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Comment No, they handle 1.2% of all retail sales (Score 1) 58

TFA says they handle 15% of all online retail sales, maybe 20%-30% if you include third party sales handled through Amazon. Online sales comprise only 8.1% of all retail sales. So Amazon's (very small) slice of the whole pie is just 1.2%, possibly 1.6%-2.4% if you include their third party affiliates.

Amazon barely cracked the top-10 stores in retail sales for 2015. There's a tendency for people who like to be online to over-exaggerate the effect of the Internet. Retail sales are still very much a brick and mortar business.

Comment Re:For all the night shift Tesla owners (Score 3, Informative) 80

Localization of the power source doesn't matter. Everything is interconnected by the grid anyway, so only total generation and total consumption matter. Say everything except your Tesla uses x kWh.
  • Original case: x kWh generated, x kWh consumed.

Now add the Tesla and solar panels on your house:

  • Work night shift, Solar panels generate y kWh, Tesla consumes y kWh to charge (set them both to y to simplifiy):
    x + y kWh generated, x + y kWh consumed
  • Work day shift, Solar panels generate y kWh which is sent to the grid, Telsa consumes y kWh from the grid to charge:
    x + y kWh generated, x + y kWh consumed. Same as above.

Basically, if you work the day shift, the addition of your solar panels at your house reduces the amount of power the coal plant needs to generate by y kWh. When you plug the Tesla into a charger at work, it increases the amount of power the coal plant needs to generate by y kWh. And the whole thing is a wash. Exactly the same as if you charged the Tesla at home using (only) power from your home solar panels.

A lot of people don't seem to get this. The marginal increase power use doesn't have to be directly connected to the marginal increase in power generation to have the same effect. This is also why you should conserve electricity even if you're in the Pacific Northwest which is powered mostly by hydroelectric. Any reduction in your consumption means a little bit of hydro power is left over and can be transmitted to the rest of the country, and a coal plant elsewhere needs to burn a little less coal. Exactly the same as if someone living next to the coal plant conserved electricity.

For the same reason, EVs are predominantly powered by electricity from coal and natural gas, not by renewables. Those are the two power generation sources which are flexible enough to ramp up with increases in demand. EVs are only powered by electricity from renewables if you wouldn't have built the renewable plant if you hadn't bought the EV. If you would've built the renewable plant anyway, then it results in a marginal decrease in the generation from coal and gas, while the addition of an EV results in a marginal increase in the generation from coal and gas. So the EV's power is coming from coal and gas. This is the case even if the electricity from your solar panels are going straight to your EV. If in the absence of your EV the electricity from your solar panels would've instead gone onto the grid, then by putting it into your EV you are depriving the grid of those kWh, and a coal/gas plant elsewhere needs to generate those kWh.

Tesla understands this, which is why they're trying to link home solar installation with EV car purchases. If you can link the two, then the purchase of the EV results in the installation of PV solar generation which would not have existed without the EV. And then you can truthfully say the EV is being powered by electricity from solar.

Comment Re:Thankfully NASA took the pictures (Score 1) 108

NASA was much the same before the Challenger accident. The PR people had way too much power - enough to force a launch to proceed when the engineers were saying it wasn't safe.

I'm willing to cut the ESA a little slack here. Nobody was really hurt by trying to de-emphasize the lander's failure, and the bulk of the instruments are in the orbiter (which will also serve as a communications relay station for future missions). So while the mass media obviously was focused on the lander's failure, from a scientific standpoint the orbiter's success was the bigger story.

Comment Re:Weird... (Score 1) 66

That's a key difference between how regular people and rich people tend to think about money. $x million is an amount. Income is a rate. Regular people think having a large amount of money is being rich. $100 million > $50 million, so they'll take the $100 million. Rich people think having a high income is being rich. $100 million earning 5%/yr is increasing at $5 million/yr. $50 million earning 40%/yr is increasing at $20 million/yr, and will exceed the value of the $100 million in 5 years,. So they'll likely consider the $50 million to be the better choice. You can see this among lottery jackpot winners. The long-term payment (over 20-30 years) is usually the better choice, but most winners opt for the immediate lump-sum payment.

