hand cranked electric generators - output?
352874
Okay, let's do the math:\n\nAssuming that 20 people could continuously produce 4W of electrical power for 8 hours without getting tired, here's how it would shake out:\n\n20 people x 4W  = 80W of power\n\n20 people x 5W  = 100W of power\n\nI could stop now at this point since the 8 hours now becomes irrelevant.  It would take all 20 people doing all they could just to keep one 100W light bulb glowing brightly.  The answer is clearly no.\n\nA ceiling fan requres roughly 100 watts...to keep it running.  It requires significantly more power momentarily upon start up, as does the refrigerator because they are electric motors.\n\nA refrigerator, depending on size, age and efficiency draws roughly 800 - 1200 Watts...when running.\n\nSo, 500 watts for ceiling fans, 800 watts for the fridge, 600 watts for the light bulbs...you're up to 2100 watts, or\n700 people cranking hand generators.\n\nI'd consider using compact fluorescents for your lighting.  ;-)
189503
how about looking at wind generators online and seeing how much power they generate.
252469
Generator generates electricity. It has a wire armeture mounted in an electic field. When the wire armeture is rotated, electric current is induced in the armeture du to change in magnetic flux.
952593
An electric generator is a device used to convert mechanical energy into electrical energy.\n\nThe generator is based on the principle of "electromagnetic induction" discovered in 1831 by Michael Faraday, a British scientist. Faraday discovered that if an electric conductor, like a copper wire, is moved through a magnetic field, electric current will flow (be induced) in the conductor. So the mechanical energy of the moving wire is converted into the electric energy of the current that flows in the wire.The mechanical energy needed to turn the generator comes from the brown hand crank at the front of the generator. In a hydroelectric power plant, the mechanical energy to turn the generator comes from the water turbine, which is turned by the force of falling water. The hand crank causes the red wire to spin inside a magnetic field (the blue lines). As Faraday learned, moving the wire through the magnetic field causes electric current to flow in the wire. The turning red wire is connected to a volt meter, which shows the amount of electric current that is produced. In a hydroelectric plant, the generator is connected to transmission lines that deliver the electricity to your home or business.\n\nThe controls allow you to control the speed and direction of the generator and turn portions on and off for greater clarity. You can also use the radio buttons to show a direct current, or DC generator (with commutator) or an alternating current, or AC generator (without commutator).
226076
I assume you mean diesel engine powered generators.\nDiesel generators come in lots of different sizes and generating capacities.  If you have seen three generators used for a concert, that is for one of two reasons: either they want to have redundancy (spares) - that is, to be able to quickly put another generator on line in case one fails, or the generators are small and they need three to provide enough electricity.\nIf there is a place where you live that rents generators, they might be able to help you with your project.
515778
British horsepower is also known as just horsepower.\nOne horsepower = 745.7 watts\nSee the howstuffworks link for an interesting look at horsepower.\n\nTo find the rated electrical input power required for a motor knowing the horsepower:\nkVA = (hp*.7457)/(eff*pf)\n\nwhere kVA = rated input power in kilo volt-amps\nhp = rated output horsepower\neff = motor efficiency (Pout/Pin)\npf = power factor of the motor\n\nIn general, a generator can take a load that is equivalent to the input power times the generator efficiency.  After all, a generator just converts energy from a mechanical form to electrical form with some losses in the process.  I admit that it isn't quite as simple as that, though, so I recommend further reading.\n\nTry Wikipedia, howstuffworks, etc for a start with general reading.  Those should lead to the more in-depth stuff.
247063
Running a small refrigerator using an electric generator is not very economical but can be done during a blackout.  It may be necessary to run the generator only periodically especially if you open and close the door oonly just before running the generator and check if the refrigerator is actually operating (listen for vibrations?) while you are running the generator.  If the refrigerator is small enough (dormitory type?) you may be able to use a DC/AC converter that plugs into an automobile cigarette lighter and a long extension cord.  Read the amps/watts/volts/hertz(60 cycle?) from the manufacturer's label and show that to the generator supplyer.  In a recent blackout, we used such a converter to run fans in a basement fireplace insert that heated the house burning firewood while tempertures dipped well below freezing outside (save the pipes!!!).  Good luck.
949031
Absolutely.  It's the way in which every electromechanical generator in the World works ☺\n\n\nDoug
865400
Get some power generators.
699391
For large or largish generators\nsteam turbines\ngas turbines\nwind turbines\nwater turbines\ndiesel engines
240172
You need to know more information.  How many Poles does the Generator have?  How many windings per pole?  Is it synchronous or a-synchronous?  What is the reduction ratio between the turbine and the generator?  Does the generator utilize an armature, brushes, or slip rings?  is the generator self exciting?  At what frequency will the output be?
786312
Since you're dealing with a variable energy source (wind), you're best bet is to build a DC generator...\n\nIs this a science progect?\n\nA DC Generator is the same machine as a DC motor...  So if you're building something for your home, then just use a DC motor and a simple belt an pulley to reduce the rotational resistance (or load) on the blades, so a slower wind can be used...\n\nFor a Science project...  \nBuid three loops of wire and seperate them 60° on the rotor of the wind mill.  Place a magnet on either side. north to south\nSet up "brushes" (chunks of graphite like pencil lead) on either side so that as the rotor spins with the wind, the same side is going to the same terminal + or - no matter which side of the coil it is.\n\nHave fun with it...
1169017
A voltmeter and an ammeter will provide the input power. You will need some form of dynamometer to measure output power.\n\nOutput power divided by input power yields efficiency.
366698
One word of caution! The generators must be in phase for you to connect them in series and that will be nearly impossible to find in a small, commercial generator.  Without very tight control over each generators sync with the other, you could end up with anything from approx. double one generators voltage to the voltage of one generator alone and most likely fluctuating in between.  This will reek havoc on many things you may want to run with it and destroy lots of others outright. It could be done with the right electronics, engine and generator modifications and know how, but it would also be very expensive and time consuming.  If you need a 480V genny, it's much easier to find a used industrial engine welder or scavange one for its transformer.
743232
I'd suggest a minimum 5kW generator.  I can't imagine the sewing machines being more than a few hundred watts operating power, and it is unlikely all five will start up at once for surge currents to add.  There should be plenty of headroom left over for the fans and lights.\n\nVisit my home generator page for other ideas.\nhttp://members.rennlist.org/warren/generator.html
99832
i believe it is around 9.5%.\n\nBecause Efficiency = O/p Power / Input power * 100.\n\nOutput is the given one \n= 4 * 104 J/min * 3 * 60 min = 74880 J \nInput is  = 75 * 1076 * 9.8 J ( mgh - mg * 0 = Potential energey) \nthefore, eff. is 9.5%\n\nplease reply at autoprash90@yahoo.co.in
46766
DC generator would have a rectifier built in to convert the AC to DC.