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Chevy Volt To Resume Production One Week Early Following Record Sales

ProfessorPillage Re:sure it is (443 comments)

They absolutely are cheaper to drive: the incremental cost per mile driven will be lower on just about any electric car than the equivalent hybrid, and lower on a hybrid than an equivalent conventional car. They just aren't necessarily cheaper in total cost of ownership (this depends on a lot of circumstances), where the difference in sticker price is plainly obvious. They are no more dishonest than advocates for anything else.

The subsidies for the consumption of oil aren't free either (including providing security for supply lines, making pollution and consumption of resources essentially free, tax credits for oil companies, and direct subsidies), so it is not obvious that subsidizing the adoption of technologies likely to reduce oil consumption is bad energy policy or bad tax policy. The stated purpose of tax credits is to encourage taxpayers to take actions that are in the public interest but are not economical in the market (of course there's often brib^H^H^H^H lobbying involved too). So you can equally argue that any policy is bad policy. Get the gov't to stop subsidizing fossil fuels (including the lack of a value placed on leaving the resource in the ground), then we can talk about removing subsidies for technologies that reduce this consumption.

more than 2 years ago
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Chevy Volt To Resume Production One Week Early Following Record Sales

ProfessorPillage Re:sure it is (443 comments)

A Prius is $22k.

According to the Toyota site a Prius is $24,000-$29,805 base MSRP, depending on which version you get. I don't know which one is most comparable to the features on the Volt, but it's probably not the cheapest one.

They also compare it to the all electric Leaf, and the all gas Chevy Cruze.

They list the per-mile costs of those, but they don't do a direct comparison on the time to break even on the difference in price between a HEV and BEV. I don't see an analysis of whether a (mostly) BEV is worth the extra cost over a HEV on the wikipedia page nor the pages it links to.

The battery probably will last longer than the warranty period, but did you read where Chevy estimates that it's capacity will be reduced 10%-30% in those 100k miles? Oh, BTW, that's 100k vehicle miles, not 100k electric miles. By the time you hit 100k-150k electric miles, the battery is expected to need replacement, if for no other reason than significant loss of capacity.

That's not a thorough analysis of the mean lifetime a buyer can expect for a battery given any replacements they might get during the warranty period. It only makes sense to buy a Volt if the vast majority of the miles will be electric, so it makes sense to assume most of the miles will be on electric. If you frequently need a longer range, you are probably better off with a car that has a longer range at high efficiency.

The Edmunds analysis you cited says that the payback period is 135K miles at $5/gal which is within the expected lifetime of most cars, and it seems to be around 90-100K miles for the more common HEVs (the full-electric leaf is at the low end of the range). But number of years to break even on a price premium is not the same thing as total cost of ownership- what you really want is the total discounted purchase, fuel and maintenance costs over a given number of years/miles, minus the residual value at the end of that period. And yes, you might have to replace the battery (or maybe it'll get replaced under warranty). You also might have to replace parts on other cars.

So if you only care about total cost to yourself (it's beyond me why anyone thinks buying a car is a good way to save money), and you will generally drive within the electric range, and you expect gas prices to rise significantly relative to electricity prices, then your total cost of ownership will almost certainly be lower with a Volt than with a regular gas car, some HEVs would probably "save" you more, and a full-electric (if the range works for you) is probably the best deal. If gas prices stay the same, you'll probably have similar total cost of ownership either way. Not owning a car at all will save you more.

These arguments that electric vs gasoline cars are a bad investment remind me of the exact same argument a few years ago about how hybrids, and now people like you are insisting on comparing electric cars to hybrids to decide if they're "worth it." Lots of people buy SUVs. How long do those take to recover their price premium?

more than 2 years ago
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Chevy Volt To Resume Production One Week Early Following Record Sales

ProfessorPillage Re:sure it is (443 comments)

The link you listed mostly compares electric and other hybrids to conventional vehicles, not so much to each other. And they do this at current gas prices, and up to $5/gal. I think the $19K CR-Z HEV you're comparing it to is not comparable to the Volt - it's smaller, and also gets under 40mpg (the Insight is also smaller and also gets in the low 40s). A Prius costs more like $25K (advertised as ~50mpg, probably less in independent testing like the one you're using for the Volt), and a Focus is like $28K (~40mpg advertised). So it you really want to get picky on details, the gas price to break even vs. the Focus in 100,000 electric miles is $0.08/gas-mile or $3.20/gal, and vs. the Prius it's $0.11/gas-mile or $5.50. That is assuming all-electric miles, but presumably the battery will last longer than the warranty period, and the advertised mpg for the HEVs are probably high. Also, a battery replacement 8 years from now should be cheaper than the purchase price premium.

more than 2 years ago
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Chevy Volt To Resume Production One Week Early Following Record Sales

ProfessorPillage Re:sure it is (443 comments)

My sister called me a few weeks ago. She works 3 days a week as a nurse working 12 hour shifts at a facility about 60 miles from her house. She has a vehicle that gets about 20mpg and is in great shape. More than that, it is 100% paid for. She wanted to know my opinion on getting a new car.