Likewise, Microsoft offered to buy FB for $24 billion because they thought that was the best place to invest their money to get the highest return on investment. Zuckerberg turned down the offer because he thought his highest ROI was in continuing to work on improving FB, rather than taking the money and investing it elsewhere. 50% of new companies fail within 5 years; 2/3rds fail within 10 years. So if you think the company you currently own is likely to experience strong growth, selling it with the intent of using the money to start a new company is a very risky proposition.

Comment Re:Walmart also uses direct solar (Score 1) 57

This. Commercial PV panels are about 18% efficient at converting solar energy into electricity, and the best fluorescent bulbs are about 15% efficient at converting electricity into light (the rest becomes heat). So if you install PV panels to power your lights, you're only converting about 2.7% of the sunlight hitting your solar panels into interior light.

In other words, covering your roof entirely with PV panels gets you as much solar lighting as cutting holes in 2.7% of your roof. The little squares in the Walmart pic you've linked covers about 1/12th the roof (one per 3x4 grid), or 8.3%. So it's providing 3x more free lighting than if you'd covered the entire roof with PV panels. Most of the warehouse stores I've been to (Costco, Home Depot, etc) use similar natural lighting extensively. (Note that you can still cover the space in between these skylights with PV panels.)

Comment Re:Economics? (Score 1) 336

0.9 is the historical capacity factor for nuclear in the U.S. Yeah, nuclear is really best for base load. It's slow to ramp up or down, so is not very good for peaking power load (the hourly and instantaneous spikes and dips in power consumption for the grid overall). Peaking load is usually handled by hydro and gas plants, sometimes coal.

The difference is that nuclear power proponents do not advocate making 100% of power generation nuclear. They are ok with using hydro, gas, wind, solar to handle peaking load. Renewable power proponents OTOH advocate 100% of our power come from hydro, wind, and solar, even though none of them are suitable for base load. Geothermal was really the only viable renewable for base load, but it has become collateral damage in environmentalists' war against fracking. (The energy of earthquakes triggered by fracking was already in the earth. If that energy hadn't been released by the fracking, it would've been released in a natural earthquake some time in the future. But in their zeal to shut down fracking for oil by incorrectly blaming fracking for all the energy released in an earthquake, they've poisoned public perception so that geothermal would also be blamed for earthquakes.)

As for rates for different power sources, wind is getting close to nuclear, but solar is still nowhere near. And as mentioned above, neither are suitable for base load. Most of the articles I've read proclaiming renewables will overtake nuclear and fossil fuels in cost mistakenly omit capacity factor in their comparison. They wind up comparing peak generating capacity, which has very little to do with rates. Theoretically you could use renewables for base load if you had sufficient storage capacity. But the most efficient storage system (pumped storage) only has about 75% efficiency, so that automatically makes it at least 1.33x more expensive than its source.

Comment Re:Economics? (Score 3, Insightful) 336

Nuclear power has a capacity factor of about 0.9. So a 1 GW plant will generate on average 900 MW throughout the year after taking into account downtime for maintenance and refueling.

8766 hours in a year (taking into account leap years), so that's 7889 GWh per year.

At a U.S. average rate of 12 cents/kWh = $120/MWh = $0.12 million/GWh, that's $947 million worth of power generated per year.

Nuclear plants are licensed to operate for 40 years. So that's $37.9 billion worth of power generated over 40 years.

Most of the older plants have had their license extended to 60 years. Some are requesting an extension to 80 years because everything is working just fine. So the actual power generated over the lifetime of the plant will likely be 1.5x to 2x higher.

So yeah, the $4.7 billion construction cost is tiny compared to the return you'll get. For your example of a 3.2 GW output plant that costs £24.5 billion ($30 billion) including financing, at the UK average rate of US$0.22/kWh, the expected power generated over 40 years would be worth $222 billion.

