circuit board power plane.

So the '"20-40% loss" number seems to me to be utterly bogus.

(Consider this: A Tesla automobile IS AC motors driven by inverters from batteries. A horsepower is almost exactly 750 watts. If they had 20-40% losses in the inverters, how do you keep the car from being on fire after a jackrabbit start? Let alone recover enough power on braking to reuse on acceleration to make a substantial difference?) If ANYBODY knows how to handle inverters it's Tesla. B-) )

Comment Even if you go DC, stay at 120V (Score 4, Interesting) 597

This is strange. "20 to 40% power loss" seems to be an awfully poor inverter; existing inverters are 4-8 % loss.

Rather than rewire every house in America, wouldn't it make more sense to just design better inverters?

Or just run at 120V DC, as renewable energy systems did (and occasionally still do) before so many appliances were AC-only that it made sense to use an inverter.

Dropping voltage means you have to replace the copper wiring with MUCH HEAVIER wiring - by a square law - to carry a given amount of power with the same loss - and thus wiring heating inside the walls, where it can set the house of fire.

Switching to 120V just means using DC-capable appliances and replacing the breakers (DC is harder to interrupt) and must-be-GFCI outlets (normal GFCI devices use a transformer to sense unbalanced load).

The 48V standard was about having a voltage that was low enough that touching it was typically survivable, so working on or near it is (relatively) safe. The boundary between the hard part and the easy, "low-voltage", part of the electrical code is 50V (BECAUSE of phone companies B-) ). Medium power (>1KW) home Renewable Energy systems tend to be at 48V so much of the wiring falls under the easier part of the code, and because of the availability of

Comment Re:Tesla enables Edison to win the endgame? (Score 4, Informative) 597

HVDC works well for long trunk lines between a distant large power source and a population center, but it much less useful for a grid system with many interconnect points. That's why the primary usage has been between hydro plants and distant cities and for international interconnects (especially where the local grids of the two sides do not share a common standard).

Comment Re:next up: ban cars (Score 2) 141

Well, driving cars in urban centers generally sucks between the traffic and finding parking. The problem is people are too stubborn to get their act together and provide abundant satellite parking and transit links. Sure, driving your car right up to a store is ideal when you're the only one doing it, but there's a reason malls are built with parking on the periphery and pedestrian access at the core. If parking was the most pleasant and convenient way to get a lot of people into a confined area you'd be able to drive right into Disney World and park your car at Space Mountain.

Comment Re:nonsense (Score 4, Insightful) 141

Anything that happens inflates someone's bank account. If governments ban CFCs then people with CFC substitutes get a windfall. If governments don't ban CFCs then makers of sunscreen and skin cancer treatments get a windfall.

This is how capitalism works -- how it's supposed to work. Problems attract capital, which generates profits. But it's also how market solutions fall short. It's better for the public if someone makes a killing replacing CFC than if someone else makes a killing treating skin cancer.

Comment Misses the strategic imperative for Android. (Score 1) 344

Google's core businesses would be seriously damaged if Apple obtained a monopoly on mobile computing. If it breaks even and prevents Apple hegemony it's as much of a success as it needs to be.

As for the supposed switching of Android users to iPhone, notice the tortured stipulations in this sentence: "the 'majority' of those who switched to iPhone had owned a smartphone running Android." It's also no doubt true that the majority of users who switched to new Android phone had owned a smartphone running Android in the past. The vast majority of smartphones out there are Android, and that's been true for years now, so it's not surprising that someone buying a new smartphone of any kind has previously owned *some* android handset.

Comment Not if they think they can get more work out of us (Score 1) 140

If this works, the monied and in-power will make this as illegal as LSD and heroin.

Not necessarily.

If the anti-aging drug(s) make people healthier, reducing the drain on the government pensions and enabling the government to push the retirement age out over the horizon, so the people will be working and taxed, they might prefer to have the drugs put into use.

Heck, they'd probably add them to the water.

Comment Re:Disappointing (Score 2) 105

LOL, more like it's audio for people who care about the quality of audio. I use the DTS HD-MA or TrueHD track with my receiver in pure direct mode so that I don't get all sorts of crap filtering and can just listen to the audio as it was intended to be presented (and how you'd hear it if you saw the movie in a theater, though generally with fewer tracks)

Comment Re:Go for it (Score 1) 43

I agree he doesn't belong on that list. I do think on the list of America's worst presidents, he'd be at the top of the list.

Ignored warnings from the previous administration, top FBI officials ignored field agents who were warning of something bad, and got our country attacked.

Then he started an incredibly stupid war in Iraq, which led to the rise of ISIS.

Presided over the building of mass surveillance of the American people.

Took office during a boom, left office under the worst economy since the great depression. It's my theory that what caused the ruined economy was fuel prices more than quadrupling during his reign. Buy gas to get to work, or pay the mortgage? Tough choice!

Took office with a balanced budget, left it with the largest deficit in American history. Meanwhile, infrastructure was crumbling and he did nothing.

Now, if the list was of people who did the most harm to our country, he should be on that list. Mao and Pol Pot were very evil men who killed millions of people, but they didn't harm America.

Comment Re:It only increases accountability (Score 4, Interesting) 294

Well, speaking of Amtrak employee accountability, I have a story about that. A few years ago my family took a train ride across the country. When we changed trains in Chicago I noticed that the reading light in my sleeping compartment was stuck on, which of course was bad if I wanted to actually sleep. I found the friendly and helpful attendant and reported it, and her reaction was like watching a balloon deflate.

"What's wrong?" I asked.

"If we report damage they take it out of our wages," she said.

"What! What do you mean take it out of your wages?" I asked.

"If a car is damaged under my watch I have to pay for it," she said.

"Well," I said, taking out my swiss army knife, "I guess there's nothing to see here."

I have to say that I've never encountered such a nice, enthusiastic, friendly group of people with such an abysmally low morale as the crew of a cross-country train. With passengers they're great, but all through the trip I'd see two or three congregated having low muttered conversations. It didn't take me long to figure out they were talking about management. And while the experience was wonderful, the equipment was in horrible shape. It was like traveling in a third world country.

With management that bad, more data doesn't equal more accountability and better performance. It means scapegoating.

Comment Re:30 years ago.... (Score 3, Insightful) 294

You are aware that plenty of people are monitored for their entire shift in much less safety critical jobs, like bank tellers, grocery or retail store cashiers, dock workers, etc, yes? As to the speed being controlled by computer, they've been working on that for some time, but apparently the radio network to convey all the necessary information to the control box is massively behind schedule.

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