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Comment Re:This simply means we're succeeding. (Score 1) 221

Yeah, I looked at the arithmetic and yeah, the arithmetic is sketchy (if 22% cells aren't already sketchy for that price). But yes, they do cover the doors, the rear, basically all non-transparent surfaces with cells. Other neglected things are what happens if you park under trees, in a forest of tall buildings, in parking garages. It's never going to be 7.5 m^2 x 0.22 x whatever you want to claim for mean daily integrated flux through a perpendicular surface (200 to 300 W/m^2 if I recall correctly).

It's also not clear how much of a "real car" they have in mind. Is it an ELF with solar cells on all surfaces? The ELF now looks more like a car with glossy hard sides than it used to, and they now seem to come with a 100W solar panel on the roof, allowing one to accumulate as much as a KW-H over a whole day. Since it comes with a 500+ W-H battery, it actually could fully recharge over a day in the sun. This gives it a range of around 15 to 18 miles no pedalling on flat ground. Obviously if you add battery, you can add range, but you probably can't fully recharge with only sun unless you add more panels.

The ELF is not vaporware -- I live in Durham and see these all the time on the roads (they cost $6000 to $9000 depending on how tricked out you get them). Adding solar capacity is actually pretty easy, as is adding battery capacity. One could probably accessorize to 30 miles a day and still manage a full recharge on its rated mileage of 34 mpkwh (add another 500 W-H battery and another 100 W panel with some sort of hinge that you can tilt up to horizontal-ish when you park). Actually, this isn't bad at all, and would probably do me just fine on my commute, leaves the money in my home town, and gives me the option of pedalling to get SOME exercise on the run without having to pedal up all the hills on muscle alone (hot and sweaty, at least, during the summer). Pedalling also extends the range, obviously.

The catch is that it isn't technically a car, and cannot go 45 to 50 mph on the one road I would HAVE to drive on that is 45 to 50 mph if you want to go WITH the traffic, and it is even more of a road obstacle than a bike if you are traveling under road speed. Which makes it still quite dangerous, although maybe a hair less so than a bike (at least one person I know of has been killed on the road I have to ride in on in the last year on a bike).

So, can one imagine taking the working ELF design, bumping its internal energy storage to 14.5 KW-H, bumping its solar capacity to (say) 400 to 600 W, (say, 2400 KW-H/day) increasing its top speed to street legal (say 55 mph for mostly in town driving), sticking with polycarbonate sides but increasing seating to four in more of a car-like configuration, and still maintaining at least 12 m/KWH, needed to get 30 m in a day's charge (with no pedals)?

It's not completely insane. Doubling speed increases power required by around a factor of 8 but takes only 1/2 the time to go the distance, so it needs 4 times as much energy IF one assumes energy is dominated at that point by quadratic drag. Well, we've quadrupled incoming power (relative to 30 miles/day), increased stored power by a much larger factor than necessary, so in principle if we haven't added TOO much weight or MUCH less efficient motors, we are at least in the ballpark. Can we do this by no more than doubling the high end cost? Again, maybe, hard to say. We'd save some by not having pedals and all the dual power source gearing, we'd spend it and more on the extra batteries, solar capacity, and the 4+x more powerful motor. But it might be doable. ELF might make it there on its own as it has the substantial advantage of building and selling actual vehicles right now that already work pretty well as in-town commuters, better/safer where the speed limit is 35 mph and under, not so well where it is 35 mph and over. If they are and remain profitable as they grow, they could end up bringing out higher end, closer to car vehicles within a year or two even without any competitive incentive, and in Europe the cost profile may or may not be advantageous for a local competitor to develop.

ANY real improvement in several critical components -- motor efficiency, energy recovery while braking, active solar charging, energy storage -- could make this general approach into a COST efficient alternative to auto-based in-town or in-city commuting. Cheaper than a car, check. Self-solar-fueling or nearly so for the expected daily driving range, check. Low maintenance (compared to a car!), probably check. Made of materials that will last without rusting out or getting brittle (and cheap to replace), maybe check, dunno. Insurance? Dunno. Safe? Probably not as safe as a car, conceivably safer than a bike (if they build them truly street-legal at 55 mph). Quite aside from "saving the planet for the whales", I've thought about them as ways of saving the $100-150 I have to spend per week on fuel, maintenance, insurance, and depreciation to do my daily commute in a car whose capital cost was over $16K used. Spend less than $16K new, save (say) $1200/year, and be insulated from fuel supply chain interruptions and price hikes? Sounds like a good bet to me, if it is safe enough to drive without quadrupling the risk of an accident during rush hour.


Comment Re:I would try it. (Score 1) 118

Been there, done that. Basically had to go to the max dose of oxycontin just to take the edge off the pain.

This page you can see some pictures of the procedure and instruments people used on kidney stones in the 1600s. It seems unimaginable that anyone would subject themselves to that -- without anesthetic -- unless you've actually experienced it.

Comment Re:This simply means we're succeeding. (Score 1) 221

For windmills, you can use vertical axis windmills to avoid slaughtering birds.

Or, you can put cats in hamster-wheel cages that generate electricity. After all, cats kill somewhere between several hundred million and a billion birds a year, almost as many as transparent glass windows kill by enticing birds to bash in their own brains flying into them. According to at least one of the efforts to put names to causes of human-linked bird mortality. Turbines aren't really in the top ten causes. Windows is number one, with cats at number 2, high tension power lines, pesticides, cars, communication towers, and hunting all much higher in total mortality than wind turbines. So if you want to save birds, put some of those ugly little butterfly decals on your windows and don't wash them so often that they are perfectly transparent. Use your neighborhood cats for target practice. Avoid using electricity, don't use chlorinated hydrocarbons and anticholinesterases on your lawn and garden, try not to drive, and go hunting for the human hunters as well as the cat (and even dog) hunters. As many birds are killed every year as fishing by-catch (in nets and with hook and line) as are killed by turbines.

