Are we breaking the laws of thermodynamics? I often wonder, in discussions of hydrogen as fuel, how one can provide energy to split water to get hydrogen and oxygen, then react them together as fuel, and expect ever to get a net gain in energy.

Tom Ostwald
University of California
Santa Barbara, Calif.

The media have lately become enthralled by hydrogen as the “clean, abundant energy source,” encouraged in this unfortunate deception by the auto industry. As you report, hydrogen is never an energy source, only a carrier and storage medium of energy from a source: electricity, heat, or light.

Bill Leighty
Juneau, Alaska

The article exaggerates the difficulty of water electrolysis as a hydrogen source. These H2 generators are easily powered by low-voltage sources characteristic of renewable-power technology. The thermodynamic efficiency and environmental advantages of hydrogen from solar- or wind-driven electrolysis are compelling. Personally, I think this could be a major energy contributor in only a few years, rather than the distant future suggested in the article.

Ron Blachman
Canton, Conn.