We lose only 5% of our electricity in transmission in the USA, and it could be even lower if we just stepped the voltage up further.
According to wikipedia the actual figures are closer to 7%.
... but cost isn't just about lost electricity. It also costs money to build and maintain a large electrical grid. We have one already, but it could be much larger. And then there's the environmental costs of putting up lots of high voltage lines across what used to be forest. And they're ugly too.
But if some source of electricity were to appear in the middle of the country that provide enough power to power the entire country cheaply (alien spacecraft? Zero-point module? fusion plant? magic?), the infrastructure to distribute it would pop up very quickly. It would be expensive, but over time it would probably be cheaper than what we do now.
The fire department was afraid of using the `jaws of life' on a hybrid lest they cut into 400v wires... a nuclear reactor would probably concern them even more. And what if you had an accident and broke the containment on the reactor?
Small nuclear reactors are used in deep space probes and remote monitoring outposts (though I'm not sure the USSR/Russia still uses them), and while these would fit in a car, they wouldn't provide anywhere near enough power to power a car. These are designed to last for a long time, not provide a lot of power.
It looks like we're going to have to power our cars either with some sort of chemical fuel (gasoline, natural gas, hydrogen, etc.), or batteries (or ultracapacitators, if they can be improved), for the time being. Mr Fusion is still a few years off.
Side note -- solar panels might work, as long as the sun was shining and people are OK with going a whole lot slower. Solar panels on top of a car can't provide anywhere near enough power to make it go 55 mph, but solar panels on top of a bicycle (or tricycle) could provide enough power to go 15 mph or so under ideal conditions.
Most likely, your home is powered by the electrical grid, which gets power from wind, hydro... coal, perhaps some nuclear, natural gas, etc.
It's nice that you checked a box on your bill that says `I want green power!' and perhaps you paid a little extra to be able to say that, but the reality is that checking this box didn't actually change where your power came from.
I'm not saying that it's a bad thing, but it's not quite what people claim.
Ok, but somebody in your front yard is a curiousity. Might be somebody lost, might be lots of other things. (And yes, he might be on his way to your living room, but that's unlikely.)
A stranger in your living room is a totally different situation, one that is probably best met with a call to the police (though the response for rural folk might be a lot slower) and a gun, or perhaps sneaking out the back door to get help.
Somebody in my front yard, unless he's actively breaking my windows or kicking in my door, I'm not likely to freak out about, at least not at first.
To you city folks who think this is wrong, how would you like to wake up and find me in your living room?
I realize that you're trying to make an analogy, but I was under the impression that `rural folk' lived in houses too. So the proper analogy for somebody on your property would be somebody in my front yard. Or, if fences were jumped, my back yard. If I found somebody in my front yard, I'd probably ignore them unless they hung around, in which case I'd ask them to leave. My back yard, I'd yell at them to leave. My living room, the police would be called and I'd have my gun loaded and ready to shoot.
I'm guessing you'd be ready to shoot somebody in your living room too. But not just on your property.
SuperDuperCrete sounds a lot like either balonium or
unobtanium.
Sod probably has more bounce than you give it credit for. Sand is the thing to think about -- lots of give, zero bounce. Any `bounce' left is energy that this system cannot extract.
Ultimately, it is all about numbers, as most things are. But putting in real world numbers for how such a system might work, and calculating how much energy you might extract, it's far from practical, even assuming 100% efficiency -- and you're not going to get better than 100% efficiency.
Such a system might have some usefulness if you only needed a small amount of energy and you had no access to the electrical grid. If all you needed was 1/100th of a watt, a small panel that people would walk over occasionally, along with a few ultracapacitators to store energy when nobody is walking on it, might do it. But trying to compete with the electrical grid? Not practical. Perhaps if energy cost 100x as much, then it would be practical (but solar power becomes very practical long before we'd reach that point.)
The ultimate in human powered machines is probably the bicycle. A reasonably in shape person can generate about 100 watts of power for a few hours on a bike. At 20 cents/kwHr, that's $0.02/hr for your hard work -- that can't compete with the electrical grid, not even close.
(Bikes work not because they make people work, but because they require so little power compared to a car (mostly because power required is poportional to the cube of the speed, and bikes are relatively slow.) As fossil fuel prices go up and up, I expect that we'll see more and more bicycles on the roads, and for cases where the people can't pedal hard enough, we'll see more electric bicycles -- they're actually practical today, as opposed to electric cars which are somewhat iffy.)
You're right that all surfaces move to some degree, and some move more than others. Where you're wrong is that most surfaces return most of that energy when they bounce back. Sure, there's some energy lost, but in most cases most of it's returned.
Sand is a case where most of that energy is not returned, and it's very tiring to walk on sand. Ditto for non-packed snow.
Ultimately, it's not going to be practical.