So even if she had a car that was able to get 40mpg, her gas consumption would go from 9 gallons a week down to 4 gallons at best. 5 gallons at $5 a gallon is $25 a week or $100 a month. A new car payment would be better than $250 a month.

That's off by a factor of two, assuming she also drives home from work. She probably drives other places too.

All of the extra nasty non-green things that goes into manufacturing your lightweight car, motors and batteries PLUS using electrical current generated by coal burning plants. All you have done is moved WHERE the environment is polluted at from your exhaust pipe, to someplace else. You are not really saving the environment either.

Actually, even including battery, etc, and manufacturing, and assuming all electricity come from coal, electric cars still cause less total pollution than conventional ones burning gasoline (though this depends on how you assign relative values to different types of pollution). The difference becomes much more significant when lots of the electricity comes from sources other than coal (in the US, 60% comes from non-coal sources). Of course the only way to "save" the environment using transportation choices is not to drive, and to remove the perceived need for others to do so as well.

more than 2 years ago
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Chevy Volt To Resume Production One Week Early Following Record Sales

ProfessorPillage Re:sure it is (443 comments)

If you compare a 50mpg HEV with a 4mi/kWh BEV, you save about $0.13/mile using the BEV with $8/gal gas and $0.12/kWh electricity. This works out to about 75,000 miles to break even on a $10K price difference. But the Volt's a bigger car than those hybrids you listed, so it's not really a fair comparison.

more than 2 years ago
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Drug Turns Immune System Against All Tumor Types

ProfessorPillage Re:Interesting times we live in... (330 comments)

Also remember that research is known to cause cancer in mice, and live accordingly.

more than 2 years ago
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Pac-Man Is NP-Hard

ProfessorPillage Re:What does the hell does NP Hard mean? (195 comments)

Right, except that NP-hard problems don't have to be in the NP class, they can be harder. They are the problems, not necessarily in NP, that are at least as hard as the hardest problems in NP. You're thinking of NP-complete or equivalent.

more than 2 years ago
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Engineered Stomach Microbe Converts Seaweed Into Ethanol

ProfessorPillage Re:Nice from a tech point of view, *BUT*... (226 comments)

Your argument is fundamentally flawed, because ultimately, any energy generation will result in rising global temperature. After all, heat is the ultimate byproduct of reducing local entropy in any system.

No, the amount of heat released by energy production is to small to make a difference (it is tiny compared to the incoming solar radiation), and radiates to space quickly. Systemic changes to the equilibrium are the problem- mainly increasing the amount of atmospheric greenhouse gases that trap some of the energy from sunlight, but also things like changing the surface albedo through land use changes.

more than 2 years ago
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Zappos Hacked: Internal Systems Breached

ProfessorPillage Re:Storing passwords (not as easy as you think) (122 comments)

Because the linked article you were complaining about specified a calculation prefaced with "suppose you want to precompute the hash values for all valid characters on a US-English keyboard", about the amount of storage needed for a rainbow table. Of course there were other errors in the article, but you picked on a relatively minor part that was correct. UK keyboards have something like 13 more characters than the US one, which increases the number of possible 8-char passwords using the keys on the keyboard by a factor of about 3 relative to the US keyboard (108^8 / 95^8); and US-letters-and-numbers-only reduces the possible number only by a factor of about 30 (62^8 / 95^8). You could make a similar rainbow table for each keyboard layout, many of which have similar numbers of easily accessible characters, with a similar amount of storage to that described, so his numbers are not meaningless. So the lesson is, use a hash that incorporates salt, and don't use dictionary words as your password.

more than 2 years ago
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Zappos Hacked: Internal Systems Breached

ProfessorPillage Re:Storing passwords (not as easy as you think) (122 comments)

26 uppercase, 26 lowercase, 10 digits, 12 punctuation/space = 74.

