A quick stop at the fast-food restaurant to satisfy hunger with a burger and a portion of fries on a long car trip. Unnoticed, fast-food customers are becoming part of a circular economy. While they are ordering at the drive-thru, the used frying oil is being collected in the back. Off it goes to a different kind of refinery.
There, special technology turns the fryer grease into renewable diesel, which goes into the tanks of all kinds of vehicles - including those that collect the fryer grease. The quality of the fuel is now so good that it no longer needs to be added to conventional diesel, but can replace it 100 percent. Compared to fossil diesel, carbon dioxide emissions are 30 to 80 percent lower.
Renewable diesel is an option for land, sea and air
Producers say highest reduction of the carbon footprint can be achieved if the recycled fuel is made from 100 percent waste and residual materials. This is still very much a goal, not a reality. According to their own statements, leading companies report that this technology achieves a quota of a good 80 percent. To reach 100 percent and at the same time meet the quality requirements of end customers, the waste materials would have to be processed and purified even better before they could be used in the production of renewable diesel.
In the future, the fuel could also be used for global air travel and shipping. Leaving out the current crippling effects of the corona virus on the global economy, commercial aircraft are normally responsible for nearly three percent of carbon dioxide emissions. Shipping also emits large amounts of CO2, as 90 percent of globally traded goods and raw materials are transported by sea.
of globally traded goods and raw materials are transported by sea.
Urban waste and algae become fuel alternatives
Many renewable fuel producers are already working with the aviation and shipping industries to test the use of alternative fuels. If ships need a particularly low-sulfur fuel, aircraft engines have so far only been able to tolerate a maximum 50 percent blend of renewable fuel. To remain competitive and improve the global climate footprint, companies are already researching which other renewable raw materials they can use in their production. For aviation kerosene, for example, algae and urban waste are emerging as scalable fuel alternatives.
But critical to the widespread use of alternative fuels will also be how well refinery operators cooperate with major fuel suppliers and bunkering companies to ensure availability at airports, seaports, and bulk fueling stations.
Already, renewable fuels are saving millions of tons of CO2
Another source of hope is lignocellulose, the cell wall of lignified plants. This complex biopolymer is an attractive raw material for the production of fuels and chemicals, but it has been very difficult to extract. If a company were to succeed in developing an effective process for this, it would catapult the commercial use of biomass to the next level. This is because, up to now, mainly fruits such as barley and corn, i.e. potential foodstuffs, have been used as raw materials for bioethanol - which is the subject of controversial debate.
With the new bio-based fuel technologies, companies are making a significant contribution to an improved climate footprint. For example, one of the leading suppliers estimates that its renewable products will have reduced carbon dioxide emissions by 10 million metric tons by 2020. This is equivalent to the annual CO2 emissions of 3.7 million passenger cars.