E-diesel

E-diesel is a synthetic diesel fuel created by Audi for use in automobiles. Currently, e-diesel is created by an Audi research facility in partnership with a company named Sunfire. The fuel is created from carbon dioxide, water, and electricity with a process powered by renewable energy sources to create a liquid energy carrier called blue crude (in contrast to regular crude oil) which is then refined to generate e-diesel. E-diesel is considered to be a carbon-neutral fuel as it does not extract new carbon and the energy sources to drive the process are from carbon-neutral sources. As of April 2015, an Audi A8 driven by Federal Minister of Education and Research in Germany is using the e-diesel fuel. Sunfire, a clean technology company, operates a pilot plant in Dresden, Germany. The current process involves high-temperature electrolysis powered by electricity generated from renewable energy sources to split water into hydrogen and oxygen. The next two chemical processes to create a liquid energy carrier called blue crude are done at a temperature of and a pressure of . In a conversion step, hydrogen and carbon dioxide are used to create syngas with water as byproduct. The syngas, which contains carbon monoxide and hydrogen, reacts to generate the blue crude. Sunfire power-to-liquids system: Base products are carbon dioxide (CO2) and water (H2O) 1st step: Electrolysis of Water (SOEC) −water is split into hydrogen and oxygen. 2nd step: Conversion Reactor (RWGSR) −hydrogen and carbon dioxide are inputs to the Conversion Reactor that outputs hydrogen, carbon monoxide, and water. 3rd step: F-T Reactor −hydrogen and carbon monoxide are inputs to the F-T Reactor that outputs paraffinic and olefinic hydrocarbons, ranging from methane to high molecular weight waxes. The final step is also known as Fischer–Tropsch process which was first developed in 1925 by German chemists Franz Fischer and Hans Tropsch. After the blue crude is produced, it can be refined to create e-diesel on site, saving the fuel and other infrastructure costs on crude transportation.