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Comment That's NOT the real question. (Score 5, Insightful) 298

The "real question" is not whether net metering is good or bad. Of course it's good, and it will continue to become more common as solar (and even wind) micro-generation technology improves. It will get an even bigger boost if EV technology with bidirectional charging and large storage batteries become more popular, as Tesla would like them to. The dispute here isn't over net metering itself. The issue is all about the MONEY of net metering. Who pays what, and how? Before net metering, utility rates were set based on a fixed connection fee to pay for certain fixed infrastructure costs, plus an energy charge per kWh to gover generation costs. For large commercial users, the fixed fee was set as a "demand charge" based on peak consumption (since that determines how hefty the grid needs to be to serve the customer). For residential users, the demand charge is usually just a flat fee per month for the connection. In practice the demand/connection fee is not enough to actually cover the fixed costs of the system, and a lot of that expense is rolled into the energy rates. That doesn't matter in a world without net metering - it makes no difference to the utility whether they get their money per kWh or per month, as long as they get the money. Net metering screws this all up. A net-metered user may have zero net consumption in a month, while still requiring the same infrastructure as a user without net metering. As a result, the demand or connection charge needs to be greatly increased to make up for the lost kWh revenue.

The problem is that the adjustment of rates to accommodate net metering has been a hugely political process with every party trying to screw everyone else to the max. Solar companies want their customers to see huge financial benefits to justify their prices, so they lobby for net metering rates that strongly favor their customers: low monthly charges (ideally the same as for non-net-metered customers), with reimbursement for net metered power at the full retail rate (i.e. 1kWh sold back to the power company nets you the same money you would pay to buy the 1kWh from the power company). This makes solar look like a great investment. The problem is that is really does screw the power company. Since utilities are typically government-controlled monopolies, that means it actually screws the non-solar customers who will all be forced to pay for the net-meter-users' share of infrastructure. Not quite fair. On the other hand, though, we have utility companies trying to get the solar power as cheaply as possible while still collecting full reimbursement for infrastructure costs. They want to treat net-metered customers like power plants: charge them for all the infrastructure costs, and only buy their power at "wholesale" rates that are far less than what the consumer pays for power going the other direction on the same wires. This is also not fair, and screws the people who want to invest in solar by artificially depressing the value of their power. The solution must lie somewhere in-between. Utility rates and their basic method of allocating them will need to change, and it will take honest politicians not bought off by solar companies or utilities to reach a compromise that is fair for everyone. Fat chance of that happening any time soon.

Comment Nozels for printing metel, or just plasstec? (Score 4, Funny) 49

The nozel-based printors may be cool new technolligy, but can they print metel with a nozel yet? So far I have only seene plasstec printid via nozel, and metels can only be printid using laisre cintering. It would be a maijer advance in rapped prototaiping if metel objicts could be fabrecaited with an extruzhen-like addetive prawsess. You know, like with a nozel. Whew. That was hard to write.

Comment TSP (Score 4, Interesting) 481

Adding a few spoonfuls of trisodium phosphate to your dishwasher is hack #1. Most consumer-grade detergents these days no longer contain phosphates, since they act as fertilizers and promote algae growth when everyone disposes of large quantities in wastewater. Unfortunately, the missing phosphates have not been replaced with anything as effective at cleaning your dishes. Trisodium phosphate (TSP) is sold in powdered form in the paint section of hardware stores, because it is used for surface preparation. It's cheap. Don't get the "TSP Substitute" - it's not effective, just like the weak new detergents these days. Toss a couple teaspoons of real TSP in with your detergent for truly clean dishes, if you're not too concerned about the plague of algae growth. It works extremely well.

Comment Awful lot of money for some big flaws... (Score 5, Informative) 37

This is a pretty cool concept and a good start, but like consumer 3D printers from five years ago, it is not really practical or cost effective. The biggest problem this thing has is the $2199 price tag. Holy crap! Anybody can already make better quality circuit boards using a cheap laser printer, a blacklight, and some basic supplies. You could even build a DLP projector-based photolithography setup with great resolution for half that price, and people have done so. It just doesn't cost anywhere near $2199 to make good circuit boards.

