Permanent Magnet Generators

Batteries???

What's powering the generator??

I think you're trying to save AC energy instead of DC if I'm correct ?

Well, you get a million pound wheel and some really good bearings -- I recommend air bearings -- and then you spin up the big flywheel to as high a speed as you can (making sure that you haven't used a material which has a low tensile strength so that it won't fly apart from the centrifugal force), and then you just merely walk up to the fly wheel, take a little of its energy, use it for whatever you want, have a beer, and tell your neighborhood buddies, "I'll bet you wish you had one of these, huh?"

Oh yes, I meant to also say that some of the original power company generators used permanent magnet fields to generate power in hydroelectric plants, so essentially, if you use electricity from the power company to power your permanent magnet generator, you had better be able to exceed 100% efficiency to do it. If you're thinking about using a windmill, water wheel, wave, tidal power, or hydrocarbon fuel, you should also do an economic analysis to see how long it would take to save enough money to overcome the cost of producing your own electric power.

Ever heard of power transformation?

Obviously you are getting a bit of ribbing from this crowd because most of them are engineers that are fixated on the existing laws of physics and will not open their minds to the possibility that there are undefined variables they are not considering.

That being said, I think what you are asking is: "If a person were to build a permanent magnet motor to drive a generator, how would the A/C power be stored?" I am correct?

If so, the permanent magnet motor issue has been addressed elsewhere in this forum (do a search) and look on Google for plans, but it seems like a tough one and you will certainly not get much support from the scientific community on that issue.

On the A/C power storage, I think you are stuck with a battery and inverter situation. I use this set-up on sail boats all the time and it works, but it is not very efficient.

Stephan

P.S. Shame on you guys for not taking each and every question seriously!

I don't like the idea of people who actually solve real problems in this world being referred to as closed minded. Sure there was some mild ribbing, but that came mostly from the ambiguity of the question. Existing scientific law is very real and exists for a good reason. The progression of science and engineering has been going on for centuries and is the result of thousands of extremely intelligent folks picking apart other peoples ideas. The surviving ideas are seen as the truth, as a close as we can get to it. If you want to play in this game, then you had better suck it up and be able to take many shots, especially when you're on unsound ground.

You are 100% correct - my bad. Stephan

Well I assume the people who offered nothing practical were very young engineers or did'nt ask their munndad. I'm not an electrical engineer but more a reasonably successful "visionary" engineer. While using permanent magnets I noticed quite a strong force wanting to act on another magnet to make it move. Nothing new. Combining many of these I thought why not combine them around a rotor and also on the rotor and make the rotor rotate and create an emf in wires appropriately placed. Thereby creating electricity. Apparently with no external energy required. Assuming a low amount of emf induced we would need it to run continously. I assumed this would have been done but don't understand why it would'nt work to reduce power usage. In fact small devices could use the power straight away?? I assume it's due to power losses.

If I understand correctly, it sounds like you want to use the magnetic force arranged in a circle to turn a rotor. The problem you have is that when the magnets are placed in a circle you get a net force of zero because the forces counter one another. Keep thinking on the idea however, or give further clarification. I have seen designs for a "gravity motor" on the web. I don't know if works or not(probably not due to conservation of energy), but if it does, why couldn't the same idea be used with a magnetic field instead of a gravitational field. Regardless, the question of conservation of energy always comes up when considering something such as this. In a rotating system where is the gravitational potential energy stored? Insofar as storing the energy, there are alternatives to batteries and flywheels. The fuel cell guys store energy by electrolyzing water into hydrogen and oxygen. Keep in mind that each conversion to a different form of energy is less than 100% efficient so everytime you transform this energy you lose some. Any idea to ponder is, how can you use the energy directly instead of storing it?

The only really correct idea in his original posting is the desire to run the generator 24/7 and store the power for later use. A constantly turning engine which maintains a single speed is usually more efficient than one that stops and starts and has to accelerate often. That is why the hybrid vehicles are more efficient, using smaller more efficient gasoline engines running at a constant RPM and generating electricity which is used by an electric motor to provide variable drive torque. The storage medium for these is primarily deep cycle batteries, which allow the vehicle to travel short distances without running the engine, so as to reduce pollution in smoggy urban environments.

