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Comment Re:Wow (Score 5, Informative) 309

So when the economics make sense, investments follow, without the need for governments to step in and choose winners and losers. Who'd have guessed?

That's true. But it's ALSO true that government subsidies can accelerate the development of practical cost-effective technologies, by getting them scaled up earlier.

Comment Re:How would they know the order? (Score 4, Insightful) 99

They'd have to be watching them physically to know the order. This is bullshit.

4 digits: 10,000 possible combinations. Know the 4? 24 possible orders, in the worst case with no repeated digits. You really don't think that's important, huh?

And that's assuming that the thermal imaging gives no clues about order, which I suspect is actually not true...

Comment Re:This is good. (Score 1) 60

Tesla owner here: Your math is way off -

Indeed. Brain fart. Seem to have confused instantaneous power with stored energy somehow without factoring in time. D'oh.

So for 1-2 minute charging, would require 10x what I claimed. Now we're beyond smallish office building, but I suspect still well within the kind of power delivered to a shopping mall--although I'm not sure about that.

Comment Re:This is good. (Score 1) 60

And that 85khw represents perhaps only about a fifth of the work that you can get out of a full tank of gasoline.

That 85kWh gives the car a range of over 200 miles. What car gets > 1,000 miles on a tank of gas. I suspect you're confusing the total stored energy in a tank of gas with the fraction that an IC engine can actually convert to mechanical work.

I remember working it out once that if you wanted to fully recharge a hypothetical car battery in about the same amount of time it took to fill up a car with gas, and you wanted the battery to be able to move a 1000kg car as far as about a full tank of gas would go at the same speeds, to fully recharge in that short a time span would require a power output on the order of no less than 10 megawatts.

10 megawatts for 1 minute is 167 kWh, twice the capacity of a Tesla, so high, but within range. 4.5kA

Funny. My math was off; I was 10x low. Your math was off. You were at least 2x high, 4x if you go by my criteria of "filling up" in 2 minutes. Off to remedial math class for both of us.

Comment Re:This is good. (Score 2) 60

...you still couldn't draw enough power from the grid to get enough energy to saturate the battery in that time.

Indeed, it's a substantial power draw required to charge a car in a minute or two. Gas pumps can put out about 10gal/min, so 2 minutes is a reasonable max time to use for comparison purposes. To get a Tesla's 85kWh in 2 minutes from 230-volt 2-phase, that would be about 400A, which is twice the power supply to a typical house. (And of course that 85kWh does not get you as far as the 20gal of gas would; but still I don't think consumers will be doing those calculations; what they'll be doing is driving away reasonably happy if the "fill up" takes a minute or two, but annoyed if it takes 10-15, and if it takes 30, that's a huge limit on acceptance of electric vehicles. Also, there's the economic model for the business, having cars drive up, spend a minute or two and pay, then drive away is a viable business. Having cars take 10-15 is not; too much land and too many stations required.)

So the "gas station" of the future, despite being an itty-bitty building, would probably need electric service similar to a smallish office building. Way more than they have now, but certainly doable, certainly power at a level that is pretty common for commercial developments. (And, BTW, they certainly wouldn't deliver 230V @ 400A, that would be a copper cable that would resemble current gas hoses in diameter, too heavy and stiff to be practical. I'd think they'd have to bring 2.5kV, or maybe even 25kV down to the building and out to the charging stations.)

But right now none of that matters, because batteries can't take charge fast enough. The current (haha) bottleneck in charging speed is batteries, if that limit is lifted significantly, then it would on to the next bottleneck. (Or, ideally, things get planned well enough to evolve roughly together...) And of course big batteries at the "gas station" have all sorts of potential uses as well: smoothing demand by loading up ahead of peak business, loading up at off-peak rates, storing the output of on-site solar, cheating and draining the batteries of cars when they hook up (OK, maybe that last one is not a sustainable business model)

Comment Re:As much or more than the developer (Score 1) 350

It's a rare developer indeed that makes software that works well with less RAM than they have.

What an idiotic argument! Debuggers take memory. Profiling takes memory. Testing for access of previously-freed blocks takes a metric crap load of memory over and above what running the program normally would. And that doesn't even count that it's likely that we're running a database server and application back-end server in addition to the client software. Some days I'm running multiple versions of the back-ends...

Comment it's just not that great (Score 1) 231

Performance of my system went to hell when Apple added this to OS X. Apparently I was already on the cusp of needing more RAM, and this pushed me over the edge. The fundamental problem with this is that the compressed pages take up space in RAM when your system is already low on RAM. Duh. I think it's more about reducing writes to SSD than it is about improving performance.

Oh, so there you are!

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