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Is it possibe for a device to be 100% effecient??? Answered

Is it possibe for a device to be 100% effecient???


Ununpenium may be used to give 100% efficiency but it is a predicted property

it really depends on what it is and yes there are some things that are 100% efficent. sorry bad spelling

Not practically 100% efficient... There will lamost always be some power loss in some way. Take, for example, a generator that uses a wheel to generate the power. Some of the power will be lost by heat, due to the friciton. That is my theory though, and it is NOT proven.

Be more specific. If you are asking about a heat engine, then no, a heat engine cannot be 100% thermodynamically efficient. If you are asking about a mechanical operation, then yes, you can have something that is trivially 100% efficient at its task. For example, the paper shredder in my office dutifully shreds every single piece of paper (100%) I give it into bits of confetti. If you are asking about quantum efficiency, such as a photovoltaic cell, then yes, you could theoretically have a device with 100% efficiency, but it would be very difficult to create in reality.

hey kelseymh,

Had an idea...I know its far fetched but I think a near 100% effeiecient solar cell could be achieved. I'll post the articles and you tell me what you think...
http://www.ecogeek.org/content/view/1329/...now obviously most people don't pay attention because this is theoretical simply because there is no way to harness the electricity. But if there could be a way devised you could combine this technology, which aborbs mostly IR light, with this... http://news.softpedia.com/news/Little-Wonder-Boy-Discovers-New-Solar-Cell-Type-93760.shtml ....notice his improvement was in the visible and UV spectrum...if these two were put together and both being in the nanotech region I think it would be possible to create a near 100% absorbant solar cell. Also wanted to show you this....http://www.superconductors.org/265K.htm ... this doesn't negate the third law but doesn't this change the third law of themodynamics a little? You have always been open and honest with me, tell me what you think?

Not so much anymore...You could create an artificial enclosed envirnoment using mirrors(the best kind would obviously be laser mirrors since they have near 100% reflectivity. Place on the inside solar cells and an LED. Connect these two sources with...... (Tl4Ba)Ba2MgCu8O13+, (magnsium and copper) revealed diamagnetic transitions near 267K in five separate magnetization tests and resistive transitions near 265K.....for those not in the know 265 degrees Kelvin is 17 degrees fareinheight. In other words about as cold as your refrigerator freezer section. Superconductivity is now possible at just below freezing, not near zero as the third law of thermodynamics basically states. The only place you could set this up in an natural environment would be the north or south pole, where temperatures normally remain below freezing. However you could prove it in your own house. And as long as the solar cells produce enough energy to effectively run the LED. The exterior of the box would obviously have to be made of metal;1) one to absorb the heat of the LED and 2) to insure the wires stay below 17 degrees fareinheight. Sorry if I seem a little cynical but the three laws of thermodynamics are1) you can't win, 2) the best you can do is break even and 3) the only way to break even is at near zero. (The thid law has been changed a little with this new metal and brought closer to room temp. The second law says it is possible to break even, which I beleive is possible to break even with solar cells and LED's.) This is as near to 100% effeiceincy as you can get...to break even. But as far as 100% effecieincy in reality....hahahahahahahha stop it.

but even when you use a magnet for something (electric motor) it still puts out more energy than it produces ie still looses energy to friction,gravity.

nope, because of friction and air resistance even in outer space theres friction!

Depends on how you define "device". An object which just sits there and does nothing -- consuming no energy, doing no work, completely passive -- might be argued to be 100% efficient, simply because less than 100% of zero is still zero.

 sorry dude but efficency is a measure of how well a device or machine converts energy to other useful forms. if no energy is on the imput then efficency cannot be calculated.


well, a device that is 100% efficient, would need to accomplish these things: first: it would need no energy to work second: it wouldn't produce any waste third: it would lose no energy while working fourth: it would work forever fifth: it wouldn't need another force (a human, by example) to operate it. according to this, the only thing i think can be called 100% efficient is a natural magnet. it doesn't consume energy (it even produces it) it doesn't produce any waste, and so on. there you go, i'd say a magnet is perfect to use!

your first point is wrong because for anything to work energy is needed
energy is sometime defined as the ability to do work  

Natural magnets eventually lose their magnetic field.

technically, I think magnets would break all five of your rules listed.

i don't need to plug in a magnet to make it work, at least that rule is followed, and it does not produce waste. the only thing i'm not sure about is that it works forever...and instead of just saying that you do not agree, explain why you do, please.