Just to get a little perspective. I have other reasons to dislike turbines as energy sources, one of them being that they are large and ugly and have a poor duty cycle in many locations and have high maintenance costs and take up a lot of room and... but there is no need to throw birds in as a good reason to be hatin'.

Outside of that, I agree. But see the article on New Atlas today -- it alleges that a car that at least charges itself on a daily basis with no external power supply at all is possible and should be commercially available next year, maybe, if the article isn't bullshit. I rather think that it is, but will reserve judgement for the time being.

Comment Re:This simply means we're succeeding. (Score 2) 221

I don't disagree with your math, but an article on NewAtlas TODAY extols a claim from a German company that they are going to build a car with 7.5 m^2 of 22% efficient polycrystalline solar cells covering its flattish surfaces, with a 14.5 kW-H internal battery, that will get at least 30 km/day from normal ambient (unobstructed, sure) sun. Their so-far rendered image of a car looks like a smallish four seater commuter car. They also CLAIM that they will sell this for $14 to $16K USD.

I'm skeptical -- but if the DO manage this, it would make a hell of a car for my in-town driving. Basically buy it and then use it without fuel for the rest of its useful life, because I don't drive 30 km/day on average, even including runs to stores as well as work. I'm not sure it would be a good "only car", but it would sure take the pressure off of my 4Runner (needed to pull a boat and for trips but overkill for daily commuting).

The point being that there may be "specialty cars" that can actually function as solar cars for limited length commutes. The ELF (made in Durham NOW, as opposed to dreaming-ware like the car in the new atlas article) could almost do it, if you could hook it up to a few square meters of panel this efficient, but it isn't really a "car", it is more of an electric enhanced tricycle with a tarp-like cover and a bit of storage. But for $6000, one could add the solar panels and a system to accumulate enough charge at home in a day to keep it charged for standard commutes, if it were really road safe (IMO it's not, quite).


Comment Re:And Yawn! (Score 1) 17

A properly designed system shouldn't be highly dependent upon any kind of persistence layer, although if you follow the provider's example programs you'll tend to spread dependencies through your code. But a smart designer hides that all away deep down in some kind of abstraction.

A demonstration of exactly how little you are dependent on a vendor is probably a very good thing, if you're a big customer. Oh, we'll run *this* part of our product on the other guy's cloud service and boom. It happens. Shows the vendors who's boss.

Comment Re:This is the same state (Score 0) 294

It (HSR) was never going to work, and even if they built it, would lose money, and require more and more Subsidies. The Train was never going to work, it was a payoff to the Unions for their support of Liberal Democrat election campaigns. It was never going to work, because it was already under funded and over budget even before the first train rolled out of the station.

Reality is a bitch to people wearing rose tinted glasses.

The reality is, HyperLoop is much more attractive .. at least in concept.

Comment This,kids, is what it was like back in the day. (Score 2) 92

The developer of this thing has thoughtfully provided a "hello.c" file and cc. Oh, yes, and emacs. So go ahead and type:

cc -o hello hello.c

and marvel at the speed.

This environment is just like my first full-time, non-student programming job. There was no IDE, so we pretty much lived in emacs. I haven't used emacs in decades, but my fingers still remember the key bindings for the commands -- as long as I'm not trying to consciously remember them.

It was on a 68020 running at 16 MHz which delivered a grand total of 2 MIPS at 16 MHz. We shared all that computing power among four programmers, which was luxury because the system was supposed to support 16 users (32 max).

It seems almost inconceivable, but the funny thing is it was really just as fun programming back then as it is now with a supercomputer all to myself. Our office was next to a reservoir, and used to start a compile, wait five minutes for the parsing to catch any syntax error (about 75% of the time), then go for a walk on the 1.5 mile trail around the pond. Then I'd stop in at the convenience store to buy a cup of coffee, and head back to the office, and make would just be finishing up the linking. God forbid you got a link error though. That's why we had time to read the entire Unix manual (all eight sections) cover to cover. Many times.

This has fed my conviction that user perceptions of system speed are as strongly affected by consistency as it is by absolute speed. If you're used to a build taking fifteen seconds,a sudden change to 30 seconds seems unbearable.

Comment Re:Anti-Hillary is not Pro-Trump (Score 1) 851

Robert Byrd can renounce everything he did, but that doesn't negate that he did those things. And I have never seen Donald Trump actually courting racists "Hey KKK, I want your vote". In fact, I have seen him courting black people quite a lot, and there are enough black people who don't believe Clinton's "act" in front of Black people (Fake "black" accent, "hot sauce" comments etc).

"David Duke endorsed me? OK, alright. I disavow, OK?" Trump said, seeking to quickly move on to another question.

Apparently that isn't good enough for you. .

Keep in mind, I am NOT voting for Trump. Gary Johnson for me 100% But the KKK has also endorsed Hillary, and I don't see you protesting her.

Comment Re:I'm just guessing they won't study the fraud (Score 1) 641

Look, this is a prime example of what I'm talking about. It all seems plausible to the poster because he doesn't personally know any scientists. Trying to organize scientist into a vast, disciplined conspiracy is laughable, if you've ever worked with them. They're waaay more likely to be obstreperous free thinkers than they are to be timid conformists.

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