Hydrogen economy small part (4% in 2006) is produced by electrolysis using electricity and water, consuming approximately 50 kilowatt-hours of electricity per kilogram of hydrogen produced. The Kværner-process or Kvaerner carbon black & hydrogen process (CB&H) is a method, developed in the 1980s by a Norwegian company of the same name, for the production of hydrogen from hydrocarbons (CH), such as methane, natural gas and biogas. Of the available energy of the feed, approximately 48% is contained in the hydrogen, 40% is contained in activated carbon and 10% in superheated steam. Hydrogen can be made via high pressure electrolysis, low pressure electrolysis
Hydrogen storage to convert carbon dioxide and hydrogen to methane, (see natural gas) using electrolysis and the Sabatier reaction. A third option is to combine the hydrogen via electrolysis with a source of carbon (either carbon dioxide or carbon monoxide from biogas, from industrial processes or via direct air-captured carbon dioxide) via biomethanation, where biomethanogens (archaea) consume carbon dioxide and hydrogen and produce methane within an anaerobic environment. This process is highly efficient, as the archaea are self-replicating and only require low-grade (60°C) heat to perform the reaction. Another process has also been achieved by SoCalGas to convert the carbon dioxide in