A natural magnet isn't a device, it produces a force, like gravity. It's used for storing potential energy, but that energy comes from used energy.

no... energy is always lost in wires in the curcuit, and what ever the device does uses energy. Even in a vacuum energy is lost with mechanical parts, because it has to start moving.

not necessaryly it is impossible for an object to remain startioary in space(vacuum) it will always be attracted and always attract something else 

 true, but any moving parts have friction against each other

i think more energy is lost to a massive object behind the craft that the gravity will oppose the movement of the object and true all mechanical systems loose energy because of friction and this energy is converted to heat and sound and in extreme cases light 

yes, a massive object would cause more energy too be lost

people stop posting things on perpetual motion thats not the question he asked the question is about efficency and it is possible i looked at a simple device the incandicent light bulb, now the first thing people would do is jump down my back saying i talking rubbish but i never said that i wanted the light from it. if thats what i wanted ill get a device thats 5% efficent(i think i never looked at the actual value) but if its the heat i want from it ill get a 95% efficency and i use the light as a bonus that 100%+ or - 0.001 or something like that for the magnetic feild around the conducter but the trick is to figure out how to utilize all the products produced by the device the more you can use the more efficent it will become


9 years ago

Usually not on earth. It is one of the laws of thermodynamics that you can' make a perpetual motion machiene, so you couldn't make one, because of energy losses in heat or something. Mabye light in a vacuum for messaging would work.

they changed the name a perpetual motion device is possible IF and only IF you find a way to keep all the energy you put in stay in.
the devise that people are tring to make in the past like the falling balls are called free energy devices they are impossible because once u take the energy back the machine will start to slow 

According to the "Conservation of energy" theory, energy cannot be created or destroyed, so in theory ALL devices are 100% efficient in that the energy put in will all come out in one form or other,be it heat or sound or actual work, but as far as 100% of the input energy coming out as work done, its very unlikely that a device will ever be made that can do that, too many ways of loosing energy in bad ways.

it all depends this does not apply to nuclear reactions where matter is destroyed to make energy well some of it is and thats why an antimatter device will achieve 100% effiency because all the matter is converted to energy

nope because even if you have some sick peices of technologically advanced equipment there will always be energy loss 
for eg. cooling to absolute 0 will make any conductor a super conducter so no energy should be lost right well no so because as well all kno any conducter carrying a current produces a magnetic feild which takes energy to power but it is possible to have machines near that value like transformers which are 99% efficent and some even higher
there is one device however that is theoritcally might be possible to be a 100% efficent and thats an antimatter bomb
since mass is totally converter to energy the effiency is 100% 

on earth it is impossible to have some thing with no losses or gains it is imposable because there is the loss of heat. the graveyard of energy. at the end of time all energy will turn into heat because there are losses in all systems friction. which gets turned into heat is very hard to collect back into other forms of energy so in conclusion NO

True answer...look up and research Perpetual Motion...non-existing...

maybe it would be possible if you manage to make something move in an environment without friction, it might work forever. because basically kinetic energy becomes heat energy through friction right? so by removing friction, no energy is lost?? im not so sure, comments would be welcome

Yes, that is indeed possible. Do a Google search on the Searl Effect Generator (SEG). It's really intruiging.

If you want a paperweight, then a rock off the floor will "work" usefully for no cost and use no energy. 100% achieved. Trivial answers aside, though, you will never get 100% useful work out of whatever you put in, unless you cheat by using something you aren't paying for to provide the extra. You could use a system of thermal or geothermal devices to get as much power as you want, and then you could argue over whether they are amazingly efficient or amazingly inefficient. On the one hand they are taking only a tiny fraction of the heat of the earth's core (inefficient) but on the other it costs you nothing after set-up and works forever (incredibly effective) Do you count whole-life costs too? Most solar cells use more power to make than they will ever return.


9 years ago

I think that the misconception is that there is a difference between what is desired and what you get - Conservation of energy is the real key, energy cannot be lost and so everything is 100% efficient but not in terms of useful energy, sometimes part of the output is not desirable. I seriously doubt that any device will ever give up all of its energy how you want it to - but the art is to get as much as possible of what you want.