That brings us to the next big problem: this thing doesn't make good circuit boards. Conductive ink is not a real substitute for solid copper traces. The traditional etched-foil method ensures uniform and predictable trace properties, and the solid copper has great current carrying capacity and low resistance. That matters a lot in many applications. Good luck handling tens of amps (or even more) in a switching power supply using conductive ink for traces.

But then there are the holes. Or lack of holes. This thing doesn't drill holes, and it's intended to create boards with no holes at all. It makes "double layer" boards by overlapping insulated conductive traces applied on the same face of the substrate. That's clever and a very cool idea, but it's no substitute for drilled holes and two planes separated by the substrate itself. I would have very little confidence in wire attachments made to this type of board, and it definitely is not suitable for applications with any serious voltage differential between layers, or where impedance control or stray capacitance matters. In other words, it's limited to a small and low-performance set of applications. No multi-megahertz digital signals. No RF circuits. No high voltage (or even line-powered) stuff. No high current handling. For $2199, I'll wait a decade and see where this tech goes.

Comment Maybe don't assume all readers are idiots. (Score 4, Insightful) 55

"To achieve the breakthrough, the UW team used a material commonly found in commercial lasers but essentially ran the laser phenomenon in reverse. They illuminated a single microscopic crystal suspended in water with infrared laser light to excite a unique kind of glow that has slightly more energy than that amount of light absorbed."

That is the most detailed explanation in the article of what this phenomenon is and how it works. No names, either for the phenomenon or the materials involved. No numbers, or even quantitative comparisons. No links to the actual research. Who do they think reads this stuff? Random people aren't looking at long-form articles on research posted to university websites. Their whole audience would appreciate a lot more detail than they're giving us.

Comment Re:Why (Score 1) 965

There's a big difference between preparing for the possibility (you don't seriously believe there will never again be war in North America, do you?), ...

"Never" is a very long time.

Will there be a war next week? Probably not (99.999%). Next month? Next year? In the next 10 years? 20 years? 50 years? Have you died of old age or heart disease or such by that time?

100 years? 200 years? 500 years?

Who knows? Destabilization happens fast, and the prelude is usually only obvious in hindsight. The prepper philosophy is to admit that nobody can answer your question and to take some degree of precaution as a hedge against the risk.

Comment Re:^^^^^ MOD THIS UP ^^^^^ (Score 1) 161

Don't look at sun with remaining good eye. And sunlight isn't coherent light, so the comparison is skewed from the start. I recommend that you try looking into an eye-safe laser beam from a few hundred yards away (so the energy of the beam is spread over a spot two to three feet in diameter). The experience will not be dangerous, but nevertheless quite unpleasant, and this little experiment should cure the misconception that looking into a laser from afar couldn't be a problem.

Obviously the lack of temporal coherence in sunlight is irrelevant here. Spatial coherence does have some influence on how bright the source appears. Sunlight is fairly spatially coherent at about 4.7mrad divergence on Earth. That's comparable to a bad laser pointer, and not too much worse than a good one. Coherence is much less important to this issue than M^2 value or other measures of beam "quality" that correlate to focal spot size. The sun wins on those metrics. I've stared into many laser beams of different powers and wavelengths, sometimes intentionally, occasionally accidentally. I've been on the receiving end of high power beams from long distances just to see what it's like. A 150mW 532nm beam of about 1.5mrad (a decent quality DPSS module) is pretty darn bright from 3/4 mile away at night, but it's definitely not dangerous. Try it.

Comment Re:Why (Score 4, Interesting) 965

To the point, militant Islam really, really wants to be in charge, which makes pretty much everyone in the world either an immediate target or a future target. It's odd that you don't seem to recognize that.

Militant Islam isn't a single entity, it's an ideology followed by many competing groups. The attacks happened because someone, or some group thought it would further there goals. They thought it would be a better use of resources than attacking the US, or Hungary, or keeping fighters in Syria (and they might be correct, or they might not be correct, but they thought it would be a good idea). So the real question is, who are these people making decisions, and why did they make those decisions? It's odd that you don't seem to recognize that.

