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Comment: Re:BLUE ray (Score 2) 194

by kf6auf (#48470367) Attached to: Jackie Chan Discs Help Boost Solar Panel Efficiency
I expect that the reason the efficiency is increased is precisely because the pits are narrower than the wavelength of the light, making it less likely to be reflected and more likely to be absorbed. (You can view this classically as the index of refraction changing gradually.) If you use a pit size greater than the wavelength of the light, you'll end up with each photon either hitting the bottom of the pit or next to the pit, and the pit will have no effect.

Comment: Re:Wouldn't it suffer eminent heat death? (Score 1) 523

by kf6auf (#48423371) Attached to: What Would Have Happened If Philae Were Nuclear Powered?

Here on earth our nuclear power comes from fission reactors producing 500-3000 MWt of heat which we in turn attach to a glorified thermal power plant consisting of water moving in a closed loop through pipes and turbines not fundamentally very different than a steam engine. This nuclear power is instead the radioactive decay of a small radioisotope, emitting a mere 500Wt (but with no way to turn it off because no fission is involved) which we in turn attach to a relatively unconventional thermoelectric generator which doesn't require the giant size or any moving parts (except electrons) which a terrestrial thermal power power plant employs.

In both cases you need a heat source (the nuclear fuel, probably ~500K) and a heat sink (either a large body of water at 300K or the outside of the spacecraft which is a cold ~100K because it radiates any heat into the vacuum of space) and generate electricity from the difference.

Comment: Re:That's not the reason you're being ignored. (Score 1) 406

by kf6auf (#48145351) Attached to: Flight Attendants Want Stricter Gadget Rules Reinstated
Off the top of my head:
How to buckle a seat belt; wear it any time you're seated.
Put your mask on first and that it might not inflate, but that's ok.
Life vests are under your seat, and how to wear one and not to inflate it until after you exit.
No smoking; it is a federal offense to tamper with the lavatory smoke detectors.
The nearest exit might be behind you.
There's a safety card in the seat pocket in front of you showing you how to brace if the plane crashes.
Your electronic devices may crash the plane if you use them, depending on location.
For takeoff and landing, have your seat back upright, your tray table, and all your stuff stowed. Looks like they could just print it on the back of the seat back in front of you.

Comment: Heads in the Sand (Score 4, Interesting) 502

by kf6auf (#47610515) Attached to: Why Morgan Stanley Is Betting That Tesla Will Kill Your Power Company

The utilities are sticking their heads in the sand and trying to pretend that technology won't move forward. In some places they are trying to add an interconnect fee for those with solar panels that's as large as my electricity bill. They also are requiring solar panel inverters to stop working entirely when the grid goes down, instead of just providing power for the house and still leaving the grid upstream unenergized. All this, and the price of electricity keeps going up. And they expect people won't move forward with batteries as technology improves?

Disconnecting from the grid entirely is large investment: people need a large solar array, several days worth of batteries, and probably smart appliances (mainly air conditioners and refrigerators). Or the utilities can make money helping to create a lower-investment intermediate option: staying connected to the grid with a smaller solar array and half a day worth of batteries which both help the utility with load balancing and can keep the house powered when the grid goes down. If they do this right, they will be able to remotely control when the system is storing energy or sending it to the grid, which probably means it's in their best interest if they write the software and maybe even make and sell (and install?) the hardware.

Plus, they can provide monitoring services and, if they want to really diversify, insurance services or financing options. Otherwise, as more people abandon the grid, it will become more expensive per person to maintain it, creating a downward spiral of grid usage.

Comment: Cool but fastest in Australia?? (Score 1) 71

by kf6auf (#47593117) Attached to: Unboxing a Cray XC30 'Magnus' Petaflops Supercomputer
Pictures are cool and all, but there's supercomputer currently at the Australian National University that has been benchmarked at 0.978 PetaFLOPS so saying that this one could be the fastest in the southern hemisphere with up to 1 PetaFLOPS seems a bit like counting your emus before they've hatched.

Comment: Facts Possibly Correct but Conclusions Unrelated (Score 5, Informative) 335

by kf6auf (#46539917) Attached to: Nate Silver's New Site Stirs Climate Controversy

The evidence claims that so far, there hasn't been an increase in monetary cost of natural disasters relative to GDP. I'll let other, more informed people tackle this factual issue.* My problem is purely based on faulty logic; at the end of the article, the author extrapolates that this trend of disaster damage being correlated with and caused by increases in GDP will continue indefinitely. But the only evidence cited for the conclusion that climate change won't ever cause increased natural disasters actually says that US tropical cyclones won't significantly increase in frequency and severity for several decades; I found nothing about winter storms/polar vortex, crop loss due to drought, sea level rise, etc. and I'm not even sure how accurately you can extrapolate to tropical cycles in other places, not to mention many of us hope to still be around in several decades. I appreciate that Nate Silver is a great statistician, but this is going to go downhill really quick if the conclusions of articles posted on his site are only tangentially related to the actual statistics.

*The other disappointing thing is that the author has claimed this before, has been refuted, and hasn't changed his argument even so much as to mention the points made by various people who had rebuttals.

Comment: Re:"Green" (Score 4, Interesting) 318

by kf6auf (#46341043) Attached to: Consumer Reports Says Tesla Model S Is Best Overall Vehicle

Other people have addressed several of your issues, so I'm just going to look at the claim that driving uphill empties those batteries in very little time.

