Energy Distribution in Wheel - Can Multiple Dynamos Increase Output Power?

AI Thread Summary
Using exercise bikes to generate electricity raises questions about the efficiency of multiple dynamos connected to a single wheel. The consensus is that the total power output cannot exceed the mechanical input from the user, adhering to the principle of conservation of energy. When connecting multiple dynamos, each would contribute less power than the total output, as the input energy remains constant. Discussions also highlight that if one generator is more efficient, it would be better to use that alone. Ultimately, the concept of generating more power than is inputted is dismissed as pseudoscience.
Young Learner
Messages
40
Reaction score
0
Recently I heard about using exercise bikes to generate electricity. It is more or less like a bi-cycle fixed in a training stand. They convert the rotation of the wheel into electrical energy.

The scenario is that they take some W watt of power from that model. In their case a disc like arrangement is used to transfer the rotation to a dynamo or a generator (I am not sure about, what is the difference between using a dynamo and DC generator).

My question is if I use a shaft kind on arrangement on either side of the same wheel and connect it to two different dynamos, will I get 2W watt of power or will the two dynamos separately contribute (W/2) watt of power and thus contributing the same W watt of power.

If I make an arrangement such that both the wheels get rotated when you peddle the bi-cycle (Assuming both the wheels are not in contact with the ground i.e both the wheels lie above the ground as a training stand is used). Having one shaft on either side of the two wheels, Therefore, getting output from 4 shafts and using four different generators, will I get 4W watt of power or will the power from each dynamo be (W/4) watt of power, thus contributing the same W watt of power.
 
Engineering news on Phys.org
Young Learner said:
Recently I heard about using exercise bikes to generate electricity. It is more or less like a bi-cycle fixed in a training stand. They convert the rotation of the wheel into electrical energy.

The scenario is that they take some W watt of power from that model. In their case a disc like arrangement is used to transfer the rotation to a dynamo or a generator (I am not sure about, what is the difference between using a dynamo and DC generator).

My question is if I use a shaft kind on arrangement on either side of the same wheel and connect it to two different dynamos, will I get 2W watt of power or will the two dynamos separately contribute (W/2) watt of power and thus contributing the same W watt of power.

If I make an arrangement such that both the wheels get rotated when you peddle the bi-cycle (Assuming both the wheels are not in contact with the ground i.e both the wheels lie above the ground as a training stand is used). Having one shaft on either side of the two wheels, Therefore, getting output from 4 shafts and using four different generators, will I get 4W watt of power or will the power from each dynamo be (W/4) watt of power, thus contributing the same W watt of power.

You only get out what the human puts in. At best (with 100% efficient generator), if the human puts in 100W of power by pedaling, then the generator can put out 100W of electrical energy. You cannot get out more power than is put in by the human.
 
  • Like
Likes 1 person
berkeman said:
You only get out what the human puts in. At best (with 100% efficient generator), if the human puts in 100W of power by pedaling, then the generator can put out 100W of electrical energy. You cannot get out more power than is put in by the human.

I still have a doubt. Assume a bus is moving at some speed. A small generator is connected on one side of a wheel. W watt of power is obtained. If another generator is connected on the other side of the same wheel would the output be the same W watt.

Assume that the mechanical input is x when only one generator is connected, the power produced is W watt. I doubt whether two 2x input of mechanical energy would be needed to produce 2W watt of electrical power. I believe when two generator is connected, the mechanical input required to produce 2W of power would require a mechanical input less than 2x.
 
If that were true, it would violate conservation of energy, which is a fundamental law of the universe.

Moreover, every engineer would already be powering their house from a stationary bike.
 
Young Learner said:
I still have a doubt. Assume a bus is moving at some speed. A small generator is connected on one side of a wheel. W watt of power is obtained. If another generator is connected on the other side of the same wheel would the output be the same W watt.

Assume that the mechanical input is x when only one generator is connected, the power produced is W watt. I doubt whether two 2x input of mechanical energy would be needed to produce 2W watt of electrical power. I believe when two generator is connected, the mechanical input required to produce 2W of power would require a mechanical input less than 2x.

I suppose if you believe that then you will also have trouble answering this question "If one man can dig a hole in 10 minutes, how long does it take 7 men to dig 7 holes?"

Basically, it is Power in = Power out, and energy in = Energy out.
If the second generator is more efficient in converting mechanical energy to electrical energy, then disconnect the first generator and use the second.
 
Young Learner said:
I still have a doubt. Assume a bus is moving at some speed. A small generator is connected on one side of a wheel. W watt of power is obtained. If another generator is connected on the other side of the same wheel would the output be the same W watt.

Assume that the mechanical input is x when only one generator is connected, the power produced is W watt. I doubt whether two 2x input of mechanical energy would be needed to produce 2W watt of electrical power. I believe when two generator is connected, the mechanical input required to produce 2W of power would require a mechanical input less than 2x.

Over-unity energy generation is a forbidden topic here on the PF. Your thread is closed. Please do not post like this again here.

PF Rules said:
Pseudoscience, such as (but not limited to):

Perpetual motion and "free energy" discussions
http://wiki.4hv.org/index.php/Free_Energy_Debunking
http://en.wikipedia.org/wiki/Perpetual_motion
http://www.skepdic.com/freeenergy.html
http://www.skepdic.com/perpetual.html
 
Posted June 2024 - 15 years after starting this class. I have learned a whole lot. To get to the short course on making your stock car, late model, hobby stock E-mod handle, look at the index below. Read all posts on Roll Center, Jacking effect and Why does car drive straight to the wall when I gas it? Also read You really have two race cars. This will cover 90% of problems you have. Simply put, the car pushes going in and is loose coming out. You do not have enuff downforce on the right...
I'm trying to decide what size and type of galvanized steel I need for 2 cantilever extensions. The cantilever is 5 ft. The space between the two cantilever arms is a 17 ft Gap the center 7 ft of the 17 ft Gap we'll need to Bear approximately 17,000 lb spread evenly from the front of the cantilever to the back of the cantilever over 5 ft. I will put support beams across these cantilever arms to support the load evenly
Thread 'Physics of Stretch: What pressure does a band apply on a cylinder?'
Scenario 1 (figure 1) A continuous loop of elastic material is stretched around two metal bars. The top bar is attached to a load cell that reads force. The lower bar can be moved downwards to stretch the elastic material. The lower bar is moved downwards until the two bars are 1190mm apart, stretching the elastic material. The bars are 5mm thick, so the total internal loop length is 1200mm (1190mm + 5mm + 5mm). At this level of stretch, the load cell reads 45N tensile force. Key numbers...
Back
Top