History Main / PerpetualMotionMachine

*** Perpetual motion machines of the second kind manage to avoid breaking the First Law of Thermodynamics, but do break the Second Law[[note]]Entropy in a closed system always increases over time[[/note]]. Zero-point energy machines generally fall into this, as they do not claim to create energy from ''literal'' nothing, but to exploit energy already in the system...though in doing so, they attempt to run entropy backwards.

* ComicBook/GastonLagaffe once invented one of the "weak" type. It doesn't do much, it just hops around (and gets on his co-workers' nerves).
* GadgeteerGenius [[Characters/XMen80sMembers Forge]] of the ComicBook/XMen dabbled in making one. Never succeeded.
* In [[BonusMaterial Short Circuit #9]] of ComicBook/MegaManArchieComics, Dr Light creates Mariachi, a robot hamster, to generate HamsterWheelPower to charge a battery.

** Poké Balls are able to change in size from a ping-pong ball to a baseball, convert Pokémon and items into energy and store them for indefinite periods of time, simulate a "Pokémon-friendly" environment that is "designed for comfort", communicate with a Trainer's Pokédex to automatically log data on captured species, and even ''teleport'' all without a visible power source. They never need to be charged and have been shown in [[Anime/{{Pokemon}} the anime]] to function perfectly after centuries of neglect. Yet [[ReedRichardsIsUseless this revolutionary level of technology is never shown to be applied to other aspects of life]], as humanity relies on conventional forms of energy despite quite literally having perpetual energy in the palm of their hands.

* On the ''WesternAnimation/GravityFalls'' episode "A Tale of Two Stans", Grunkle Stan's brother [[spoiler:and author of the journals]] made a perpetual motion machine for the science fair, which would have guaranteed him a college grant. Stan accidentally breaks it, which leads to his brother being denied the grant, causing a rift between the two.

* ''WesternAnimation/TheSimpsons'', "The PTA Disbands": Lisa is going crazy while the teachers are on strike and creates a perpetual motion machine. Homer calls a machine a joke, because it keeps going faster and faster, and tells Lisa that no physics law should be broken in his home.
-->'''Homer:''' ''Lisa, get in here! In this house, we obey the laws of thermodynamics!''

* ''WebVideo/CaptainDisillusion'' discusses these in the Series/BeakmansWorld crossover video "BEAKMALUSSION: Free Energy Devices", with Beakman giving a concise, child-friendly explanation of why these simply don't work even in concept, while the Captain debunks several hoaxes and explains how they were faked. By the end of the episode, Beakman is asked if there may come a time where perpetual motion machines might ''ever'' be a possibility, which Beakman acknowledges with one silver lining: in the future, we might end up finding new discoveries that change the entirety of how we perceive physics and how the universe works, which ''could'' help us overcome its limitations to our current knowledge... but he wouldn't hold his breath on it, so for now, they're strictly a thing of fiction.

** [[http://www.scp-wiki.net/scp-2966 SCP-2966]] is a subversion of this trope. It is a toilet paper roll capable of producing infinite amounts of toilet paper. However, unlike many SCP objects, it follows the laws of thermodynamics. To produce the toilet paper, it draws energy from its surrounding area for an energy to mass conversion per E=MC^2. To power produce even 10 sheets of toilet paper a day, the object has to be powered by an entire nuclear power plant providing 2.04×10^17 joules of heat energy solely to SCP 2966. If the reactor fails or too much toilet paper is taken from the device per day, it will instead draw in the heat energy from its surroundings, causing the temperature of a large area to drop to near absolute zero. Inversely, if no toilet is taken, then the object will start converting mass back into energy, causing a huge nuclear explosion. The creator of the device misplaced the square in E=mc^2, meaning he wildly underestimated just how much energy is needed to create a single sheet of toilet paper.

