Humans have burned wood, yak chips, fat from mammals, coal, oil, and the by-product from decomposing plant and animal matter (methane or “Natural Gas”) to scare away animals, provide light, cook food, heat homes, and eventually to power automobiles and industry. The by-products from combustion are usually a poisonous mixture containing different types of gases, particles, and sometimes unburned fuel.
One exception to poisonous combustion by-products is the reaction produced when Hydrogen and Oxygen are burned together. The by-product from these two gases is water vapor (H2O). Jewelers have been using torches powered by Hydrogen and Oxygen for many years. Hydrogen as a fuel is not without problem technologies and inefficiencies. But Hydrogen has distinct advantages as a source of power. Some of these are that the reaction does not produce poison during operation, storage, or during the process of electrolysis (where water is separated into Hydrogen and Oxygen gas).
This post is a quick introduction to Hydrogen fueled vehicles.