Doing some simple math, let's say that you have 10 180 lb people walking on your special floor, one step per second. Let's suppose that the floor extracts 1 mm worth of energy on each step (a small amount, hopefully not enough to make walking too tiring.) Assuming that everything is 100% efficient, these 10 people will generate 8 watts of power. Assuming 20 cents/kilowatt*hr, that's 28 cents per week (assuming ten people walking 24/7.) Sure, you can make it 100x as big, with 1000 people walking 24/7, but then that's only $28 per week generated, for a system that probably requires several times that much in maintenance every day. Now, you could replace 1 mm with 1 cm -- that would make your 1000 people generate $280/week worth of power, but 1 cm is enough to make people really hate walking on this, because it would feel like walking on sand.
I didn't say that the cost of solar panels was zero. You snipped too much. Also note that the parent post said approximately that `there is no such thing as free energy', which I was disagreeing with to some degree.
Would we just toss aside General Relativity, never to see it again, because we don't want to be associated with the author? This is the worst analogy I've seen today. Granted, it's still early, but even so, you're likely to win the `worst analogy of the day' award. Congratulations!
Why is it a bad analogy, you might ask? Because General Relativity was Einstein's attempt to explain an aspect of the universe. No matter how much we might hate him, that won't change the universe, and if he explained it well, then we're stuck with that.
ReiserFS is something built by man. If we don't like it, we build something new. It might have some similarities, but would be different in other ways. Also, computer software needs supporting -- as bugs and security holes are found, they need fixing. Reiser presumably cannot do this from prison, and he was the driving force behind ReiserFS.
In any event, ReiserFS was dead when he was convicted -- producing a body won't make it more dead.
The smaller the deflection, the less power generated. If it's hundredths of a millimeter, then you'd be right -- nobody would notice. But on the other hand, the energy generated would be insignificant.
I may agree that extracting energy from humans like this isn't practical, but your figures are wrong.
A world-class bike sprinter can put out 1500-2000 watts for a short period of time, perhaps a minute or so. Lance Armstrong can put out about 500 watts for 30 minutes or so, and a somewhat lesser amount for many hours.
I'm a pretty weak pedaler, but I can put out about 100 watts for an hour or so without too much trouble.
Energy from the sun is approximately free, especially when you put your solar panels on top of building and such rather than in fields... but I digress. (I said approximately -- the solar panels are not free, and neither are any other components or their maintenance.)
But as for free energy -- this is not it. By putting generators in the ground that are moved by people walking on them, it will make it harder to walk. I don't know the specifics, but I'm guessing that parts of the floor will move up and down a little as people walk on it, probably a few milimeters. It might be somewhat akin to walking on sand -- and I have to wonder what it would do to a wheelchair.
This might be practical if you're in a remote location where electrical power is unavailable and you only need a little -- but beyond that, the solution seems worse than the problem. (And really, solar power is more practical for remote areas where you need only a little power.)
Nicely done -- you nailed it. Though I'd emphasize a little more what a pain selinux can be for a general-use system. The learning curve is relatively steep, and like many security measures, it often does get in the way of doing work, especially when you don't really understand it yet. And so yes, it does tend to get turned off.
You can disable images in most browsers if needed.
Though I doubt it'll be needed -- most browsers will cache images, and the little icons won't change often. So they'll be downloaded once, and not again unless they change.
Agreed, `get used to a text client' is a silly solution...
Actually, I just realized what the perfect solution is -- webmail.
It has no problems with large attachments (download them if you want, not if you don't) and is easy to use, doesn't require that you know how to use a shell or a text mail reader, and can be reasonably fast even over a dialup as long as they don't fill it with too much javascript and graphical crud.
Really, if all you want to do is look at web pages and get mail, dialup is sufficient. You won't be watching movies online, and things will be slow, but most sites should be tolerable.
While a text-only mail client seems to make sense, it doesn't make all that much. Attached photos will pose a problem regardless whether or not your email client can process them, and a GUI mail client like Thunderbird poses no more or less traffic than a text-based one like PINE.
Agreed, `get used to a text client' is a silly solution, but it does solve the problem in one case -- if you run it on a shell box that you ssh into over the dialup. If you run your text mail client on your home box, it's not going to be any faster than a GUI client (imap or pop3 doesn't care what client uses it) but if you run it remotely, then large attachments aren't a problem (unless you actually want to view them, of course, in which case you'll have to transfer them to your home box separately.)
I mean, how often does anybody actually survive a plane crash? It depends on how you define crash. If you hit hard and break your landing gear and prop, is that a crash? Flip a Piper Cub over at 10 mph? Neither `crash' is likely to kill people.
In any event, nobody knew if Fossett crashed. At the time, the hope was that he'd landed somewhere and was having a hard time getting somebody to find him (though his ELT should prevent that.)
