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Comment Sadly, gas is cheaper than electricity in CA (Score 3, Interesting) 688 688

I just bought a Ford C-Max Energi; but I bought it strictly for the green carpool-lane sticker.

In California, if you live in a big house, your marginal cost of electricity is shockingly high. For me, it's $0.33/kilowatt-hour.

My Energi goes 20 miles with a 8 kWh charge. That's $2.64 On gas, it gets about 35 mpg. If gas is $3.50 (current price) that's $2.20.

Now, during mid-day on a sunny day, I can charge it much cheaper on our solar panels (currently we are selling power back to PG&E, but at $0.11/kWh) and I do that. I also charge it at work, where it's 'free'; but I live 50 miles from work so I can't keep the car charged just at work. The 'free' power at work won't last forever, either.

You may ask "why not get a Tesla?" Good question. It turns out that there are (at my company) 3x the number of electric-ish cars as there are charging stations, so we have to swap them out after just a few hours. The Tesla would take all day to charge. Also, the Tesla is such a lumbering overpowered beast that it gets substantially less miles-per-kilowatt-hour.

Thad

Comment Reading her mind... (Score 1) 132 132

Somebody I know started taking antidepressants some time ago, and they helped the depression quite a bit. One curious thing, though, is that once she is taking them, she assumes that I can read her mind; that I obviously know what she is thinking. She stopped taking them for a while, and it was immediately apparent that she no longer felt that way, then when she started taking them again, it was back.

Comment Re:$30 (Score 4, Informative) 515 515

DreadPirate, you are really not calculating correctly. I know it sounds cheap, but it isn't. If you can get there for $30 in gas, that's 40 miles per gallon -- not bad. Still, that's 7.5 cents/mile.

Say you bought a used car for $10,000, and can drive it for 100,000 miles. That's 10 cents a mile. More than gas.

Oil changes every 5,000 miles at $40? That's another penny a mile.

Tires at $300 every 30,000 miles? Another penny a mile.

Let's not talk about what your time is worth (you might really enjoy the drive), or insurance (not too dependent on miles driven) -- but still, that's about 20 cents a mile, or $80.

Most people don't really like to think how expensive driving is, but it isn't cheap. We have been taught that it's all about the gas, but it just isn't.

Comment Re:why so long (Score 3, Interesting) 136 136

It's kind of interesting.

One of the big reasons that they thought it would be limited to 90 days is that the solar panels get covered in dust, and as that happens the amount of energy collected diminishes. They figured in about 90 days, based on previous missions to Mars, they'd be out of juice.

And...for the first 50 days or so, it was going that way. And then, a whirlwind came by, and scrubbed the rover clean. This has happened many many times since. An unexpected good fortune.

Comment Re:cryptobracelet (Score 2) 116 116

We'll see.

It's absolutely wrong that I am proposing a 'stealable' ID. No, it's not that at all. Like NFC (ApplePay and others) you don't send out your ID, your bracelet will engage in a two-way conversation that uses generates unique identifiers every time that prove that it's you without giving the system communicating with you the ability to impersonate you. It's not hard at all; we should have been doing this years ago. This is described in Bruce Schneier's Applied Cryptography twenty-fucking-years ago. Chapter 21(Identification Schemes) describes "zero-knowledge proof of identity". Curiously, researchers Feige, Fiat, and Shamir submitted a patent application in 1986 for this, but the Patent Office responded "the disclosure or publication of the subject matter ... would be detrimental to the national security..." The authors were ordered to notify all Americans to whom the research had been disclosed that unauthorized disclosure could lead to two years' imprisonment, a $10,000 fine, or both. Somewhat hilarious, as the work was all done at Weizmann Institute in Israel.

That said, I do think that groups like the NSA and FBI have been quite successful in keeping people (like Jeff4747) remarkably uneducated. Banks, credit card companies, and groups like Google that make gigabucks tracking people have held back from doing things right as well -- and they're paying for it today.

To say again. It is easy to build a system that would securely verify that you have authority to do something, without giving the ability for somebody else to impersonate you. It's somewhat more challenging than printing number in plastic on a credit card, but only a tiny bit more challenging.

This will happen. Once it does people will wonder why it took so long.

