What is the difference between Ballards Proton Exchange Membrane (PEM) fuel cell technology and others such as solid oxide and phosphoric acid?
PEM fuel cells use a solid polymer membrane (a thin plastic film) as an electrolyte as opposed to a liquid or high-temperature ceramic. PEM fuel cells are compact and produce a powerful electric current relative to their size. They operate at a lower temperature (less than 100 degrees Celsius or 212 degrees Fahrenheit) which allows for faster start-up and rapid response to changes in the demand for power (load following). PEM fuel cells are ideally suited to transportation and smaller stationary applications (under one megawatt) and have been demonstrated by Ballard in systems ranging in size from 100 watts to one megawatt.
