Fuel Cells - A Brief Introduction

Fuel cells are electrochemical devices that convert hydrogen and oxygen into electricity, heat, and water. The oxygen is generally pulled from the air, while the hydrogen is pulled from fuels such as natural gas, propane, liquid fuels, biofuels, or hydrogen.

Fuel cells, while similar to batteries or combustion engines that supply electric power, offer unique advantages. Whereas conventional batteries need to be recharged or replaced when their energy supply is depleted, fuel cells provide continuous power and life spans that can extend into years. Compared to internal combustion engines and gas turbines, fuel cells are quieter, less polluting, and can be 2-3 times as efficient. Because fuel cells meet all clean air and noise standards, the environmental community considers them a source of “green” energy.

Types and Applications

For many decades fuel cells and fuel cell systems have been the subject of a great deal of research and development. At this time, however, no single type of fuel cell has emerged as the answer to the world’s electrical power generation needs. Different types of fuel cells are generally distinguished by materials called electrolytes, each with different performance characteristics, which are needed for the electrochemical reactions that take place within the fuel cells.

Since all fuel cells are scalable, system sizes are determined by markets. There are two types of systems, sub-kilowatt systems, using shorter life, lower temperature fuel cell varieties that are suitable for battery replacement markets and kilowatt class systems, typically using longer life, higher temperature fuel cell varieties, that are suitable for mobile and stationary applications. Each is targeted at different applications, each with unique developmental challenges.

The TMI market entry system is positioned to provide low kilowatt range solutions in mobile, rural, and remote markets, where power availability and service support infrastructure may be weak or non-existent. In these markets, the small size and ease of use of TMI’s system provide a high value for end users.

More Information

The U.S. Department of Energy Web site offers more technical information about fuel cells and fuel cell systems, including information on:

• The basics of fuel cells, including a link to an animation depicting how fuel cells work.
• The different types of fuel cells that are currently being developed.
• The technical challenges that face those developing fuel cells.