"Dan Halacy is one of the great men of solar energy that were true heroes to young scientists and engineers in the solar energy era from the 1950s to the 1970s. With photos, drawings, illustrations and descriptions, this book provides the in-depth details of the history, theory, operation and future of fuel cells. This is one of the few books in existence that explicitly gives you step-by-step instructions for making a fuel cell." (Quoted from product description)