I won't even address the ridiculousness of the "perpetual motion machine" he is proposing.

"Open minds", indeed. Remember the quote from Ghostbusters:

Dr. Peter Venkman: Ray, pretend for a moment that I don't know anything about metallurgy, engineering, or physics, and just tell me what the hell is going on.
Dr Ray Stantz: You never studied.

dac:

Oh, please (giggle) tell me (snort), where DID you get your degree in Visionary Engineering (VE)? Was it from Imaginary University (IU)?

Yes, I know that is "offering nothing practical". However, the foolishness of your primary hypothesis begs ridicule. My high school physics teacher taught us all about "perpetual motion machines" and why they cannot work. You never studied, did you?

I am an experienced engineer with a hard-earned degree from a mid-western Engineering School with a well-known and well-deserved reputation.

There are lots of people that (wrongly) appropriate the title "engineer" for themselves. Some may call themselves Sanitary Engineers but they are still Garbagemen or Sewer Cleaners in my book! There are "Engineers" in industry who do not have degrees and function quite well up to a certain level, but they have usually bootstrapped themselves up to their position through self-study and experience. Even these experienced "Engineers" have limited capacity to explore new areas beyond their own experience or to "think outside the box", usually because they do not know their own limitations or that of the physical world they must deal with.

Visionaries must have a basis in reality or they become merely dreamers and fantasizers.

OK I see I'm wasting my time with you, end of discussion.

dac writes:
If I built a permanent magnet generator ran it 24-7 (continously) how would I store the energy for later use. (AC needed?). Why don't electric cars use them to recharge??

My (serious) reply:

Permanent Magnet Generator - Also known as an Alternator, supplies DC power from mechanical input, pulley, belt, wheel, gear, shaft, etc. which is powered by something else, hand crank, gasoline engine, steam turbine, water wheel, windmill, etc. TANSTAAFL

DC electrical power can be stored in many ways, some more efficient than others, and some more practical or less costly than others. Conventional deep cycle or medium cycle lead-acid batteries offer the biggest bang-for-the-buck, with the newer Absorbed Glass Mat (AGM) variety being the lightest, most efficient, and most reliable, although at a slightly higher cost. Other DC storage technologies would be less practical, including Kinetic Energy devices such as flywheels, Potential Energy devices such as wound springs, pumped water, pressurized air, lifted weights, etc. Pressurized air is well-known and has many uses, with many compressed air devices (espcially hand tools and industrial motors available) but would require extremely large tanks for deep-cycle usage.

To convert to AC power from batteries later would require a device commonly known as a power inverter, but you might be better off using DC-powered equipment because inverters are notoriously inefficient, although there have been some improvements made in newer designs.

Why don't electric cars use them to recharge? If by "them" you mean the Permanent Magnet Generators or Alternators, well in a sense they do. Hybrid vehicles use small gasoline engines to charge their batteries (see my other post).

If you mean some type of "free energy" device your answer is self-evident. In the words of a real engineer (BS-US Naval Academy) and true visionary, and one of my idols, Robert A. Heinlein:

"There Ain't No Such Thing As A Free Lunch!"

TANSTAAFL

I think dac has the idea that a static magnetic field can be stationary relative to static windings within which will flow an electrical current.

I just couldn't force myself to read too much, so I may have missed where someone told him that magnets and wires placed in close proximity to one another do not produce current. I still like my flywheel idea, though, in case he ever gets his visionary idea to work.

By the way, I'm not very young, but I am a visionary electrical engineer with 30+ years and several inventions under my belt, and if you can't stand the heat, get out of the kitchen.

Oops! I didn't notice I replied to your post, so the last sentence, " . . . if you can't stand the heat, get out of the kitchen," wasn't for you, it was for dac.