As far as I can tell, the steepest drive in the United States (from the beach to the top of Mauna Kea, HI -- not entirely paved) is approximately 13800ft / 4200 m above sea level. Since the mass of a Tesla Model S is 2100 kg, this would consume 25 kWh of energy (30 kWh if you loaded it with 300 kg of people and stuff and factor in a 93% motor efficiency). The energy stored in a full Tesla battery is either 60 or 85 kWh, depending on the model. The drive from Hilo is 43 mi / 71 km (or Kona is 64 mi / 103 km), which over flat terrain would consume 15 (or 20) kWh, for a total of no more than 50 kWh. Thus, you could easily do the drive in a charged 60 kWh Model S. And, the drive back would be entirely free because you just brake all the way down -- just don't charge it at the top unless you want to burn out your brakes.

In theory, the potential energy of a Model S (+300 kg) on top of Mount Everest is 59 kWh, so I don't recommend that with the 60 kWh battery, but then I suspect you'd have issues trying to drive any car to the top of Mount Everest.

Comment: Re:lumping it in (Score 1) 734

by kf6auf (#46053787) Attached to: Will Electric Cars and Solar Power Make Gasoline and Utilities Obsolete?
It's less about who makes the standards than how good the technology was. Early 1970s nuclear power plants are a lot less safe than new designs. The smart thing to do would be to build two new units for every old unit decomissioned, and we'd have a lower risk of a problem and we'd generate twice the (baseload) electricity.

Comment: Re:Murica Fuck yea! (Score 1) 635

by kf6auf (#46008271) Attached to: U.S. Teenagers Are Driving Much Less: 4 Theories About Why

How are you going to get the groceries back home, make 10 trips? I think I'd prefer to drive.

100m?! Unless you're on crutches, 100m to and from the grocery store is no trouble at all. I used to walk to the grocery store when it was over 300m away and I just carried a bag in each hand and (if necessary) slung a bag over each shoulder. If you prefer, you can bring a backpack. If it's raining, carry one fewer bag so you have a hand for an umbrella. Seriously, unless you're at Costco buying a TV and four cases of beer for a superbowl party, walking a limited distance to do your shopping most weeks isn't hard.

Even if you live 3 miles from your grocery store, all you need is a backpack and maybe a basket or two on your bike and you are set. If you have kids, hook up the kiddie trailer and fill it with groceries too. It's not that hard.

Comment: Re:How safe? (Score 1) 947

by kf6auf (#45249435) Attached to: How Safe Is Cycling?

Believe it or not, most of the time most bicyclists don't like having to share the road with cars either (they belch exhaust right in front of you while you're trying to get as much oxygen as possible, they like to cut you off, they like to swerve into bike lanes without looking before turning, they drive at the speed limit even when it's not safe to do so due to poor visibility, etc.). If a bike is "in your way" chances are it's the only reasonable way for them to get to/from work while on a bike.

Sidewalks (in places where it's even legal to bike on sidewalks) often have low hanging branches, disappear without warning (either into a curb, 100-year old tree, or someone's yard) and you have to go a lot slower because if you're doing 20mph on a sidewalk it's not going to be long before you're going to run into some car backing out of a driveway that isn't looking that far for you.

Which is why there should be bike lanes on more roads. But even then, if you encounter a roundabout or want to make a left turn, you have to deal with cars, and cars have to deal with bikes. As it is, I go an extra 2/3 of a mile out of my way each trip to avoid cars as much as possible.

Comment: Australia has tiers: (Score 1) 568

by kf6auf (#45219619) Attached to: Top US Lobbyist Wants Broadband Data Caps

The fiber provider in my area (Canberra, Australia) has options for n GB(8am-2am) + n GB(2am-8am) where n is 20, 100, or 500. It's $100/month for the 500GB+500GB option at 100(down)/40(up)Mbps. Dropping down to 100GB+100GB at 12/1Mbps costs $60/month, which is what I was paying in Berkeley for Sonic DSL two months ago, and is pretty much the speed I was getting. Once you hit the cap, you're throttled to 256kbps both ways.

Seems reasonable to me. The more I use, the higher percentage of their "tubes" I'm using and the more they need to build.

Comment: Re:Hybrid drives anyone..? (Score 1) 232

by kf6auf (#44867943) Attached to: I use spinning-drive storage media ...

I got a 500GB/4GB one about three years ago. It's definitely faster than my previous (250GB/5400 rpm) drive, but it's also a lot more power hungry and seems to rarely spin down. SSDs, on the other hand, have much lower power consumption and are way faster. If your computer has USB3, you're definitely better off getting a small SSD and a 2TB 2.5" USB3 external drive.

PS. My first one died within a couple months, and this one's SMART says it's been failing for nearly 7 months now, but I'm stuck waiting until it shows a clear symptom or fails Seagate's own utility before I can RMA it.

Comment: Re:Badly worded poll is bad (Score 1) 232

by kf6auf (#44867485) Attached to: I use spinning-drive storage media ...
Technically, none of them are spinning. Both elementary particles (along with many more) have intrinsic angular momentum which we call spin because it's similar to the angular momentum classical objects have when they are spinning. Since (let's be honest here), physicists make up enough words as it is, using an existing word (the noun "spin") when it almost fits is probably a good thing. But the downside is that the verb "to spin" doesn't really apply.

No amount of careful planning will ever replace dumb luck.