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Energy From Vibrations
JN writes "Now here's a nifty invention. What started off as a Small Business Innovation Research grant from the Navy to a MIT professor has turned out to become a great mechanism that harnesses running machines' minute vibrations into energy. The possibilities are limitless. Aside from the obvious, imagine the ultimate cellphone - one that charges the battery every time it rings/vibrates, hence promising extended talktimes, and giving operators all the more reasons to get their customers to use their devices. How cool is that? Do I see 3G applications with a vibrate() call mandatory every couple minutes?
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The patent is certainly intended to cover large scale industrial equipment, not mobile phones. In that case, not only would you get excess electricity, but the very act of harnessing that power would also serve to quiet them -- a double bonus.
Hemos is like a lot of sci-fi fans: he thinks technology is cool, but he hasn't bothered to understand the science it's based on.
The vibration of a cell phone is not wasted. It is intentional. To pick up energy from the vibration would be to damp it, then you'd have to vibrate more to get the same alerting effect.
Even if you could get power from the vibration, it would mean that the vibration (which is intentionally selected) is unwanted, or that you would have to crank up the power going into the vibration to compensate.
This supposed energy collector is meant to pick up wasted, unwanted vibrations from engines, ventilation ducts, etc. Not from intentional vibrations.
Infuriate left and right
I know you're joking, but mechanical vibrations that you can't do anything to prevent are probably the best application of this technology.
Remember conservation of energy and thermodynamics... you're not going to get 'free' energy by strapping this to a buzzing, vibrating machine. You might regain a tiny fraction of the energy which the machine is losing (wasting) through its inefficiency, but in that case, you'd probably be better off replacing or repairing the machine to be more efficient.
The applications for this technology are narrow, like powering (small) things in inaccessible areas, like ventilation systems. You're not going to power your factory lights from the vibrations from your machining centers, but you could probably pay your light bill (in the long term) from the savings from replacing or upgrading old, worn out, inefficient machines.
haven't you ever heard of conservation of energy or entropy? Everytime the phone rings, some energy would be used and some of the might be regained, but not all of it, so rining the phone occaisonally would just be a waste because you wouldn't get all of the energy from each ring back.
Now go sit in the corner and think about what you are about to say before it comes out of your mouth.
Taking over one bit at a time...
Imagine. Your systems are running fine, and suddenly half of your sensors stop working. Two days later you find out it's because the HVAC man came around and upgraded all the old compressors' parts to run with no vibration ('cuz it increases the life of those machines, you see), and now all your little micropowered machines have stopped working.
It would seem to me depending on a machine to be inefficient (and thus stealing some of its wasted energy) has this equivalent in the software world: depending on a bug or deficiency in the OS to make your application work. Someone's gonna finally think to fix that bug or deficiency.
fifth sigma, inc.
perpetual motion is possible! ... Proof? Earth's revolution around the sun, the moon's revolution around the earth etc.
Suggesting that the movement of celestial bodies is "perpetual motion" is ludicrous.
"Perpetual motion" (in the context used here) means that you can extract more energy from a device than you put in - which is clearly impossible.
Even taken literally (ie. that something will continue to move forever), it's still not possible - your examples just show that you don't have a very firm grasp of physics, or knowledge of astronomy or geology.
The earth will not continue revolving around the sun indefinitely. It's gradually slowing down, and will probably be consumed by the sun before it comes to a complete halt.
To paraphrase the parent post's comments:
A cell phone will use more energy to create the vibration than it will be able to regain from that vibration.
Due to the laws of thermodynamics and energy,(particularly the law that energy can neither be created nor destroyed), the device that generates energy from vibration would then (by definition) have to absorb some of the vibration's energy. Therefore, in order for this mechanism to "produce" any amount of valuable energy, the source (the cell phone) would have to increase its vibration. However, it will always be the case that the cell phone uses more energy than it gains back (otherwise the phone wouldn't vibrate). Therefore, it would be more condusive of the cell phone to focus its energy on notifying its owner of an incoming call, and do so in the most efficient way.
Basically, (as stated in the parent post) this invention at MIT doesn't do much for the cell phone industry. Cell phones would be better off being more efficient with the energy they have rather than trying to regain some of the energy expelled while producing environmental feedback.
What about small windmills in the ducts?
Wouldn't generate much power, but it might be enough to keep a battery-powered sensor charged.
It'd create some drag in the duct, but a lot of ducts are large enough that it might not matter.
It's too bad that you couldn't electrically charge the duct and get power from the differential between the duct and ground.
Always, as long as there is a remote possibility of it applying to the subject. Sometimes even that isn't a necessity.