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Comment Re:Why? (Score 3, Interesting) 321 321

I had the same question, honestly. But it might have some benefits...

A cargo ship has a top speed of under 25MPH (20 knots). A Class 5 freight train can hit 80 MPH and there's no *technical* reason why they couldn't go even faster. Even with the increase in distance by taking the long way around, you can maybe reduce transit time. Such trains could also load and unload deep inland, closer to where the cargo is needed, eliminating multiple handling steps.

I still don't think it's a *good* idea, but it's slightly less crazy than it might initially sound.

Comment Re:Why not both? (Score 1) 237 237

Offer void where constant-speed is not the most efficient. Pumps and fans that can match the actual demand by varying speed will be more efficient than running a full out and bypassing or artificially increasing head pressure to get the desired flow.

You're also not going to put an across-the-line starter on a motor larger than about 50HP unless you like replacing equipment. You'll always have a soft starter to get things going - this is doubly important if you're starting the motor under load.

Comment Re:Why not both? (Score 1) 237 237

So called Brushless DC motors are actually permanent magnet rotor, synchronous AC motors?

They are virtually identical, yes. There might be some nuanced differences in their physical construction or drive (sinusoidal vs trapezoidal waveform, for example) but the operational principle is the same.

For fractional horsepower motors there's no cost-benefit to doing sophisticated controls in most cases. You just need it to turn on and off at one, sometimes two or three speeds and the load is more or less constant. I wouldn't expect that to change any time soon.

Comment Re:Efficiency (Score 1) 871 871

Flywheels can be charged up lots faster than batteries.

That depends entirely on the design of the flywheel/battery. But you know what flywheels do better than batteries? Leak. An idle flywheel will lose energy much faster than an idle battery.

Supercapacitors are neat but have the worst volumetric energy efficiency of then all.

Comment Re:Efficiency (Score 1) 871 871

But for the cost and weight, a battery is better than a flywheel in essentially every aspect. For however much you reduce the required size of a flywheel, you can reduce the battery size as well.

Battery systems are damn close to 100% efficient if you're not too close to fully charged or fully discharged, or not diving the current much higher than 1.0C.

There is no advantage to using a flywheel at all. None.

Comment Re:Easy Conclusion If Perceived Costs & Range (Score 1) 871 871

In 2013, the average price for a new car was $32K. Many EVs available right now are below that even *before* any state or federal incentives, and many more hit that point after incentives.

Meanwhile, the average price for a used car was $16.8K. I don't know where you'd get a sub-$10K used vehicle from a reputable source (versus a cash transaction in someone's driveway...)

Comment Re:Efficiency (Score 1) 871 871

Consider replacing the electric commuter-car battery with a flywheel. We have the tech to do this for ranges of 50 miles or so.

Why would you, though? Flywheels have atrocious energy densities.

We should be thinking about replacing batteries with "fuel cells", because, like hydrocarbon engines, only fuel (most agree hydrogen is best) needs to be carried around, and the waste (H2O) can be dumped.

Wrong. A fuel cell car also needs a sizable battery, because a fuel cell capable of providing sufficient output for acceptable performance would be massive and expensive. A battery needs to be included to provide the peak power and the fuel cell basically acts as an on board generator to keep it topped off.

And given that, it's a waste. For all the solar energy you collected to make and process the hydrogen, you could have put that directly into an EV's battery and come out way ahead.

Comment Re:Why not both? (Score 1) 237 237

if you're going to have an internal module that "generates whatever voltages are needed" then you're just going through the conversions again, and you're saving nothing on efficiency (and losing a lot on costs).

The only way it'll work is if the DC input, eg solar panels, is matched to the unit's requirements. Anything other than that and you're just running in circles.

Comment Re:Solar Powered Aircon (Score 1) 237 237

Of course you can power everything with heat. Indeed, nearly everything *is* powered with heat; Most conventional power plants use thermal processes, converting heat energy into mechanical energy then into electrical energy.

A solar powered refrigerator (or any refrigeration cycle driven directly by heat) allows the use of fairly low quality heat sources to do useful work without losses converting it to electricity first. Very useful in some circumstances.

Comment Re:Why not both? (Score 3, Informative) 237 237

And yet, in practice, HVDC is still more efficient than current AC lines in the end, even if still somewhat more expensive at the moment.

Yes and no.

AC power is far more efficient at higher voltage and short to medium distances, and you save a lot of material (and thus money) on conductor sizes. The voltage can be changed easily and it is safer and easier to switch on and off since there's 50 or 60 times per second where the voltage/current is zero - allowing for the circuit to be opened without arcing or inductive voltage spikes. AC arcs also tend to be self-extinguishing for this reason.

But AC systems also have inductance and capacitance to deal with. For very high power, very long distance runs, the capacitive losses start to add up. More current is required to charge/discharge this inherent capacitance, which means more power losses. This is where HVDC really shines.

Comment Re:Pay us or the suit gets it! (Score 2) 106 106

having said that, WHY isnt there a breakdown, line item, for all costs that our government spends?

There is, but you're clearly too lazy to look for it and almost certainly too lazy to actually read through it.

That took all of 5 seconds on Google. That's FY2013 but it's hard to imagine anything significant changed for FY2014.

Reports similar to this are available for just about every government agency. The budget omnibus that congress passes is a matter of public record as is the requests that each government agency submits (which the budget omnibus is based on).

Of course they aren't going to just mail these reports to you on a subscription basis - you actually have to get off your ass and find them or... god forbid... ask for them!

Comment Re:Rubbish (Score 4, Interesting) 159 159

Fake acupuncture, where the skin isn't penetrated at all, was found to be much more effective than real penetrative acupuncture and acupuncture improperly applied (needles in the "wrong" locations).

And the tests were done on human volunteers. Citations in the video description.

All syllogisms have three parts, therefore this is not a syllogism.