Comment Re:Guessing the real story here (Score 1) 88

The interesting thing is that they're implying the FBI was the source for these requests. The NSA and CIA have been able to weasel through their requests on the grounds that they're investigating electronic communications with people outside the U.S. who don't have Constitutional protection. i.e. Someone in California emails someone in Virginia, both are protected by the 4th Amendment, and there needs to be a warrant before their communications can be read by the government. But someone in China emails someone in California, and the NSA and CIA's legal argument is that the Chinese sender doesn't have 4th Amendment protection, so they are within their rights to intercept communications en masse without a warrant, then filter out entirely domestic communications which would require a warrant, leaving only international communications.

The FBI does not have jurisdiction outside of the U.S. (that's the CIA's and NSA's job). The only time they're allowed to investigate something outside the U.S. is when a foreign country invites them to do so (e.g. Pan Am bombing over Scotland). So if it was in fact the FBI which made the request, I'm curious what sort of legal argument they used to get this type of widescale monitoring approved by the FISA court.

Comment Re:Numbers (Score 1) 53

China's GDP is about 2/3rds that of the U.S. So yes it is a bit surprising that iOS app store revenue is greater for China than for the U.S. My guess would be the later introduction of the iPhone and iPad into China means people there are still in the "stocking up on apps they want" stage, while Americans left that phase 4-5 years ago.

Comment Re:So it appears . . . (Score 4, Interesting) 183

The burn cut off 19 seconds before loss of signal, so the probe was in freefall for at least 19 seconds. From TFA:

Not only is the chute jettisoned earlier than called for in the predicted timeline, but the retrorockets that were due to switch on immediately afterwards are seen to fire for just three or four seconds. They were expected to fire for a good 30 seconds.

In the downlinked telemetry, Schiaparelli then continues transmitting a radio signal for 19 seconds after the apparent thruster shutoff. The eventual loss of signal occurs 50 seconds before Schiaparelli was supposed to be on the surface.

That last sentence, if you assume loss of signal corresponds to impact with the ground, suggests de-orbit velocity relative to the ground was much higher than expected. The early parachute release may have been the culprit. Or the probe entered the atmosphere at too steep an angle (which could also explain the early parachute release - the probe would've entered higher density atmosphere more quickly thus increasing aerodynamic load on the chute to the point at which it failed). The burn probably began at a higher velocity than it was designed for.

If we're speculating, my guess would be the higher velocity when the retro-rockets were fired caused greater instability - aerodynamic forces caused the probe to rock more than expected. The parachute's purpose isn't just to slow the craft down; it also keeps the craft's orientation stable during this period of higher aerodynamic forces. Without it, drag on tiny asymmetries on the front of the craft can result in large turning moments. With a parachute attached, these moments are countered by the righting moment the parachute imparts on the rear of the craft every time it deviates from the proper orientation. Without the parachute, the craft can experience large oscillations or even flip due to these drag-induced turning moments. The large amplitude and higher frequency of the resulting oscillations could've exceeded what the rocket control software was designed to handle, and it shut off prematurely when it exceeded some threshold programmed into the software.

Comment Re:MagSafe have save me tons of money (Score 1) 307

My sample size is small, but I've had friends/clients come to me with 2 flaky Macbook AC adapters (with magsafe cords), vs 3 failed PC AC adapters and 1 failed laptop power socket.

If you factor in that PC laptop sales are approx 9x Mac laptop sales, the magsafe AC adapters have a 4.5x higher failure rate than the PC AC adapters.

Also, realize that magnetic power cords were used on deep oil fryers (where the cord trip hazard is much more serious) for decades before Apple used it on laptops. The only reason it's not used on PC laptops is because nobody wants to spend the millions it would cost to challenge a patent that was incorrectly granted to Apple for a pre-existing invention.

