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Comment He's totally wrong. (Score 1) 292

When Bill Gates says:

"There's no battery technology that's even close to allowing us to take all of our energy from renewables and be able to use battery storage in order to deal not only with the 24-hour cycle but also with long periods of time where it's cloudy and you don't have sun or you don't have wind."

he's totally wrong.

For starters, there's Vanadium Redox. A flow battery (pumped electrolyte): Power limited by the size of the reaction device's electrode and membrane assembly. Energy storage limited by the size of the tanks. It's mainly used for utility-level energy storage down under (Oz or Nz, I think), because the patents are still fresh and the little startup doesn't want to license it to others. Vanadium is some substantial percentage of the Earth's crust so there's no shortage. Using the same element (in different sets of oxidation states - vanadium has (at least) 6 of 'em) for BOTH electrodes means leakage of small amounts of the element through the dilectric membrane doesn't poison the battery.

Lithum cells are already good enough to run laptops, cars, and houses, and are improving at a Moore's Law like rate. The elements are also not rare and the use of several nanotech techniques on the electrodes have drastically increased the lifetime and other useful properties. (We just had reports of yet another breakthrough within the last day or so, doubling the capacity and extending the life.) The fast-charge/discharge cells are also extremely efficient. (They have to be, because every horsepower is 3/4 kW, so even a few percent of loss would translate to enormous heat in an automotive application.) The main problem is to get companies to "pull the trigger" on deploying them - and risk their new production line being rendered obsolete before the product hits the market by NEXT month's breakthroughs.

Lead-acids need to be replaced once or twice per decade. But they have been the workhorses for off-grid since Edison's and Nikola Tesla's days, and still are today (though not for long, if Elon Musk and the five billion dollars of investments in his lithium battery plant have anything to say about it).

Nickel-Iron wet cells are a technology developed by Edison. They have more loss than lead-acids. But they literally last for centuries. If you have a moderately steady renewable source (like some combination of enough wind and a big enough windmill, enough sun and a big enough solar array, or a stream and a big enough hydro system) you'll have enough more power than you need to keep them topped off. They're just fine for covering days, or even a couple weeks, of bad generation weather, or down-for-maintenance situations. That IS what they were in at least one hydro plant I know of. (The problem is finding them: They last so long you only need to buy them ONCE, so there aren't many plants.)

That's just four FAMILIES of entirely adequate solutions. There ARE more.

So Bill is either uninformed, talking through his hat, or starting on the "embrace" stage of yet another:
  - Embrace
  - Extend
  - Extinguish
  - PROFIT!

Comment Re:What an opportunity! (Score 2) 359

Bitcoin is not actually deflationary. Its supply grows constantly until it eventually stabilises. The fact that Bitcoin prices have fallen a lot is more because lots of new people have discovered the project and decided they want some, but that effect will eventually peter out as Bitcoin becomes boring and everyone finalises their opinions of it.

Greece doesn't need fiat currency. What Greece needs is hard money – like the Euro (which is hard-ish, though not as hard as Bitcoin). This is because the Greek government is notoriously corrupt and the fact that they couldn't just print the pensions of their civil servants was one of the few things creating pressure to reform, and preventing outright pillaging of the savings of Greeks who do actually work in the private sector. Seeing Greece as one monolithic entity isn't right: there are different factions, not all of whom want the government to suddenly be able to spend whatever it wants. Hence the Greek people apparently voting for both keeping the Euro and not enacting any spending cutbacks, a contradictory position.

Ultimately Greece is going to get a lot poorer, no matter what. In many ways it's practically a third world country, one that was simply kept afloat by huge injections of foreign cash. But it never really stopped being third world in the way that it was run.

Bitcoin could, theoretically, benefit some Greek people now in the heat of the crisis because the Greek government wouldn't be able to impose capital controls on it. Thus preventing the outright theft of whatever little cash Greek's have left in the bank (sorry, I mean, solidarity tax/haircut/pick euphemism of choice). It is no magical cure for Greece's problems but it could tip the balance away from a government that discovered it was paying salaries and pensions for entirely non-existent departments, and towards people who are just trying to make a living.

Comment Re:Ok Google, time to ditch Java (Score 1) 181

Lots of things can be considered an API. For instance, who owns the copyright on OpenGL? Does anyone even know? What about HTTP? After all, a protocol is basically an API that runs over wires instead of call stacks. And HTTP/2.0 is a derivative work of SPDY which is .... developed by Google. And is now being added back into Java. What about SQL? It's managed by ISO these days so probably Oracle would avoid slicing their own throats like this.

Following this US ruling all sorts of people and companies are now finding that they own IP they never even knew they had. This is already making lawyers the world over start licking their lips. It's going to be a shitstorm.

Comment Second law of thermodynamics. (Score 2) 292

we have a way to turn electricity directly into heat. But there is no direct way to turn heat into electricity. It has to go thru a second step of mechanical energy to spin a magnet to create electricity.

You can go from electricity directly to heat because that increases entropy. You can't go from heat to anything useful because that decreases entropy, and entropy of a closed system only increases. The best you can do is a heat engine, working off a temperature DIFFERENCE. (Some of them also work backward as heat pumps, to go from electricity to heat more effectively, by also grabbing some heat from elsewhere to include in the hot end output.)

There ARE at least two major forms of electronic heat engines - direct from temperature differences to electricity, with only charge carriers as the moving parts: Thermoelectrics (thermocouples, peltier junctions, and thermopiles of them) and thermionics (both heat-driven vacuum diode generators and a FET-like semiconductor analog of them). Both are discussed in other responses to the parent post.

