Central Versus Distributed Production
Central, semi-central, and distributed production facilities are expected to play a role in the evolution and long term use of hydrogen as an energy carrier. The different resources and processes used to produce hydrogen may be suitable to one or more of these scales of production.
Distributed Production
Hydrogen can be produced in small units where it is needed, such as at a vehicle refueling station, in a manner known as "distributed production." Distributed production may be the most viable approach for introducing hydrogen in the near term, in part because the initial demand for hydrogen will be low. Two distributed hydrogen production technologies that may offer potential for development and commercialization during the transition to a hydrogen economy are 1) reforming natural gas or liquid fuels, including renewable liquids, such as ethanol and bio-oil, and 2) small-scale water electrolysis.
Centralized Production
Large central hydrogen production facilities (750,000 kg/day) that take advantage of economies of scale will be needed in the long term to meet the expected large hydrogen demand. Compared to distributed production, centralized production will require more capital investment as well as a substantial hydrogen transport and delivery infrastructure.
Semi-Central Production
Intermediate size hydrogen production facilities (5,000 - 50,000 kg/day) located in close proximity (25-100 miles) to the point-of-use may play an important role in the transition to a hydrogen economy and in the long-term use of hydrogen as an energy carrier. These facilities can not only provide a level of economy of scale but also minimize hydrogen transport costs and infrastructure.
DOE and others are analyzing the options and trade-offs for hydrogen production and delivery during the transition to a hydrogen economy. Options other than distributed production may also play a role. For example, large hydrogen production facilities currently exist in or near petroleum refineries since they use hydrogen in petroleum processing. It might be possible to take a small fraction of this hydrogen and transport it to nearby refueling stations during the transition. Learn more about hydrogen delivery.