For carbon-free hydrogen to play a significant role in decarbonization, it will need to be produced in large quantities at low cost to compete with hydrocarbons. In a future power system heavily dependent on intermittent renewables, hydrogen will likely find economical use in power storage for grid balancing. However, for an actual ‘hydrogen economy’ to arise, hydrogen will have to expand into the so-called ‘hard to abate’ sectors where a large portion of carbon emissions occur. Hydrogen for direct heat in industry, and hydrogen-derived fuels (synthetic fuels such as ammonia and synthetic hydrocarbon fuels produced from hydrogen and CO2), would displace the liquid hydrocarbons now used in heavy industry (cement, chemicals, steel), heavy shipping, and aviation. The International Energy Agency sees this shift as necessary to eventually reach carbon-neutrality in the global energy system. In its Sustainable Development Scenario, emissions in the industrial and transport sectors remain stubbornly high […]