The most obvious 100% efficient device is a space heater. It is designed to turn electrical power into heat. Heat produced away from the heating element (in the power cord, for example) is a bonus, not a loss. Every single joule of energy consumed is converted into heat with absolutely no waste. . This is why I always laugh when politicians say we should turn off heaters to save the environment "Because they're hugely inefficient". Wasteful, maybe, but certainly not inefficient.

Actually, space heaters are not 100% efficient because they produce light as well as heat. Thats why the coils glow - if it was perfectly efficient it would produce no light.

Cultural difference. Where I come from, a "Space Heater" is a flat panel, and doesn't glow. They don't even get that hot, and work sort of like flat radiators. The glowy ones are called "Bar Heaters", because of the glowing bars with the heating filament wrapped around them. Of course, I could argue that since the light (and other non-infrared radiation) is eventually absorbed by whatever it hits, and is re-radiated as infrared, there's no loss there... but that's starting to get ridiculous!

A device's efficiency is just (useful output)/(input needed), both in coherent units (power, energy...) so a resistance heater efficiency is just 100% (1 thermal watt output per each electrical watt you put in).

And, with this definition, an electrical device, as a heat pump, can even have a higher efficiency: for each electrical watt you feed in you can get typically 3 thermal watts of output, that's 300% efficiency (usually stated as COP=3).

And no, you're not breaking thermodynamic laws beacause the two extra watts are "robbed" from the environment outdoors the space you want to heat and, as long as you don't pay for them, they don't have to go in the denominator of the efficiency's formula.

In this sense, we can say a resistance heater is unefficient because, although it's efficiency is 100%, there is an alternative, the heat pump, 3 times as efficient.

I submit gravity as being the nearest to 100% efficient device. It doesn't lose charge over time, and mass will always be preserved bar nuclear reactions. Even in a nuclear reaction the lost mass is turned into energy which is still part of the gravitational system. It's kinda weird question, because every is and isn't 100% efficient. All juice put into something will come out in some form or another First Law of Thermodynamics. So depending on what your inputs and outputs are there may theoretically be a 100% efficient device, but because most of the things we build are made with electricity there wont be. Any electric current has waste in the form of heat, and electric field, most of our juice also gives off electro magnetic radiation.


9 years ago

Hey necropolian - Magnets eventually loose their properties so whilst it looks good its not quite what you think; also think about how it got to be magnetized!!!

oke, oke everyone, i get it. magnets are not perfect. i would go further with atoms, but they have a limited lifetime too. after a very, very, very long time they will vaporize... so an atom is the most near perfect. or no! a vacuum is perfect, because it's actually nothing! but 'nothing' isn't a device, too bad... but an atom is! there you go! a hydrogen atom is the most near perfect thing in this universe!

It's a pity, but no. A device that is 100% efficient would run forever, and even though some devices do run for very very long times, they eventually will lose energy to heat, which will dissipate into the depths of space. This is the debated "heat death" of the universe (but I digress). Even a superconductor has a tiny bit of resistance in it, which will eventually reduce the current running in it until it stops.

It is completely impossible.

We always try to think so. But the third law of thermodynamics begs to differ. In any machine, energy is always lost to heat. So don't believe the junk ads in tabloids. It is a bunch of malarkey. If this law were true, perpetual motion could be achieved. But as I stated before, energy is always lost to heat and / or friction.

This depends, what is the device? In this world, sadly, most devices are not 100% efficient but some machines, tasked to do small tasks that connot be foulded up, are, in theory if not in practice, 100% efficient.

If only, but no. No matter what you do there is a small amount of energy loss even in the best conditions. The third law of thermodynamics states this, http://en.wikipedia.org/wiki/Laws_of_thermodynamics <click here for information.

It's always been a point of dispute, & I think you would have to make up your own mind on this one.

I can think of a way that an object could be 100% thermodynamically efficient at a task, though I would hesitate to call it a "device". If it does absolutely nothing, then work in = work out.

Zero waste.

it might be possible or very close to for example i think a dc powered electrical heater turns all the energy to heat right ?