Comment Why is anyone making a 4GB device in 2016? (Score 1) 82

Here are the spot prices for MLC NAND flash memory. There's been a (probably temporary) spike in the last month, but the long-term average price has been:
less than $10 for 64GB
less than $5 for 32GB
$2.50 for 16GB
about $2 for 8GB
about $1.80 for 4GB.

Why in the world would anybody make a 4GB device in 2016? Bumping up to 16GB only costs about 70 cents more per device. I tried to buy a 2-4 GB microSD card for my Roku because people said it didn't need any more, but there weren't many available anymore and the price difference was so negligible it was easier to just get a 16GB card.

Comment Re:A quote comes to mind (Score 1) 46

An old boss of mine said "If you had time to do it a second time, you had enough time to do it right the first time".

That shows a gross ignorance of the probability tradeoff involved here. Just because recall expenses for one product exceeded the marginal design cost to "get it right the first time" doesn't mean that's the most cost-effective way to design everything. The ideal production point isn't to design and manufacture everything so you never have to do a recall. It's to build stuff so that most of the time you won't need a recall. And the few times you do need to recall a poor design, the cost of that recall is cheaper than having to overdesign everything. If you issue n products and

  • overdesigning each cost $x
  • designing them with a slimmer safety margin would only cost $(x-y)
  • with the slimmer margin you average 1 recall per n products at a cost of $z

Then "doing it right the first time" has a cost of n*$x, while living with the slimmer margin results in a cost n*$(x-y) + $z = n*$x - n*$y + $z.

So as long as n*$y (the total amount of money saved by designing all products to a slimmer safety margin) exceeds $z (the cost of the single recall), then suffering the occasional recall is the more efficient economic strategy. I know everyone would prefer having all their toys be perfect, but that perfection would come at the cost of you being able to afford fewer toys. You are actually able to afford more toys which work as if they were perfect if you're willing to accept that a few toys won't be perfect, than if you demand all your toys be perfect.

The tradeoff gets muddled when lives are at stake, since it's difficult to place a value on a human life. (Well, placing an economic value on one is easy. Social, emotional, and moral value is difficult.) But we're talking about a smartphone. A modern convenience which didn't even exist 20 years ago.

Also, the manufacturers aren't who you need to convince here. The people you need to convince to change are the idiot reviewers in the media who pan any phone which doesn't match their misguided preconception of what a "good" phone is, and the people who buy based on those reviews. Everyone here complains phones are too thin, and most of the people I know just end up putting a case on the phone to make easier to hold. Bendgate disproved the notion that metal was better, with quantitative measurements showing that the plastic phones were equal to or stronger than the metal phones at resisting bending. And most reviewers don't use a review phone long enough to run down the battery multiple times under real-world use conditions (loaded with lots of background apps sucking power throughout the day), so tend to undervalue the importance of long battery life. The manufacturers just build to the unrealistic market expectations created by ignorant and misguided reviewers.

Comment Re:I hope Apple Pay will die (Score 1) 283

It saves the banks money because it drastically reduces the fraud rate. So, no consumers are not paying for this

Banks and credit card companies do not pay for fraud. They've set it up so the merchants pay for fraud. If you spot a fraudulent transaction on your card, request a chargeback, and the bank approves it, the merchant is out the money and the merchandise - they've paid for the fraud. The fees the banks and credit card companies collect pay for transaction costs, and for people who default on paying back their credit card debt.

Also, it's disingenuous to claim the merchant or customer does not pay for these fees. The credit card companies got laws passed making it illegal for merchants to charge an extra fee for credit card transactions. Consequently when you buy something with a credit card, it's the same price as if you paid in cash (a rare exception being stores which use the "cash discount" loophole). So the fee is coming straight out of the merchant's markup on the item sold - the merchant is paying for the fee. If you want to kick it up one more level, the merchant has to raise its prices to compensate for this reduced effective price markup. So the fee is coming out of the customer's wallet, with cash customers subsidizing the fee for credit card customers since their transactions do not incur the fee, yet they still pay the higher price.

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