->''"And this 'perpetual motion' machine she made today is a joke -- it just keeps going faster and faster."''[[note]]Meaning, based on this description, it is now an incredibly destructive bomb.[[/note]]
-->-- '''Homer Simpson''', ''WesternAnimation/TheSimpsons'', "[[Recap/TheSimpsonsS6E21ThePTADisbands The PTA Disbands]]"

->"And this 'perpetual motion' machine she made today is a joke -- it just keeps going faster and faster."[[note]]Meaning, based on this description, it is now an incredibly destructive bomb.[[/note]]
-->-- '''Homer Simpson''', ''WesternAnimation/TheSimpsons'', "The PTA Disbands"

* The events of ''Anime/PuellaMagiMadokaMagica'' was based on the attempted creation of such machines. [[spoiler:The incubator are extremely advanced aliens. They want to stop the heat death of the universe, which requires an energy source that can violate the second law of thermodynamics. They figure out how to turn human emotions of pain and misery into an energy source, by turning human girls into magical girls, who then turn into witches, which are in turn hunted by magical girls for the energy collection.]]

* The GadgeteerGenius [[Characters/XMen80sMembers Forge]] dabbled in making one. Never succeeded.

* In ''Film/BattlefieldEarth'', the planet Psychlo has an atmosphere that spontaneously ignites in the presence of radiation. This means radioactive decay does not naturally occur on the planet, meaning the planet ignores the second law of thermodynamics and is effectively a perpetual motion machine.
** In the book, Psychlo's atmosphere has the same implausible property. But, there, it's stated that the Psychlos are actually from a different universe with different physical laws.

* In the second ''Literature/JimButton'' book by Creator/MichaelEnde, the protagonists invent it. Essentially, their version is based on a magnet which you can switch on and off, which pulls their locomotive.
** Violating the Law of Conservation of Momentum as well.
* Discussed in ''Literature/{{Komarr}}''. One of the physicists Miles calls in to consult determines that the device he's asking her about ''looks'' like a perpetual motion machine. Since she's a competent physicist who doesn't believe in such things, she concludes that it must be drawing energy from the deep structure of the wormholes it gets pointed at -- because there's nowhere else it could be coming from.

* An 8th grade student in Yevgeni Veltistov's ''The New Adventures of Elektronic'' claims to have created a small device that causes a little light bulb to light up and never go off after you wind the crank once. When the titular android character is asked if such a thing is possible, he simply says that he doesn't know, but that the device doesn't have any moving parts (except, obviously, the crank). The device is put on a shelf in the classroom and forgotten. It's mentioned that it worked without anyone touching it for weeks, but the little light bulb burned out shortly after. Of course, this is the same book where another student from the same class proved UsefulNotes/FermatsLastTheorem, only to rip up his proof a week later, as he did not want recognition.
* Creator/IsaacAsimov's short story "The Billiard Ball" (reprinted in ''Asimov's Mysteries'') is about a zero-gravity device which, when the zero-g field is established, the field becomes a brightly-glowing cylinder of hard vacuum -- because any air molecules in it lose all proper mass, and thus become incapable of movement at other than the speed of light, so they smash their way out of the field. It's explained by the main scientist character that they get the energy to do this (from nowhere) because in abolishing gravity, the field ''repeals the law of conservation of energy''.
* In Creator/RobertReed's ''An Exaltation of Larks'', time travelers from the [[TheStarsAreGoingOut heat death of the universe]] have been steadily making their way back to the Big Bang (at 15 month intervals) in order to tweak the laws of physics to make the ''entire universe'' a perpetual motion machine - rather than slowly succumbing to entropy, the universe will periodically [[ApocalypseHow collapse]] and then expand again.
* Creator/LeoTolstoy tells a folk story about a Russian peasant who tried to invent this but failed. The man was quite capable of building mills and claimed to even have repaired mills where professional engineers failed, but [[BookDumb lacked education]], and so wouldn't know about the laws of thermodynamics.

* In the Webcomic/GirlGenius novel ''Literature/AgathaHAndTheClockworkPrincess'', it's mentioned in passing that one of the minor Sparks with the circus exhibited a perpetual motion machine, and was utterly mortified when Agatha proved that it needed a small push every ten years to keep going.

