adminPROTON ENGINE
The proton engine is basically a proton exchange membrane (PEM) fuel cell engine. A proton exchange membrane (PEM) fuel cell uses hydrogen as the fuel and oxygen as the oxidant to produce electricity.
There are various types of proton engines or proton exchange fuel cells and they are; polymer electrolyte membrane (PEM) fuel cell, solid oxide fuel cell (SOFC), alkaline fuel cells (AFC), and phosphoric acid fuel cell (PAFC).
The proton engine or the proton exchange membrane fuel cell consist of the following components; anode, cathode, proton exchange membrane and an electrolyte.
The anode is the negative electrode where hydrogen is fed and oxidized to produce protons and electrons.
The cathode is the positive electrode where oxygen is fed and reduced to produce water.
The proton exchange membrane (PEM) is a thin porous membrane that separates the anode and cathode. It allows protons to pass through while keeping electrons out.
The electrolyte is the substance that facilitates the flow of ions between the anode and cathode.
Examples of materials used for the anode are; platinum (Pt), platinum-Ruthenium (Pt-Ru) alloys. Carbon –supported Platinum (C-Pt) etc.
Examples of materials used for the cathode are; platinum (Pt), platinum- cobalt (Pt-Co) alloy, carbon-supported Platinum (C-Pt) alloy etc.
Examples of materials used for the proton exchange membrane are; Nafion, Dow membranes, polymer electrolyte membranes (PEM) etc.
Examples of the materials used for the electrolyte are; phosphoric acid (H3Po4), sulfuric acid (H2So4), polymer electrolyte etc.
The principle of operation of proton engines is simply based on the reactions at the anode and the cathode. At the anode the hydrogen fuel is oxidized to produce protons and electrons. The protons migrate to the cathode through the permeable exchange membrane where it is reduced in a reaction with oxygen to produce water. The electron released during the process flow in an external circuit in the reverse direction producing electric current.
The advantages of proton engines are; they have practically no emission of any kind except water and heat. They have a higher efficiency compared with fossil fuel engines. They have a low operating temperature and are available as fuel in many forms such as hydrogen, methanol, ethanol etc.
The disadvantages of proton engines are; proton engines are more expensive compared to fossil fuel engines. They have limited infrastructure in place compared to fossil ones. They ate less durable and safe in their operation requiring regular maintenance and cumbersome handling and storage regulation.
Proton engines have a wide range of applications and this includes; proton engines find use in transportation, stationary power generation and for portable power sources such as batteries for phones and other devices.
The future of the proton engine depends on the trends and the development in the following technologies; improved materials, increased efficiency due to improved designs, reduction in the cost of proton engines as a result of mass adoption will drastically reduce the unit cost of proton engines thereby making competitive with fossil fuel engines.
SOURCES:
- Proton exchange membrane fuell cells by Frand Barbir.
- PEM fuel cells : Theory and practice by Andrzej Wieckowski.
- Fuel cell system by R. Keith Grassie.
- Fuel cells: From fundamentals to applications by Supramaniam Srinivan.
- Proton exchange membrane fuil cell modeling by J. Andre Benitez.
