Introduction to Fuel Cells
A fuel cells is an electrochemical mechanism that produces power without combustion by joining hydrogen and oxygen to generate water and heat. The voltage created by a single cell is typically rather small (< 1 volt), so many cells are connected in series to create a useful voltage. Hydrogen fuel cells are feasible to modernize the way the globe visions, generates, and utilizes energy. So far, hydrogen has been used to power, mobile phones to NASA’s space programs etc.
At room temperature, hydrogen is:
· The easiest and most rich constituent
· Colourless
· Odourless
· Harmless
· Additional energy per weight than any other energy mediums.
· More proficient than current fuels used in transportation
· The only by products of Hydrogen Fuel Cells are water vapour, electricity, and heat translating to Zero Carbon Emissions
Fuel cells are really attractive from an ecological stand point.
Hydrogen Fuel and air contains oxygen react when they come into make contact with a porous membrane (electrolyte) which split them. This reaction end results in a transmission of electrons and ions across the electrolyte from the anode to the cathode. If an external load is fastened to this arrangement, a complete circuit is created and a voltage is generated from the stream of electrical current.
Fuel Cell vs. Battery
Essential operating principles of both are very similar, but there are numerous intrinsic differences.
| Hydrogen Fuel Cell | Galvanic Cell (Battery) |
|
|
Fuel Cell Vs. Internal Combustion Engine
| Similarities | Differences |
|
Fuel cell: |
· Output is electrical work.
· Fuel and oxidant respond electrochemically.
· Modest to nil pollution produced.
I.C. Engine:
· Output is mechanical work.
· Fuel and oxidant reacts by the process of combustion.
· Use of fossil fuels can generate considerable pollution.
Hydrogen Fuel Cell Efficiency
· 40% efficiency generated, converting methanol to hydrogen in reformer
· 80% of hydrogen energy content converted to electrical energy
· 80% efficiency for inverter/motor – Converts electrical to mechanical energy
· Overall efficiency of 24-32%
Auto Power Efficiency Comparison
Technology System
EfficiencyFuel Cell 24-32% Electric Battery 26% Gasoline Engine 20%
A hydrogen fuel cell is similar to a battery in that it generates electricity from an electrochemical reaction. Both batteries and hydrogen fuel cells exchange chemical energy into electrical energy and also, it generates heat as a by-product of this process. However, a battery holds a closed circuit which stores energy within it and once this is run down the battery must be disposing of, or recharged by using an external supply of electricity to force the electrochemical reaction in the reverse direction.
Likewise a fuel cell uses an external delivery of chemical energy and it can run for an indefinite period of supply with a resource of hydrogen cylinder and a source of oxygen (usually air). The resource of hydrogen is in general referred to as the fuel and this presents the fuel cell its name, even though at this instant, no combustion happened. Oxidation of the hydrogen as an alternative takes place electrochemically in a very proficient way. During oxidation, hydrogen atoms react with oxygen atoms to form water; in this method electrons are freed and flow through an external circuit as an electric current.
Fuel cells can differ from miniature devices producing only a few watts of electricity right up to large power plants producing megawatts. All fuel cells are based just about a central design using two electrodes divided by a solid or liquid electrolyte that carries electrically charged particles between them. A catalyst is regularly used to speed up the reactions at the electrodes. Fuel cells are normally classified according to the nature of the electrolyte they use. Each type requires particular materials and fuels and is suitable for different applications.