* In ''Literature/TheMouseAndHisChild'', the eponymous characters seek to become self-winding, effectively making themselves this. Eventually, someone comes up with the clever idea of connecting two wind-up motors together so that they wind each other. Despite this being a book about [[LivingToys sentient wind-up toys]] and [[TalkingAnimal talking animals]], however, this ends up being treated realistically, as the motor still winds down over time - but it undeniably lasts ''much'' longer than it used to.
* One of the plot hinges of ''Literature/AngelsAndDemons'' is that the production of antimatter has not only been vastly improved in efficiency, so that large amounts can be made (and stored), but it can now be made at a cost of less energy than will be yielded by annihilating it.
* The Ransom Apparatus of ''The Rise of Ransom City'', a machine that utilizes the Ransom Process[[note]] Professor Harry Ransom is, by his own admission, self-centered[[/note]] to "[strip] away the world and [reveal] the energy that lies beneath," generating both light and heat in infinite quantities (among other things, like altering local gravity and creating "ghosts" of people from alternate universes). It only works because it incorporates a [[FunctionalMagic rune]] of the [[MagicalNativeAmerican First Folk]] in its construction. Folk magic [[RealityWarpingIsNotAToy not being a toy]], the Process can be very dangerous when it [[GoingCritical melts down]]. While Ransom intended to use it to provide free light to everyone in the West, everyone else is more interested in its applications as a PhlebotinumBomb.
* The orrery in the Edgewood house in ''Literature/LittleBigOrTheFairiesParliament'' is apparently a perpetual motion machine powerful enough to supply all the energy needs of the house when no electricity is available. It may or may not technically qualify as one since it's driven by the actual motion of the planets via sympathetic magic, so it breaks the laws of nature but not actually the laws of thermodynamics.

* ''Series/BarneyMiller'': In "[[Recap/BarneyMillerS6E21 The Inventor]]", the inventor, Mr. Emery, claims that he has invented a battery that will never run out of energy, and that his bosses at Powerite Electronics suppressed his invention because they realized no one would buy batteries anymore. When Mr. Essex from Powerite shows up, he dismisses Mr. Emery as a nutcase--but he is determined to confiscate Mr. Emery's blueprints.
* Red Green attempted to make one in the "Handyman's Corner" segment of the GrandFinale of ''Series/TheRedGreenShow'', using only household items. He hooks up a lawnmower to an alternator that powers a ceiling fan located amongst some corn stalks. The fan chops off an ear of corn when the corn gets as high as an elephant's eye, sending the corn into [[KitchenSinkIncluded a sink]] with garbage disposal also powered by the alternator. The corn then falls into an oil drum where it decomposes into ethanol, where it gets siphoned back into the lawnmower. Meanwhile, the spare corn seeds gathered by the garbage disposal slide down a downspout to where the corn grows, so the corn keeps on coming. However, Red finds one problem in his "ultimate project". The lawnmower won't start. (And, of course, even if it had worked, it wouldn’t have been a true free-energy machine, because it depends on the input of external energy—sunlight—to grow the corn.)

* Snowpiecer in the [[Series/{{Snowpiercer}} television adaptation]] is played more realistically than the semi-mystical film version, but it is nevertheless an engine that not only perpetually generates energy, to the point of being able to get the entire train moving from a dead stop, but actually generates ''more'' energy when the train is in motion, providing power and heat to the other cars. All without any apparent source of fuel.

* The titular structure in ''VideoGame/TheEternalCylinder'', a massive, seemingly-endless rolling-pin-like device that crushes everything in its path. It's not clear exactly ''what'' powers it, and on occasion begins glowing red and starts rolling faster. While special towers, when activated, can halt it in its tracks, it can only be delayed temporarily, but never truly stopped.

* ''VideoGame/{{Portal}}'' fans have proposed several ideas for perpetual motion machines using the portal technology. Most of them revolve around the fact that if one portal is on the ceiling and the other is on the floor, any object thrown in would fall indefinitely.
* [[Franchise/{{Pokemon}} Poké Balls]] are able to change in size from a ping-pong ball to a baseball, convert Pokémon and items into energy and store them for indefinite periods of time, simulate a "Pokémon-friendly" environment that is "designed for comfort", communicate with a Trainer's Pokédex to automatically log data on captured species, and even ''teleport'' all without a visible power source. They never need to be charged and have been shown in [[Anime/{{Pokemon}} the anime]] to function perfectly after centuries of neglect. Yet [[ReedRichardsIsUseless this revolutionary level of technology is never shown to be applied to other aspects of life]], as humanity relies on conventional forms of energy despite quite literally having perpetual energy in the palm of their hands.
** ZigZagged in ''VideoGame/PokemonLegendsArceus'' as the Poké Balls in [[DistantPrequel that]] game lack the high-tech functions like [[NoConservationOfEnergy changing size]] and are essentially just hollow rocks.
* The Reapers in ''Franchise/MassEffect'' somehow work without fuel. In ''VideoGame/MassEffect3'' Codex it is outright stated how [[SufficientlyAdvancedAlien strange and impossible this should be]], as well as the fact that without need for resources and capable of replenishing their foot-soldiers from enemy ranks, the Reapers need absolutely no supply lines in war.
* ''VideoGame/TheIncredibleMachine'' has absolutely no concept of thermodynamics, making it easy to make perpetual motion machines in dozens of different forms. A power generator produces electricity from rotation, while an electric engine produces rotation from electricity. Place a generator, plug an engine into it, connect the wheels of the generator and the engine, add an initial source of energy (e.g. bellows and a windmill) - voilà! Perpetual motion.

