Hydrogen is already a major commodity in the U. economy and production could readily be expanded to serve new markets. More than 50 million metric tons are produced annually worldwide (11 million metric tons in the United States), principally from SMR (steam methane reforming) of natural gas. Much of this hydrogen is used in petroleum refineries, in the production of ammonia for fertilizers and other chemicals, and in food processing. Current hydrogen output is sufficient to provide fuel for 250 million fuel cell vehicles worldwide (55 million in the United States).
Given the emergence of large and accessible natural gas resources in the United States at historically low prices, hydrogen production using traditional central SMR technology could increase substantially to serve new fuel cell vehicle markets without straining the natural gas supply system and at the same time reduce petroleum imports. Large and small-scale hydrogen production technologies are already commercially available.
Central SMR is a mature technology and produces low cost hydrogen in the range of $1.50/kilogram at plant gate at current natural gas prices. The cost reduction experience curve indicates a steady but modest 0.5% annual cost decrease over the past 20 years.
Hydrogen gas and liquid produced centrally are typically delivered to customer sites by tube trailer or liquid tanker truck. The carriage cost varies with distance traveled but is nominally $1.25/kg. Hydrogen produced in large-scale SMR facilities that is delivered, compressed, and dispensed at a typical station is actually less expensive than gasoline on a miles traveled basis when used in fuel cell electric vehicles (FCEVs). It is likely that a substantial portion of the early hydrogen infrastructure will use this supply mode.
Alkaline and proton exchange membrane (PEM) electrolyzers are manufactured by several companies internationally and are currently capable of producing up to 1,000 kg/day with concepts for as much as 50,000 kg/day.