No, the digit keys all have special characters when you hold shift, and the 11 special character keys all have 2 choices as well, so there are 33 special characters on the keyboard including space. That's 95 total. Look at your keyboard and count them.

I think this throws off the rest of your calculations. The 43 numbers and punctuation together are a lot more than the 26 lowercase letters. And you failed to take into account that, even when done in a stupid way, people are likely to switch around the order somewhat (uppercase at the beginning OR end of the letters, and number/punctuation in either order, and sometimes even at the beginning instead of the end), which adds a few factors of 2 at least. Even one number and one punctuation in either order is about equivalent to two lowercase letters, but better because they help reduce dictionary words. I'm with you on explicit requirements of numbers and numbers only.

But yeah, you're better off either encouraging but not requiring some punctuation and numbers, or having looser requirements like the common "at least 1 each of 3 of the following types: upper, lower, numbers, punctuation", plus some restrictions on sequences, dictionary words, etc. It's probably a good idea to require something like at least 6 non-numbers for an 8-character-minimum password too, to keep 7-number plus 1-letter passwords from getting too popular. But if you're coming up with your own password solution (like just about everyone with the type of requirements you describe), or copying one from a non-expert, then you're probably doing it wrong.

more than 2 years ago
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Zappos Hacked: Internal Systems Breached

ProfessorPillage Re:Storing passwords (not as easy as you think) (122 comments)

It's hard to take seriously an article which contains remarks like the dumb:
"26 letters, 10 numbers, 11 other character keys for a total of 94 characters"

This part is right: (26 + 10 + 11) * 2 = 94. But yeah, he forgot space so it should be 95.

more than 2 years ago
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Prospects Darken For Solar Energy Companies

ProfessorPillage Re:Just wait until Iran blocks the Strait of Hormu (435 comments)

They're not trying to measure energy, they're measuring peak power capacity. It's shorthand for $1/Watt fixed cost plus $0/kWh incremental cost. You'd do the same thing if you were buying a power plant ($X per MW fixed cost + $Y/kWh incremental cost), though in general the incremental cost varies and there are daily fixed costs as well. You do get that Watt for all the time maximum sun is shining on it and it is hooked up, until it stops working.

more than 2 years ago
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Inductive Charging For EVs To Be Tested In Berlin

ProfessorPillage Re:Problem? (123 comments)

Did you forget that there are many hours in a year, and multiple square feet on a roof?

more than 2 years ago
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Massive Radio Telescope Starts Observing the Skies

ProfessorPillage Re:Too bad (44 comments)

You're talking about two different kinds of waves. Matter is also a waves in the quantum mechanical sense. EM in some cases is better described by waves in the classical sense, i.e. with Maxwell's equations. Though often EM is better described as photon particles, or as photon waves that describe things like the probability of being detected at a given location.

about 3 years ago
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Massive Radio Telescope Starts Observing the Skies

ProfessorPillage Re:Too bad (44 comments)

I think it has to do with both the photon density and the size of the thing you use to observe them. If there are few photons per cubic wavelength (even less than one), EM waves look more like photons in the sense that you need to describe them with quantum mechanics. If there are many, they look more like classical waves. Also, if the wavelength is small compared to the observer, then they are more likely to look like photons. So if you have 1 photon/cm3, and a wavelength of 1cm, it might look more like a photon in that you observe quantum behavior because there is 1 photon per cubic wavelength. But if the wavelength is 1m, then there are 1,000,000 photons per cubic wavelength and you will observe more wave effects with a detector small compared to 1m, or it will still look like particles if your detector is large compared to 1m. Both views can accurately describe them, but one might be more informative in a given situation.

The size of a photon is tricky. They can be spread out over an arbitrarily large area, with a probability distribution of "appearing" at any given spot in that area. The spot in which it would appear (for example to be absorbed by an antenna) would be wavelength-sized, in the sense that this is the amount of space over which it would interact with something. I believe this means cubic-wavelength (or square-wavelength times period if you want to look at it that way), but I'm not completely sure. But if you're thinking about it as a particle, then you can probably think of it as a point, because if its size was relevant, you'd be thinking about it as a wave.

about 3 years ago
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Quantum Coherence Found Fueling Photosynthesis

ProfessorPillage Re:Those helpful links (135 comments)

Measuring the even-numbered electron 'affects' the result of measuring an odd-numbered one (or another even numbered one) because they are entangled, not because they are coherent, though I suppose in a sense coherence would be what makes the result predictable. Please provide an example of coherence (in terms of spin only) where the particles are not entangled. I don't think it's possible, because I don't think coherence means anything useful in terms of spin only. Any two electrons would trivially be coherent (in terms of spin) because they differ by a fixed phase angle, unless in this case coherent also means in-phase (i.e. having the same spin).