* The ''VideoGame/TrailsSeries'' has a [[DownplayedTrope downplayed]] example in the form of Septium Quartz. As soon as a machine, called an Orbment, is outfitted with the necessary amount of Quartz, it will never run out of energy and will just keep going, and it's even outright stated to be leagues better and more efficient than conventional energy sources as fuel engines were in a testing phase untill Orbal Energy was discovered. However, machinery involving Quartz can still deteriorate, malfunction and break down, meaning that the "perpetual" part mostly means it has no need to be refueled or recharged.

* The [[NightmarishFactory Star Forge]] from ''VideoGame/KnightsOfTheOldRepublic'' is essentially this in both function and capability. By endlessly harvesting the practically infinite energy of a star, the Star Forge is able to create limitless amounts of droids, fighters and capital ships for those who control it. It, and everything made with the Star Forge's technology such as the Star Maps that lead to its location, are also capable of completely self-repairing themselves unless completely obliterated. Justified as [[spoiler: it's a mechanical [[EldritchStarship Eldritch Starship]] that is fueled by the Dark Side of the Force itself and heavily implied to be sentient.]]
* ''VideoGame/XenobladeChroniclesX'': The Ma-non's starship is stated to have a couple of perpetual motion machines aboard, generating power in each of its two wings. [[HigherTechSpecies They regard these as mundane technology]], one character compares how they view it to how humans view campfires. It is stated that the machine doesn't really output very much power ''at once'' though, so the Ma-non do require alternative fuels for more energy-intensive tasks.
* ''VideoGame/XenobladeChronicles'': The Conduit is described as a true perpetual motion machine, an infinite source of energy with the power to link dimensions and warp reality itself. The scientists working on it used it to create a massive SpaceElevator and an army of HumongousMecha, and this is mentioned almost as a ''side effect'' of its incredible power. One scientist claims that it is the only truly divine thing in the world. [[spoiler:The war over it destroyed the Earth when that scientist, Klaus, activated it without proper safety protocols. The Conduit was controlled by the Trinity Processor, the three parts of which became the three Aegises. In ''VideoGame/XenobladeChronicles1'', Alvis gives Shulk the power of the Conduit so that he can defeat Zanza (which is what Klaus has devolved into over countless eons), and in ''VideoGame/XenobladeChronicles2'' Mythra and Pyra activate their SuperMode of Pneuma to use the Conduit and stop Malos and the Artifices from destroying the world again]].

* There's a whole ''gallery'' of plans for these machines -- Donald Simanek's [[https://lockhaven.edu/~dsimanek/museum/unwork.htm Museum of Unworkable Devices]]. Some visitors to this site misinterpret Simanek's motivation as "seeking to eliminate the flaws of such machines so that they can be made workable"; of course, his actual motivation is to educate the public that those flaws are inherent and can ''never'' be eliminated.

* ''WesternAnimation/TheSimpsons'', "The PTA Disbands": Lisa is going crazy while the teachers are on strike and creates a perpetual motion machine. Homer calls a machine a joke, because it keeps going faster and faster, and tells Lisa that no physics law should be broken in his home.
-->'''Homer:''' ''Lisa, get in here! In this house, we obey the laws of thermodynamics!''
* In one episode of ''WesternAnimation/ChipNDaleRescueRangers'', [[GadgeteerGenius Gadget]] claims she once found a perpetual motion machine in the garbage can after a school science fair; of course, by then, [[SubvertedTrope it had stopped moving]].

* In one episode of ''WesternAnimation/{{Recess}}'', Gretchen invented one for a school project. It was immediately confiscated by the government. The [[CoolTeacher substitute teacher]] at the time gave her a passing grade.