Most liquid fuels used in transportation today are derived from petroleum and burned in internal combustion engines. These energy-dense fuels are currently economical, but they remain partially reliant on imported petroleum and are highly carbon intensive. Alternatives to internal combustion engines, like fuel cells, which convert chemical energy to electricity, have shown promise in vehicle powertrains, but are hindered by inefficiencies in fuel transport and storage. Projects in the Renewable Energy to Fuels Through Utilization of Energy-Dense Liquids (REFUEL) program seek to develop scalable technologies for converting electrical energy from renewable sources into energy-dense carbon-neutral liquid fuels (CNLFs) and back into electricity or hydrogen on demand. REFUEL projects will accelerate the shift to domestically produced transportation fuels, improving American economic and energy security and reducing energy emissions.