Infinite Energy With Fuel Cells?

In summary, putting a fuel cell and electrolysis in a circle produces infinite energy. However, the work done in electrolysing water is inefficient, and the cycle will eventually stop due to heat loss.
  • #1
NanakiXIII
392
0
I've got a problem. I tried to see what would happen when putting a fuel cell and electrolysis in a circle. I end up with infinite energy, so I must be doing something wrong.

Electrolysis

4 H2O -> 4 H+ + 4 OH-
4 H+ + 4 e- -> 4 H -> 2 H2 || The H2 is lead to the fuel cell anode
4 OH- -> O2 + 2 H2O + 4 e- || The O2 is lead to the fuel cell cathode, the electrons continue down the circuit to the fuel cell cathode

The electrons complete the circuit

Fuel Cell

2 H2 -> 4 H+ + 4 e- || The electrons are lead to the external circuit - electrolysis
4 H+ + 4 e- + O2 -> 2 H2O + heat || The circle is complete, the water can be lead to be electrolysed again


Now that all works out, you have an infinite circle with no particular use. Or do you? Where the protons, electrons and oxygen reunite into water, heat is produced. Thus you have infinite heat. Not possible, I'd think. What am I missing?
 
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  • #2
What about the work done in electrolysing water in the first place ?

You need to apply some potential difference V, and drive some current I. You are doing work at a rate of VI per second.
 
  • #3
the efficency of electrolysizing water into hydrogen and oxygen gas is roughly 50% I think, also, the efficency of a fuel cell taking that gas and recombining it into water is only about 50% aswell.
so if you start out giving it a certain amount of energy to start it off, after each cycle, there is only 1/4 of the previous total left (50% of 50%). it won't take long for the amount of energy remaining to be less than what is needed to break the water apart, so the cycle will stop. the problem is all the heat loss, both in electrolysis and in the fuel cell, energy, in the form of heat, is lost and unless you keep replenishing it, everything will come to a stop.
 
  • #4
I see, thanks.
 

Related to Infinite Energy With Fuel Cells?

1. What are fuel cells and how do they work?

Fuel cells are electrochemical devices that convert chemical energy into electrical energy. They work by combining a fuel (such as hydrogen) and an oxidant (such as oxygen) to produce electricity, heat, and water. The reaction occurs at the interface between the two electrodes, with the help of an electrolyte that allows ions to move between the electrodes.

2. Can fuel cells provide infinite energy?

Fuel cells can theoretically provide infinite energy as long as they have a constant supply of fuel and oxidant. However, in practical applications, the amount of energy produced is limited by the amount of fuel and oxidant available, as well as the efficiency of the fuel cell itself.

3. What are the advantages of using fuel cells for energy production?

Fuel cells have several advantages over traditional energy sources. They are highly efficient, with some fuel cells having efficiency rates of up to 60%. They also produce very little pollution, as the only byproduct is water. Additionally, fuel cells can be used in a variety of applications, from powering cars to providing electricity for homes and businesses.

4. Are there any limitations or challenges with using fuel cells?

One limitation of fuel cells is the high cost of production and installation. They also require a constant supply of fuel and oxidant, which can be difficult to obtain in some areas. Additionally, the technology is still relatively new and there are ongoing challenges with improving durability and reducing the size and weight of fuel cells.

5. What are some current developments in the field of fuel cell technology?

There is ongoing research and development in the field of fuel cells, with a focus on improving efficiency, durability, and cost-effectiveness. Some recent developments include the use of new materials, such as graphene and nanomaterials, to improve performance and reduce costs. There is also a push towards using renewable sources of fuel, such as biomass and solar energy, to power fuel cells.

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