Comment Thermionics (Score 3, Interesting) 292

TEs are ridiculously inefficient and aren't looking to be much better anytime soon

Because thermoelectric effect devices leak heat big time.

However there's also thermionics. The vacuum-tube version is currently inefficient - about as inefficient as slightly behind-the-curve solar cells - due to space charge accumulation discouraging current, but I've seen reports of a semiconductor close analog of it (as an FET is a semiconductor close analog of a vacuum triode) that IS efficient, encouraging the space charge to propagate through the drift region by doping tricks (that I don't recall offhand). The semiconductor version beats the problems that plague thermoelectrics because the only charge carriers crossing the temperature gradient are the ones doing so in an efficient manner, so the bulk of the thermal leakage is mechanical rather than electrical, and the drift region can be long enough to keep that fraction down.

Comment Re:Bullshit narrative ... (Score 1) 230

It's systematically ignoring laws and regulations while going "wah wah, we're teh underdogs".

Uber is not unregulated and they do not stand in opposition to regulations in general, contrary to what many seem to believe.

What we're witnessing here is not State Vs Anarchy Round One. What we're witnessing is quite simply State Regulation vs Corporate Regulation. The existential question Uber faces is, can they convince society and government (not the same thing) that they're better at regulating taxi drivers via their technology than local taxi commissions are via paperwork? Even if Uber triumphs, this will not mean widespread usage of unregulated taxis, it just means that taxi drivers will live in fear of getting low star ratings instead of having their local medallion revoked.

Comment Re: AirBNB is hurting Barcelona, badly. (Score 1) 104

Getting drunk and running amok is something you do when not home--at home you might exercise some moderation, or there'd be people who'd call you out on it whose authority you'd feel obligated to respect

I hate to say it, given that I'm British, but unfortunately the problem of a subset of Brits getting completely wasted and engaging in shitty, boorish behaviour isn't something restricted to holiday times. For some reason the UK just has a far more serious problem with drinking than other cultures and it happens at home as well. I normally don't go to the sort of European resort towns that the hooligan set like to frequent but on the occasions that I have done, it's always embarrassing as fuck to be a young male British tourist because you can sense the suspicion locals have that you might be about to do something stupid. The worst was when I visited Bratislava. Lovely city (well, town, by UK standards). The pub in the city centre had the phone number of the British embassy on the beer mats, for people to call in an emergency. The men's toilets had a poster warning Brits specifically not to hit on the local girls. When I was there, a group of Brits came in with some unbelievably grotesque, obese men being led by some extremely hot local girl. Very obviously a stag do. As one of the fattest guys walked past the table where me and my friend were sitting he said (very loudly) "I want to see some TITS".

I pretended to be Canadian. Luckily I don't have a strong British accent at all and I was travelling with an American, so it was somewhat plausible.

I think you're completely right that this behaviour is partly learned and transmitted, like some sort of mind virus. For some reason Brits seem far more likely than other people to feel they can't have fun or be socially relaxed until they've got drunk, and will happily admit it. It's not seen as something shameful, people just blurt it out, like saying it somehow makes them one of the group. Combine it with a culture that practically celebrates "laddishness" as being fundamental to being a man, and you've got a recipe for trouble.

Comment Then again. (Score 1) 62

I got the impression from the (sketchy) article that repeater AMPLIFIERS were still needed but repeater REGENERATORS were not.

Then again - another part of the article makes it look like an additional result was that they could boost this less-subject-to-degradation-by-nonlinear-distortions signal at the start until the fibre itself was acting non-linearly, in order to get a signal strong enough to survive a much longer hop.

So it's not clear to me whether the distance was achieved by:
  - long hops enabled by strong signals, and NO amplifiers
  - longer propagation without regenaration using JUST amplifers
  - a combination of the two: Both getting long total length without regeneration AND being able to use stronger signals and thus use larger space between the amplifier-type repeaters.

Comment but not amplifiers (Score 1) 62

Since the diameter of the earth is 7 926.3352 miles, this could conceivably remove any need for repeaters.

I got the impression from the (sketchy) article that repeater AMPLIFIERS were still needed but repeater REGENERATORS were not.

I.e. you still needed to boost the strength of the signal to make up for the losses. But the progressive degradation of the quality of the signal - with data from different frequency bands bleeding into other bands (especially in the amplifiers themselves) due to nonlinear "mixing" processes - had been headed off, by synchronizing the frequencies of all the carriers to exact multiples of a common basic difference-between-the-carriers frequency.

This apparently sets up a situation where the distortion products of each carrier's interaction with nonlinear processes cancel out with respect to trying to recover the signals on another carrier - much the way the modulation products do in OFDM modulation schemes. In OFDM it allows you to make essentially total use of the bandwidth. In this system it lets you use simple, cheap, amplifiers to get your signal boost, rather than ending the fibre before things get too intertwingled, demodulating all the signals back to data streams and recovered clocking, then generating a fresh set of modulated light streams for the next hop - MUCH more expensive and power hungry.

Comment Re:Randomness can't come from a computer program (Score 1) 64

Most of us do have a need to transmit messages privately. Do you not make any online purchases?

Yes, but those have to use public-key encryption. I am sure of my one-time-pad encryption because it's just exclusive-OR with the data, and I am sure that my diode noise is really random and there is no way for anyone else to predict or duplicate it. I can not extend the same degree of surety to public-key encryption. The software is complex, the math is hard to understand, and it all depends on the assumption that some algorithms are difficult to reverse - which might not be true.

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