Comment Re:cryptobracelet (Score 1) 116 116

The problem with phones is that you can lose them or break them or have them stolen. I agree that it's a good place to start, though.

I believe that the RFID tag that Coren22 suggests don't have, and can't have, the processing power required to do this right. You don't want to say "Yes, I'm 132132123123", that would be *way* too easy to fake. You want to have a back-and-forth communication that shows that you are who you are, without giving away your ID.

I think the bracelet would become a status symbol -- the status being "yeah, I care about security." I'm actually not kidding.

Comment cryptobracelet (Score 1) 116 116

At some point, and my guess is pretty darn soon, reasonable people are going to have a very secure cryptobracelet that they never take off, or if you take it off it will never work again.

The bracelet would work like the NFC chip in current phones, it would create unique identifiers for each transaction, so you can be verified that you are who you are without ever broadcasting your identity.

Then, all email and every other communication can easily be encrypted, securely, and without adding complication. You won't have to worry about remembering a hundred passwords, or about what happens when the store you bought things from is hacked, or that a library of 100 millions passwords will find yours.

I grant that some will protest that this is not natural (I don't want to wear something on my wrist!) but people do a hundred other unnatural things every day (brush their teeth, use deodorant, wear glasses, live longer than fifty years...) The benefits will be enormous, the changes minimal, and this will be led, I believe, by thought leaders.

Comment Re:Tesla's battery is around $400/kWh .. (Score 2) 330 330

If the difference in list price of the expensive to the super-expensive Tesla is only $10,000; I would expect that at least 30% of that price would be extra profit for Tesla. Kind of like the gold Apple Watch. So their cost is probably less than $250/kWh.

Comment Next step -- VMT (Score 3, Insightful) 114 114

The problem with license plate readers is that there are only so many cameras out there. How can they know where everybody was all the time?

The answer is the Vehicles Miles Traveled tax. Many states and the federal gov't have proposed over and over that all cars have GPS trackers in them that tax them on how many miles they drive. They say "the problem is cars are more efficient, so we don't make as much money." (Can't you just raise the rate then? wtf?) or that this is "more fair", everybody is charged the same amount for how far they drive; as opposed to how much gas they use and how much carbon they emit.

But, come on, the real reason is almost certainly to track where everybody went, all the time. If there is anything the Snowden revelations have demonstrated, it's that if there is any possible way to capture data on people, the government is going to do it. Anything you can imagine, and many things that you could never have imagined, are being done. If you want to believe that a GPS tracker that hooks up to a gas pump only sends one bit of information, well, I suppose you deserve what you get.

Comment Granted OffTopic, but can BootCamp do Linux? (Score 1) 209 209

I tried for a day to get Linux installed on my Mac. I thought Boot Camp would be perfect; it repartitioned the drive nicely, but I couldn't get Linux to load. I couldn't delete the Windows partition, couldn't remake it as a Linux partition. Eventually gave up. Is there a way to do this?

Comment Re:projecting UV images from below liquid resin? (Score 1) 95 95

Thank you. I just couldn't understand it; although clearly the clues were there and you interpreted them correctly.

So the UV light goes through the bottom window, through the oxygen-rich zone that will not polymerize. When the light gets through that zone, it polymerizes the resin. The polymerized resin must block the light from going deeper into the liquid resin.

If you have a thick part, though, I wonder if this could work? New unpolymerized resin would have to flow into the gap between the hardened part and the window, and this 'dead zone' is only microns thick. Now, I do believe that most 3D printed parts aren't solid blocks; but this could be a limitation.

Still, looks quite cool. I am sure that I'm not alone wanting to build stuff with it!

Comment How can this work? Even with 4000 satellites? (Score 2) 115 115

The area of the earth is 4,000^2xpi square miles, so even with 4,000 satellites there is one for every 12,000 square miles. OK, perhaps the very high latitudes don't need to be covered, and you can get that down to 10,000 square miles. For the United States, the average population density means that on average, you'd have 500,000 people covered by one satellite. Europe, Japan, China, Indonesia, and many other countries or regions have significantly higher population density. For cities, this is just a non-starter.

Now, Musk is not a stupid guy, but I just can't see how this works.

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