Energy From Vibrations 529
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?
"
"Young lady, in this house we obey the laws... (Score:2, Insightful)
The article is (I assume) about energy recovery/scavenging, but the article poster just invented perpetual motion, arguing that the vibrator from the ringer could power the cellphone.
HA.
Re:"Young lady, in this house we obey the laws... (Score:1, Insightful)
a bugg
Re:"Young lady, in this house we obey the laws... (Score:2, Insightful)
Yes, the submitter did say that, but went on to speculate that you'd be wanting to get more calls in order to keep your battery charged, so the overall tone was that as long as you kept getting calls, you'd keep your battery charged.
I am not a physicist, but... (Score:2, Insightful)
Re:"Young lady, in this house we obey the laws... (Score:3, Insightful)
Nah, they were clearly delusional.
Re:Remember Friction? (Score:2, Insightful)
Re:Someone's got to say it... (Score:3, Insightful)
Re:"Young lady, in this house we obey the laws... (Score:5, Insightful)
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.
To all naysayers (Score:5, Insightful)
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.
Re:This could be sweet. (Score:4, Insightful)
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.
Re:Conservation of energy (Score:2, Insightful)
So, if you want to make you vibrating phone last longer, spend less energy making vibrations. The gains from this are far greater than any attempt (no matter how you do it) to recapture the energy.
As another poster said, one useful application would be making the phone capable of charging itself if placed on an external source of energy (such as some loud or vibrating surface).
Re:Thermodynamics (Score:2, Insightful)
Seems you could use the same theory, have the pad vibrate ever so slightly, and capture that energy (much in the way the kinetic wrist-watches mentioned elsewhere do) to charge the devices.
Then again, maybe it would just vibrate everything onto the floor.
Re:"Young lady, in this house we obey the laws... (Score:3, Insightful)
Re:This could be sweet. (Score:0, Insightful)
Re:"Young lady, in this house we obey the laws... (Score:1, Insightful)
No free lunch (Score:3, Insightful)
The trick is to identify sources of vibration that inherently useful. Could you, for instance, harness vibration from an internal combustion engine? If so, you would improve the entire system dramatically by eliminating the need for an alternator and reducing unwanted vibration with something more productive than pneumatics, hydraulics, rubber bumpers and foam.
Vibration is a profoundly complex matter. People devote entire careers to understanding and mitigating vibration. I have an engine in my car that has two "balance shafts". One of these shafts spins at 2x the speed of the crankshaft. I believe this is because a 90 deg V6 is an inherently unbalanced design. Yet engineers go to extraordinary lengths to mitigate this because the net benefits of the complete package outweigh the cost of creating a lot of additional rotating mass.
Car engine (Score:2, Insightful)
Now we can tap in a car engine's vibrations to recharge the battery...
Make it more efficient, and it can dampen the vibrations enough to even replace the muffler!
Perpetual Motion aside... (Score:3, Insightful)
Vibration can also easily be produced from renewable resources, or as a byproduct of other processes. Imagine on the street above a subway, having a "charging table" which vibrated every few minutes as the train passed under it. Or a wind-powered system to do the same thing.
Re:"Young lady, in this house we obey the laws... (Score:2, Insightful)
conservation of engergy? (Score:3, Insightful)
Now go sit in the corner and think about what you are about to say before it comes out of your mouth.
New Failure Modes (Score:5, Insightful)
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.
Re:The truth about perpetual motion (Score:5, Insightful)
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.
Re:self recharging key fob (Score:2, Insightful)
Re:This could be sweet. (Score:5, Insightful)
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.
Windmills in the ducts (Score:4, Insightful)
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.
Err, you aint gonna get no free energy. (Score:1, Insightful)
If anybody has found a way to gain more energy
back from an action than what you put in, Id love to hear about it.
(Outside of thermonuclear reactions and the harvesting of potential energy)
Re:"Young lady, in this house we obey the laws... (Score:2, Insightful)
I wasn't trying to disagree with thermodynamics: I understand it quite well.
Trying to use the vibrations generated by the phone, to recharge the battery that
was drained to create the motions is a losing battle.
It's much easier to turn of the vibrator and not worry about it.
Re:Wow! (Score:3, Insightful)
Plus, if you're collecting energy from the phone's vibration, you're going to make it vibrate less. The value of the system is to collect energy from unwanted or wasted movement. The vibration of a cell phone is a desired use of energy.
i guess rules of physics still don't apply here... (Score:3, Insightful)
the energy required to make the cell phone vibrate would be more than it could recoup from charging from vibrations. there is no perpetual cellphone.
Re:This could be sweet. (Score:3, Insightful)
They use about 1/4th as much power (they're still pretty inefficient as far as flourescent bulbs go) and last much longer.
And best of all, they're available NOW! (go get a 4 pack at Home Depot for $7.99.)
Re:Obligatory Quote (Score:4, Insightful)
IN THIS HOUSE WE OBEY THE LAWS OF THERMODYNAMICS (Score:3, Insightful)