why can't self-powering generators be considered a source of alternative energy?

Question

like, say a windmill generates electricity, and you use 1% of that energy to power a box fan to put in front of the windmill. if electricity is generated with motion, it seems it would be a very simple matter to make a device that generates its own power, but generates a surplus of power, in which the leftover power is used by cities etc. why isn't this principle considered a practical solution?

Answer 1

Google "perpetual motion". Loss of enrgy during transfer is the reason you can't create the machine you mention. You have to add power to get the effect you're after. Unlees your windmill was able to caprture and convert every ounce of energy created by the blades of the box fan, you've already lost ground...

Just put the damned windmill in a windy area and put the box fain in your window.

Answer 2

You are up against a fundamental principle. Every, all, no exceptions, change of energy forms, consume energy, that is, you never get as much as you put in. If you put a fan to generate wind for a windmill, the energy output is less (much less) than you used to drive the fan. Energy converters always lose energy. This rule is the one that made all attempts to create an "Eternal Motion Machine" impossible. Even if you get zero power out, It is impossible to keep something moving forever.

Answer 3

because in order to make the windmill turn by blowing it with a fan the fan would need to be bigger and stronger than the windmill itself.

You cannot get power (in the form of electricity) out of any device unless you put that amount of power in - plus the windmill will have several other 'losses' - like the friction between the shaft and it's housing etc. - so in fact you always have to put quite a lot more power into a generator than you can get out.

so the box fan you want to put in front would need to blow with more power than it needs to turn the windmill - that in turn would also have losses so you would need to put even more electricity into your box fan - in fact considerably more than the windmill was generating.

If only your idea would work we would have had all the power we ever needed years ago - and all our vehicles would run on perpetual motion, all down to mechanical losses I'm afraid.

Answer 4

If you're just using 1% of the windmill's energy to power the box fan, it won't create very much wind. It's actually a waste of energy because instead of directly using the energy from the windmill, you're converting it to electricity to power the fan box which converts it to wind which turns the windmill slightly whcih converts it back to electricity. These processes aren't 100% efficient, so you're just wasting the energy you could have used directly.

Even the cogeneration units mentioned by ME which utilize normally wasted heat from power generation are only on the order of 80% efficient.

Answer 5

That is an old, old idea. It is yet another kind of perpetual motion machine. And it does not work. You need over 100% of the power of the windmill to make enough wind to turn the windmill. It is conservation of energy. There is no free energy. If there were, we would already be using it. Ideas like these have been proposed and build for centuries. They just do not work for very easy to understand reasons. At least easy to understand for anybody trained in pyhsics. But quacks and frauds continue to try and get money to develop such machines.

Answer 6

You would have to create a system that is at least 101% efficient. As far as I know, there is nothing that is 100% efficient. If you know a way, you'd be the first to invent perpetual motion. Otherwise, you are just wasting energy trying to power the box fan to run the windmill.

Answer 7

The oil, coal and car manufacturing industries have been fighting energy Independence for three decades. In the mid and late 70's after the Oil Embargo we set out to become energy indeedndent. We lowered the national speed limit to 55, we made the car manufacturers double their fleet's mileage, and we cleared years of red tape and law suits to create the Alaskan Pipeline. When Reagan came to office he basically killed the plan and increased oil imports by 50%. And yes, solar and nuclear is expensive and unpopular with many--and though we can become energy independent, the lobbyists and special interest groups will never allow it to happen.

Answer 8

There is no such thing as a self-powering generator. All generators convert one form of energy into another form that can be used for other purposes.

Answer 9

It is impossible to generate more power out of a device than you put into it. This is the basis for the study of thermodynamics.

Answer 10

its not as easy to produce energy as you probably think it is. Chemical plants and refineries use what you are talking about. Its called a co-gen unit. When plants make a certain product sometimes they produce steam which creates energy through turbines. That they sell to electric companies.