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How are magnets being used as an alternative energy?
Magnets are plenty useful in conventional energy conversion systems. They’re essential in the generators which convert chemical or nuclear energy to electrical forms via mechanical forms, and in the motors which convert that back to mechanical energy.
As for the ’alternative’ uses, in which the magnets are supposed to be sources of limitless energy themselves, they’re fakes, pure and simple. They violate fundamental physical laws, so it’s not surprising that they never actually work when tested by someone who isn’t selling stock in some bogus company.
(published on 10/13/06)
Follow-Up #1: alternative magnet energy
But I heard that magnets are a reliable alternative energy source from many knowlegable sources.
You might try asking those ’reliable sources’ to show you a single working model. And remember, it better not have hidden batteries or wires.
p.s. Did they tell you it’s a ’slam-dunk’?
(published on 03/03/07)
Follow-Up #2: magnetic energy?
I don't know how much sense this makes, but, with the aid of the earth's magnetic field, couldn't we make super magnets?
And, if so, wouldn't it be an alternative magnetic energy source?
Law of conservation has destroyed all of my other energy ideas.
Right now I'm working on a bike. =)
- Stephen Lupton (age 15)
I'm not sure what you mean by 'super magnets'. The Earth's field isn't of much use in making strong magnets of any type, since it's thousands of times weaker than field you can easily make with ordinary lab electromagnets.
Yeah, the conservation of energy (First Law of Thermodynamics) does put a crimp in a lot of schemes. So does the Second Law.
The idea of actually using the substantial work exerted on an exercise bike to charge some batteries sounds great.
(published on 02/02/09)
Follow-Up #3: zero-point energy
This is more than likely absurd, but I heard that the symmetry breaking that produced the universe should have had much more energy released in the process...The line of reasoning being that the energy density of free space is therefore quite large and that by cleverly creating an open system, it could be possible to extract zero point energy...These guys (Moray B. King) were looking at concepts like noise from diodes, all the way up to balls of plasma.
Is there anything to this at all? If you were to create some sort of self sustaining dynamo action, could it be checked for anomalous energy?
- Deon (age 23)
We do not know whether the vacuum is in its lowest possible energy state. It is possible that it isn't, which is one way of accounting for the dark energy driving accelerating expansion of the universe. Perhaps in some far distant future it will switch to an entirely different state via a phase transition, essentially wiping out whatever was there beforehand. That may have happened once already in an early inflationary era.
And no, the claims that fooling around with plasma balls or diodes will access this hypothetical energy source have absolutely nothing to support them. No experimental evidence, no actual theoretical arguments, nothing
(published on 10/21/09)
Follow-Up #4: energy from magnets?
I understand that magnets cannot be used as a limitless source of energy, but is it possible then for them to be used as long-lasting sources of energy. The like does not exist yet, but perhaps some system can be used to make use of this source of energy that lasts a long time?
- Thomas (age 15)
Melbourne, FL, U.S.A.
There's very little energy stored in that magnetization. A good permanent magnet has some field energy that could be lowered by losing its permanent magnetization. Very roughly, that energy is around 0.1J/cm3 times the magnet volume. So taking a big magnet (say 1000 cm3 volume) one might be able to extract about 100 J from it. You could light a nice bright high-efficiency LED bulb for about 10 seconds with that energy.
What magnets are good for is not as an energy source but as part of devices to convert mechanical energy to electrical and vice versa- generators and motors. Wind turbines, for example, use particularly strong special magnets in their generators. The energy comes from the wind.
(published on 11/11/13)
Follow-Up #5: What is magnetic field energy?
When you say energy stored in magnetization, do you mean the energy gained from the domains?
I don't understand what is meant by field energy, please do explain.
- Holvets (age 24)
There are a couple of ways of thinking of this. Classical fields (electric, magnetic, gravity) describe forces between objects. The potential energy changes as the objects get closer or farther, with the rate of change just being the force. In each case you can mathematically show that the potential energy can be written as an integral over space of the square of the field. Likewise the energy change that happens when two domains change the relative alignment of their magnetizations can be described as a dipole-dipole interaction between two magnets or equivalently as a change in that field energy. When the fields are propagating, as with electromagnetic waves, the same field energy description accurately gives the energy flow. So it makes sense to say that the field itself is where the energy is located.
Quantum mechanically, everything consists entirely of fields, including things we often picture as classical particles, so if energy is to mean anything there had better be a way of describing it as field energy.
(published on 12/03/13)
Follow-up on this answer.