Hydrogen seems like an ideal fuel, but a feasibility analysis reveals the factors that will determine its success.

Hydrogen has the highest energy density by weight of any fuel. So it only makes sense that compressed hydrogen gas is being considered as a carbon-free replacement for diesel in heavy-duty trucks. A hydrogen-fueled truck fleet would substantially reduce greenhouse gas emissions and other pollutants from the freight industry.

Before that can happen, engineers need to work out the optimum technology to make hydrogen economical as well as clean.