You do need coherence in the double-slit experiment in order to observe a distribution of points where the electrons hit over time that match the same interference pattern they would have if they were all interfering with each other as a classical wave. If you vary the direction or energy of the electrons, for example, you would not see such a pattern.

about 3 years ago
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Quantum Coherence Found Fueling Photosynthesis

ProfessorPillage Re:Those helpful links (135 comments)

That's entanglement, not coherence.

In your first example, they are entangled and coherent. In the second example, they are entangled and the odd-numbered electrons are coherent, as are the even ones, but they are not coherent with each other. Though I'm not sure coherence means much when only looking at a single discrete attribute like spin. I think you want either a continuous attribute, or multiple discrete ones.

The double-slit experiment (e.g. with electrons) is a better example of coherence. You shoot an electron through a double-slit. The electron-wave goes through both slits, interferes with itself, and has a higher probability of hitting in the points with constructive interference (when measured by contact with the target), and a lower probability of hitting the points with destructive interference. Shoot more electrons the same way, and they land according to the same probability distribution. The electrons are coherent because they have the same wavefunction after passing through the slits and interfering with themselves, whether they go one at a time or they are in a beam. However, they do not all hit at the same location because their trajectories are not entangled.

In the context of photosynthesis, I'm guessing this means that the electrons that are moved by the energy from the photons follow paths that are more limited than you might expect from classical physics, because the of interference in the wavefunction among the different paths. (I am also not a physicist).

about 3 years ago
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Gas Powered Fuel Cell Could Help EV Range Anxiety

ProfessorPillage Re:I must be misunderstanding (162 comments)

First of all, you're ignoring the amount of energy required to import and refine the gasoline. I've heard estimates as high as 8kWh per gallon for refining. Most of the power plants in the country use coal, which doesn't have an energy intensive refining process.

Well-to-tank efficiency for gasoline is around 80%. Mine-to-power plant for coal is around 90%.

Secondly, you're ignoring the fact that 40% of electric vehicle owners have solar panels. This negates that pesky coal power plant and its transmission deficiencies.

That's only relevant if the ownership or operation of the solar panels is dependent on the use of the EV. If they'd have the solar panels anyway, then the decision to use an EV mostly affects the electricity markets in the use of marginal power plants (which tend to be fossil-fuel powered), and the system-wide decisions on deploying other power sources (where the use of EVs is likely to encourage more renewables). It doesn't matter much whether the owner has solar panels themselves.

If you compare the efficiency of the vehicle itself, when you put electricity into an EV, it is 85%+ efficient. If you put gasoline into a car, it is 25% efficient (max). With a gasoline car, no matter what technology comes out, that vehicle will never be more than 25% efficient.

No, an EV is at most 80% efficient (plug to wheel) with current technology. It does allow more flexibility in energy sources, though you can potentially have non-fossil liquid fuels too. Gasoline cars are only limited to something like 25% efficiency (tank to wheel) if the gasoline is converted to useful energy using combustion. If you use a fuel cell, it can be much higher, which is the point of the article, using a FC instead of an ICE for extending the range of an EV.

about 3 years ago
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Gas Powered Fuel Cell Could Help EV Range Anxiety

ProfessorPillage Re:I must be misunderstanding (162 comments)

They did include generation. Burning gas in an ICE is equivalent to burning another fuel at the power plant. They did not include fuel production in either case (you also have to dig up and process coal and natural gas). The only thing unfairly left out was transportation of gas from the refinery to the pump, which is a small energy expenditure compared to the ranges given for everything else. Given that it's just a ballpark estimate, it's not bad. The ICE efficiency and transmission losses both look a bit high, but not enough to make a huge difference.

What this shows is that BEVs are more efficient than ICEs even if you get all of your electricity from coal (and hopefully, you don't). But fuel cells are more efficient at converting their fuel source to electricity than any process involving combustion, which isn't really surprising. Of course it's best if you can power your FCEV on something other than fossil fuels, and the same goes for BEVs.

about 3 years ago
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Physicist Uses Laser Light As Fast, True-Random Number Generator

ProfessorPillage Re:And the numbers are... (326 comments)

Sure I can, with 2 additional lines of code: one outer loop that iterates through all possible seeds, and another that iterates through all known pseudo-random number generator algorithms.

about 3 years ago

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