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Comment Re:Trucking (Score 1) 716 716

I also have though through the battery swapping thing and have concluded that it is problematic and would just be a workaround solution...much better for cars to not need to swap.

But you bring up a good point about trucks. That might make sense, although I'm not sure having it an integral part of the trailer makes sense because the load might need to keep moving even if the batteries are not. But battery swaps seem to make more sense where there are limited, repeatable, planned routes. That applies to city buses and similar. For general cars, it just seems like we'd need to many batteries moving around, a waste in its own sense.

Comment Re:DC power? (Score 1) 212 212

How are line losses minimized for DC over AC, given the same "RMS" voltage (yes, I know the term means nothing in DC) and Current?

In the simplest terms, DC current losses are only result from the line resistance. AC losses are due to the line resistance plus reactive losses. Reactive losses are basically the capacitive and inductive losses that result from the constantly changing current and voltage. Various factors are at play, but you wind up with the voltage and current sine wave getting out of sync with each other. If that doesn't seem intuitive, imagine something at work trying to bring those two back into synchronization... that would be the reactive losses.

The higher the voltage, the less line resistance becomes a factor, but that does not apply equally to reactive losses.

Comment Re:Trucking (Score 1) 716 716

Electric cars will be better than any alternative, including the loud, inconvenient, gas-powered jalopy,"

Lets look at this in the frame of the next few years. As of now, pure EV's have their own inconveniences and restrictions. HEVs less so, but they are not much quieter than many quality ICE cars. In fact, tire and wind noise become significant in either case. As for "jalopy", well, a very subjective term that could be applied to any old vehicle, be it gas or electric. There are some very nice ICE cars that would be hard to see as being described as a jalopy any time soon.

He may be right, he may be hopeful, but he's not apparently that objective.

Comment Re:Would I eat it? (Score 1) 128 128

Your whole summary is quite telling. You say you use scientific methods to evaluate risk, yet you repetitively ignore probability. Probability is central to scientific evaluation of risk.

And you demonstrate your ignorance to the actual risk by comparing eating this screened food to racing cars and bungee jumping. The risks of the latter are many orders of magnitude greater.

You can go on and on about bio-accumulation and generally state that it is going to result in all these horrible outcomes, but reality shows that those outcomes will almost certainly not occur from ingesting such small amounts. Interesting you talk of the body's ability to heal in a car crash but not the human bodies ability to remain healthy despite the biological interactions that your fear. And you do not always heal from injury, rather many injuries increase risk of stroke from clotting for example, ro debilitating nerve damage... it is quite entertaining to me to see you blow that off.

If you applied your same logic regarding zero exposure to radionuclides to other things our do, you would certainly avoid any unneeded exposure to sunlight/UV, because you, as you accuse me, must be stupid and ignorant to allow any at all to hit your skin because of the horrible outcomes that might occur, I can see the cancer growing in my mind! Do complain to me when that happens.

I think you would be surprised to find out about all the potentially harmful chemical and contaminants you eat from out normal food supply chains, and how those risks compare with eating this screened food from Fukushima.

And to top it off, you seem to think that you are so objective that you are not subject to skewed risk perception influencing your decisions. But you are fooling yourself because we all are subject to it, and those that are most likely to be skewed significantly by it are those that don't understand just how susceptible they are.

With that, I'll let you follow with another poor example, using some activity which is much much riskier, I'll let you follow with a strawman that completely avoids discussion of probabilities, and I'll let you go on thinking that you are not taking any unnecessary risks in your life that are many times greater than eating the food of topic. I'll you you go on believing your own little facade that your absolute zero exposure philosophy is being equally applied throughout your decisions in life.

You have clearly answered all my questions.

Comment Re:Why not both? (Score 1) 212 212

Your points are valid, I'll just add that we are not really even talking about a high level of complexity either way. These power/control approaches are nothing new, they are used and proven and quite simple and reliable, they are just being adapted to this application. In some ways having DC input really makes motor control easier and you don't have to deal with current/voltage frequency to begin with, and digital controllers are so easy to implement.

Comment Re:What Voltage? (Score 1) 212 212

There's no connection between ground faults and bad connections that might cause overheating.

I understand that and did not mean to imply there were. I suppose my wording could have been better. Just meant to point out some specific inherent differences that relate to safety.

Comment Re:Would I eat it? (Score 1) 128 128

You are full of straw, man.

You certainly avoided my question quite intently. So let me ask again; Do you ever take an unnecessary car ride?

We both know why you are avoiding an answer. Because the answer is YES and in completely undermines your insistence that your choices are based on science and understanding.

To answer both your questions, would I eat food from Fukushima with a defined amount of contamination, the answer is YES, if that level was measured to be below the safety thresholds set by Japan using the methods they established. So, YES, I would do so with no worries.

Do you take unnecessary car rides?

Comment Re:What Voltage? (Score 1) 212 212

> Higher voltage would work better, but call into question safety issues you don't have with AC due to it passing through zero volts 100-120 times a second.

AC running from hand to hand will likely kill you, causing your heart to try beating to it.

So will DC. And at a given voltage, DC is worse as the current is constant and doesn't like to be interrupted.

Comment Re:What Voltage? (Score 1) 212 212

Noticeably missing from both linked TFAs. As discussed here and elsewhere previously, 48V would probably have too much ohmic loss unless this A/C is right next to the supply. Higher voltage would work better, but call into question safety issues you don't have with AC due to it passing through zero volts 100-120 times a second.

I'm not sure the resistance losses would be that significant as to be an issue. The safety question is a good one. 48V home DC systems are common enough and I believe they are well covered by code, so installations done right should be safe. DC can be problematic in that you can't always detect certain faults as there is not ground fault current, so there is inherently some greater chance of something like a bad connection overheating and causing damage, but that should not really be a concern if stuff is quality and installed correctly.

Comment Re:DC power? (Score 3, Informative) 212 212

High Voltage DC transmission makes sense in some applications. Its best as a single point to point solution over a fairly long distance, as line losses are minimized. High voltage DC switching and DC to AC conversion equipment is very expensive compared to AC, and typically has a shorter lifecycle, so you don't really want to have a lot of DC switchyards.

Comment Re:"...the same as trespassing." (Score 1) 1130 1130

Again, it has nothing to do with my point, which was harming an object vs harming a person, which was central to the OPs point. The OPs point had nothing to do with where the gun was fired, or peripheral damage, neither did mine.

If it makes you feel better, I also recommend not shooting a gun indoors. But I think most folks already know that.

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