Ethically, the family would probably be the ones to make that decision. But of course you have to be OK with it too if you're doing the work. It might be wise to talk to a lawyer and make *sure* there's no legal issues for you (ethical issues make you feel bad. legal issues put you in jail or debt.)
Practically, the laptop should be easy to crack (you have physical access) unless the drive is encrypted.
As for myspace, MSN, etc -- if the laptop has passwords or valid cookies saved by the browser, and you don't need a password to access them, that's easy. Otherwise, it's going to be very hard. myspace and others are unlikely to let you in without some sort of legal force like a subpoena. And this is exactly as it should be -- if it's easy, people will abuse it to crack the accounts of the living.
Actually, some fools use the same passwords on lots of web sites, and you can get some sites to mail you your password, so if you can get access to that mail...
In any event, it sounds like the family has a good reason to want access to this stuff, and the guy is dead, so I wouldn't have an ethical problem with it. Well, I'm assuming that he was on good terms with his family -- if he hated his family, that might be a different case...
I guess if you want to debate about what an OS actually is, which does seem to be a pretty popular religious debate. Though it's a bit sillier than most -- vi vs. emacs, Mac vs. PC, Catholics vs. Protestants -- at least these debates MATTER somehow. Is MS-DOS a true OS? Who gives a rats ass? It loaded up Commander Keen, so it was good enough for me!
Either way, when MS-DOS first came out, I don't recall anybody claiming that it wasn't an operating system.
Slashdot Mirror
Hell, there have been some superconductors found that work at 70 degrees!
Perhaps rather than `get a real unit', just give a unit, real or not.
But if some source of electricity were to appear in the middle of the country that provide enough power to power the entire country cheaply (alien spacecraft? Zero-point module? fusion plant? magic?), the infrastructure to distribute it would pop up very quickly. It would be expensive, but over time it would probably be cheaper than what we do now.
The fire department was afraid of using the `jaws of life' on a hybrid lest they cut into 400v wires
Small nuclear reactors are used in deep space probes and remote monitoring outposts (though I'm not sure the USSR/Russia still uses them), and while these would fit in a car, they wouldn't provide anywhere near enough power to power a car. These are designed to last for a long time, not provide a lot of power.
It looks like we're going to have to power our cars either with some sort of chemical fuel (gasoline, natural gas, hydrogen, etc.), or batteries (or ultracapacitators, if they can be improved), for the time being. Mr Fusion is still a few years off.
Side note -- solar panels might work, as long as the sun was shining and people are OK with going a whole lot slower. Solar panels on top of a car can't provide anywhere near enough power to make it go 55 mph, but solar panels on top of a bicycle (or tricycle) could provide enough power to go 15 mph or so under ideal conditions.
It's nice that you checked a box on your bill that says `I want green power!' and perhaps you paid a little extra to be able to say that, but the reality is that checking this box didn't actually change where your power came from.
I'm not saying that it's a bad thing, but it's not quite what people claim.
My guess is that people will keep burying nuclear waste (when they can't re-use it) for a while yet.
A stranger in your living room is a totally different situation, one that is probably best met with a call to the police (though the response for rural folk might be a lot slower) and a gun, or perhaps sneaking out the back door to get help.
Somebody in my front yard, unless he's actively breaking my windows or kicking in my door, I'm not likely to freak out about, at least not at first.
The analogy was inappropriate.
I'm guessing you'd be ready to shoot somebody in your living room too. But not just on your property.
Sod probably has more bounce than you give it credit for. Sand is the thing to think about -- lots of give, zero bounce. Any `bounce' left is energy that this system cannot extract.
Ultimately, it is all about numbers, as most things are. But putting in real world numbers for how such a system might work, and calculating how much energy you might extract, it's far from practical, even assuming 100% efficiency -- and you're not going to get better than 100% efficiency.
Such a system might have some usefulness if you only needed a small amount of energy and you had no access to the electrical grid. If all you needed was 1/100th of a watt, a small panel that people would walk over occasionally, along with a few ultracapacitators to store energy when nobody is walking on it, might do it. But trying to compete with the electrical grid? Not practical. Perhaps if energy cost 100x as much, then it would be practical (but solar power becomes very practical long before we'd reach that point.)
The ultimate in human powered machines is probably the bicycle. A reasonably in shape person can generate about 100 watts of power for a few hours on a bike. At 20 cents/kwHr, that's $0.02/hr for your hard work -- that can't compete with the electrical grid, not even close.
(Bikes work not because they make people work, but because they require so little power compared to a car (mostly because power required is poportional to the cube of the speed, and bikes are relatively slow.) As fossil fuel prices go up and up, I expect that we'll see more and more bicycles on the roads, and for cases where the people can't pedal hard enough, we'll see more electric bicycles -- they're actually practical today, as opposed to electric cars which are somewhat iffy.)