That's OK. I have taken plenty of heat in my time (over 25 years post-BS) rightly or wrongly delivered. I am reminded of what my Chinese Thermo professor said (in his broken English)after discussing the thermal cycle of jet engines, which included a "hot-side" (where combustion took place) and a "cold-side" (at the exhast):

"Less not keed oursells! Iffa you stan behine jet engine you gone get burn!"

In other words, "cold-side" is still pretty darn hot!

Moral:

If you can't stand the hot exhaust, get off of the tarmac!

Of course, I learned that lesson fairly early on. As Med-Evac Technician in the Air Force I worked or stood-by on many a flightline. You want to have plenty of distance between you and a jet making a turn on the taxiway prior to heading out to the runway for take-off. Its not a good idea to walk behind a parked aircraft during an engine test or start-up either!

Wow! That reminded me of one of the dumbest things I ever did . . . As an electrical engineering student, I took Thermodynamics in a six-week summer session. Not only did I have a hard time working the problems, I also had a hard time with the foreign language they used! It may as well have been Chinese.

Bill,

One of the dumbest things I ever did was the first week of Thermodynamics II. No instructor was listed for the course and everyone was in the class waiting for the instructor to show up, wondering who it would be.

When he did show up, 10 minutes late, two Seniors got up and walked out, directly to the Registrar's office to drop the course. By the end of the first week, only half the class was still enrolled in the course.

What was the dumb thing I did? NOT dropping the course the first week! I got a "D" and had to repeat the course. The next time, with a different instructor, I got a "B"!

Another dumb thing I did was to take a dynamics course taught by a professor I had known for a number of years, who I also knew didn't like electrical engineering students, and did well in the course for the first 8 - 10 weeks. As he was handing back quizes one day, he said, "I thought you were a mechanical engineering student; not an electrical engineering student." I got a "D" on that and subsequent tests. I dropped the course and got a "withdrew passing," on my transcript, because I knew it was a lost cause.

I eventually got a "C" in the course from a civil engineering professor, who I had also known for a number of years, but who was not prejudiced, although he liked to put me on the spot all the time by saying, "Let's ask the old man (I was in my mid-thirties at the time) if he know's how to draw the free-body diagram for this problem." The class got a chuckle out of his good-natured kidding, as did I.

The first prof I spoke of eventually got fired for discriminating against all but mechanical engineering students, even though he was a tenured professor. One of his dynamics classes consisted of 17 EE's and 5 ME's. All 17 EE's got "F's" and the ME's got "A's." The EE's protested and went to the department head, who went to the dean of the college, and who both confronted the professor whose stubbornness for refusal to rescind the grades cost him his job, which he thought was protected by his tenured status.

Other than that fatal flaw in his character, he was actually a pretty a nice guy. Weird . . .

Sounds like he got flunked by a EE professor when he took Electrical Circuits as a ME student! (chuckle)

By the way, do you kow the difference between ME's and CE's?

ME's build weapons, CE's build targets! (grin)

Yep -- I heard that one a long time ago.

By the way, I'm designing a "better mouse trap" in the form of a trebuchet. (I know -- a mouse trap is more like a catapult or a mangonel. I was using the "better mouse trap" analogy from historical uses of the phrase.) Mine will use a vertically dropping counterweight, similar to a "floating arm trebuchet," invented in 1998, but I've added a little twist that ought to improve the performance of such a machine.

All I need now is a CE to design a target I can destroy with golf balls.

You said you are 'designing a "better mouse trap" in the form of a trebuchet.'

Wow, what an image. A piece of cheese is sitting in the Trebuchet. Poor unsuspecting "Chuckie Cheese" climbs up inside to get the cheese when, ZING!......he flies through the air and slams into the wall, SPLAT! What a mess. Oh, well, back to the CAD screen!

Let's see, what practical uses can be made for a golf ball slinging trebuchet....hmmm....

Wait a minute.....(idea forming)....

I got it! How about a training aid for caddies learning to duck and cover?