That's like asking why the Nazis chose to invade Poland when they did, looking for some deep meaning or hidden complexity. They wanted to control it - along with everywhere else in the world. It was an easy target, so they hit it. When the goal is total subjugation of all targets, the rationale for which targets are selected first is sort of irrelevant.

Comment Re:Why (Score 5, Insightful) 965

How many "preppers" are there in the U.S. that believe the West is going to collapse into ruin any day now. All it will take is just the right spark to start the race/culture/religious/civil war.

There's a big difference between preparing for the possibility (you don't seriously believe there will never again be war in North America, do you?), versus believing you can bring it about yourself. Preppers recognize the reality that stable, peaceful societies never last forever and often devolve quickly without enough advance notice to avoid the fray. Terrorists believe they can cause that devolution.

Comment Re:Always had a problem with laser pointers (Score 5, Informative) 161

Most laser pointers are class IIIb laser devices.

IIIa, not IIIb. The CDRH requires that handheld pointing lasers meet the IIIa classification, which means less than 5mW output power among other things. Red laser pointers virtually all comply with this. Green pointers are hit-or-miss, since the cheap DPSS laser inside has highly variable power output depending on unpredictable factors. In my experience measuring the power output of green pointers (and I've measured a lot of 'em), they are generally 3-5mW but sometimes you get a hot one that pushes 5-10mW. They can all be cranked up with tinkering though, sometimes to 100mW or more! It's the tweaked green pointers and black-market IIIb and IV devices that cause some concern. 5mW in the eyeball is extremely unpleasant, but does not cause retinal damage - especially with the poor beam quality (and thus large focal spot size) of handheld lasers. A tweaked-out DPSS pointer running tens of milliwatts can definitely cause instant permanent damage at short range though, and the 500mW to 1.5W blue diodes are quite dangerous (but totally awesome).

Here's the thing, though: None of these lasers are really dangerous at long range. The beam quality is universally terrible, which results in high divergence and therefore large beam diameter at long range. The total amount of light produced by even the most powerful handheld lasers is not very much, and quickly loses its brilliance when spread over a circle a few meters in diameter. At one mile, a 2mrad beam will be approximately 10 feet in diameter. A 1W laser would then have an intensity of 0.138W/m^2, or 0.0138mW/cm^2. That's nothing. The sun is over 100 times brighter than that.

Comment Re:Ground to plane windshield geometry (Score 1) 161

I'm curious how someone on the ground is able to aim at the windshield of the cockpit from the ground.

What am I missing here?

You're not missing anything. It's very hard most of the time to hit the windshield of an aircraft from any nearby point on the ground. The hardest part, though, is keeping the laser pointed at the target. It's essentially impossible. People have tested this repeatedly - it's on YouTube. The bottom line is that a handheld laser can only ever manage to very briefly flash the cockpit of a flying aircraft, and the beam intensity at such a range is non-dangerous even if the laser is quite powerful. It may be surprising to a pilot and could cause a brief but dangerous distraction, but the hype of blindness (even temporary vision loss) is grossly exaggerated. Basic math and empirical testing shows that pretty conclusively.

Comment Re:"Strong indication" (Score 1) 190

"Strong indication... likely..."

So, are they priveleged or not?

They are.

There are a lot of people in US prisons, you know, and if there is such a thing as an unpriveleged inmate/attorney conversation (I have no idea how it works), then there are probably a lot of those going on.

There isn't.

What if they call the attorney's office and they're not there? Is that priveleged?

Yes.

All communications between an attorney and client are privileged, with a tiny set of exceptions which are, in general, not applicable here. Calls to an attorney's office are privileged even if the attorney never got on the phone. Communication with the support staff can be just as damaging as communications with the attorney if revealed to the other side. The mere fact of an attorney's consultation or representation is confidential. Much of the time, the fact of representation will be publicly known - but occasionally it can be critically important that a client's consultation with counsel be kept secret. Having the government intercept and record ANY communication with counsel is extremely problematic. Jails and prisons have systems in place which are intended to ensure that phone calls to legal counsel are not recorded (the inmate or attorney notifies the staff that the call is privileged, and a different phone system or procedure is used). The revelation here is that those safeguards are apparently all for show, and they record and archive the calls anyways.

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