You're right that all surfaces move to some degree, and some move more than others. Where you're wrong is that most surfaces return most of that energy when they bounce back. Sure, there's some energy lost, but in most cases most of it's returned.
Sand is a case where most of that energy is not returned, and it's very tiring to walk on sand. Ditto for non-packed snow.
Ultimately, it's not going to be practical.
Doing some simple math, let's say that you have 10 180 lb people walking on your special floor, one step per second. Let's suppose that the floor extracts 1 mm worth of energy on each step (a small amount, hopefully not enough to make walking too tiring.) Assuming that everything is 100% efficient, these 10 people will generate 8 watts of power. Assuming 20 cents/kilowatt*hr, that's 28 cents per week (assuming ten people walking 24/7.) Sure, you can make it 100x as big, with 1000 people walking 24/7, but then that's only $28 per week generated, for a system that probably requires several times that much in maintenance every day. Now, you could replace 1 mm with 1 cm -- that would make your 1000 people generate $280/week worth of power, but 1 cm is enough to make people really hate walking on this, because it would feel like walking on sand.
I didn't say that the cost of solar panels was zero. You snipped too much. Also note that the parent post said approximately that `there is no such thing as free energy', which I was disagreeing with to some degree.
If you make walking harder, fewer people will walk.
He might have a hard time killing her in a fair fight, but I'm guessing that most premeditated murders don't involve a fair fight.
Either way, I think she's safe.
Why is it a bad analogy, you might ask? Because General Relativity was Einstein's attempt to explain an aspect of the universe. No matter how much we might hate him, that won't change the universe, and if he explained it well, then we're stuck with that.
ReiserFS is something built by man. If we don't like it, we build something new. It might have some similarities, but would be different in other ways. Also, computer software needs supporting -- as bugs and security holes are found, they need fixing. Reiser presumably cannot do this from prison, and he was the driving force behind ReiserFS.
In any event, ReiserFS was dead when he was convicted -- producing a body won't make it more dead.
The smaller the deflection, the less power generated. If it's hundredths of a millimeter, then you'd be right -- nobody would notice. But on the other hand, the energy generated would be insignificant.
A world-class bike sprinter can put out 1500-2000 watts for a short period of time, perhaps a minute or so. Lance Armstrong can put out about 500 watts for 30 minutes or so, and a somewhat lesser amount for many hours.
I'm a pretty weak pedaler, but I can put out about 100 watts for an hour or so without too much trouble.
But as for free energy -- this is not it. By putting generators in the ground that are moved by people walking on them, it will make it harder to walk. I don't know the specifics, but I'm guessing that parts of the floor will move up and down a little as people walk on it, probably a few milimeters. It might be somewhat akin to walking on sand -- and I have to wonder what it would do to a wheelchair.
This might be practical if you're in a remote location where electrical power is unavailable and you only need a little -- but beyond that, the solution seems worse than the problem. (And really, solar power is more practical for remote areas where you need only a little power.)
By `normally' you mean `sometimes'. It works sometimes. Not most of the time or even half of the time. But it's certainly worth a try.
Nicely done -- you nailed it. Though I'd emphasize a little more what a pain selinux can be for a general-use system. The learning curve is relatively steep, and like many security measures, it often does get in the way of doing work, especially when you don't really understand it yet. And so yes, it does tend to get turned off.
Though I doubt it'll be needed -- most browsers will cache images, and the little icons won't change often. So they'll be downloaded once, and not again unless they change.
It has no problems with large attachments (download them if you want, not if you don't) and is easy to use, doesn't require that you know how to use a shell or a text mail reader, and can be reasonably fast even over a dialup as long as they don't fill it with too much javascript and graphical crud.
Really, if all you want to do is look at web pages and get mail, dialup is sufficient. You won't be watching movies online, and things will be slow, but most sites should be tolerable.
Yes,but it's not actually robbery.
In any event, nobody knew if Fossett crashed. At the time, the hope was that he'd landed somewhere and was having a hard time getting somebody to find him (though his ELT should prevent that.)
Practically, the laptop should be easy to crack (you have physical access) unless the drive is encrypted.
As for myspace, MSN, etc -- if the laptop has passwords or valid cookies saved by the browser, and you don't need a password to access them, that's easy. Otherwise, it's going to be very hard. myspace and others are unlikely to let you in without some sort of legal force like a subpoena. And this is exactly as it should be -- if it's easy, people will abuse it to crack the accounts of the living.
Actually, some fools use the same passwords on lots of web sites, and you can get some sites to mail you your password, so if you can get access to that mail ...
In any event, it sounds like the family has a good reason to want access to this stuff, and the guy is dead, so I wouldn't have an ethical problem with it. Well, I'm assuming that he was on good terms with his family -- if he hated his family, that might be a different case. ..
Either way, when MS-DOS first came out, I don't recall anybody claiming that it wasn't an operating system.