Syntetisk drivstoff

A plant will use 20 megawatts to produce 8000 tons of transportation fuel per year, This method will avoid producing 28,600 tons of CO2 annually from fossil fuels. 20 MW 24/365 is equivelant to 175 GWh/year. That could power electric cars for 1000 million kilometers or produce enough diesel to power fossile fuel cars 167 million kilometers. Rather trucks and airplanes, presumably, since they can’t be electrified, but it will not come cheap.

A company called Sunfire completed a test run of a high-temperature electrolysis reactor in September 2019, known as a solid-oxide fuel cell, that promises even higher efficiency than PEM electrolyzers. The reactor is at the heart of a four-stage test plant that generates fuel from water, CO2, and electricity. The first stage of the boxcar-size plant separates CO2 from air and then feeds the CO2 to Sunfire’s fuel cell.

It works a bit differently from its PEM counterparts: It uses electricity to split both water and CO2 at the cathode, generating a mix of CO, H2, and negatively charged oxygen atoms, or oxide ions. Those ions travel through an oxygen-permeable solid membrane to the anode, where they give up electrons and combine to produce O2. The mix of CO and H2, known as synthesis gas, then moves to a third reactor, which assembles them into more complex hydrocarbons. At the fourth stage, those hydrocarbons are combined with more H2 and refashioned into the mix of hydrocarbons in gasoline, diesel, and jet fuel. Because the plant works at high temperatures, the water- and CO2-splitting reactions convert electrical energy to chemical bonds at nearly 80% efficiency, the company says.

Sunfire’s test plant now makes about 10 liters of fuel per day. Norsk e-Fuel will build its first renewable fuel plant in Mosjøen, Norway – proving that e-Fuels can be produced economically. To reduce its CO2 footprint, aviation relies on renewable synthetic fuels (e-Fuels). The Norsk e-Fuel industrial consortium – of which Sunfire is the largest shareholder – plans to commission the most innovative and efficient industrial e-Fuels production plant in 2024. In the first expansion stage, it will produce 12.5 million liters per year. As of 2026, the plant’s production volume is expected to increase to 25 million liters of e-Fuel. At full capacity, the fuels produced reduce CO2 emissions from Norway’s five main domestic flight routes by 50 %.

https://www.science.org/content/article/can-world-make-chemicals-it-needs-without-oil