Rendered animal fats from poultry, pigs and cattle have been used for many years in pet food and the oleochemical sector for soaps and cosmetics. But their use as transport fuels, currently mostly in cars and trucks, is causing alarm to climate scientists, particularly as aviation companies have recently struck deals with suppliers for “sustainable aviation fuels” (SAF) which often include animal fats.
A study, carried out by Cerulogy for clean transport campaign group ‘Transport and Environment‘, found that supplies of animal fat in biodiesel has grown fortyfold since 2006. Demand for animal fats in biofuels is also projected to triple by 2030 compared to 2021. This feedstock is expected to be the most used materials in SAFs after used cooking oil, with fuel suppliers heavily investing in the processing of animal fats for biodiesel and other fuels.
Europe already burns 46% of all animal fat feedstocks as biodiesel, according to the study, making transport the largest user of such fats. But its availability is finite and Transport and Environment calculates that to entirely fuel a transatlantic flight between Paris and New York, you would need 8,800 dead pigs each way. Carbon dioxide emissions of animal fats biofuels could be up to 1.7 times worse than conventional diesel.
There’s not a never ending supply of animals, or animal fat.
Matt Finch, Transport and Environment spokesman, told the media that there could not be enough animals slaughtered to meet airlines’ growing demand for animal fats: “There’s not a never ending supply of animals, or animal fat.
“So, if you put on a massive extra demand source from anywhere from aviation, the industries where fat is currently being used, will have to look for alternatives. And that alternative is palm oil. So aviation indirectly, will be responsible for increasing the amount of palm oil being pulled through the European systems.”
Both the UK and EU governments are keen to make aviation greener, putting in mandates that are requiring airlines to use more SAF in their tanks. For the EU, it will be 6%, while the UK is asking for 10%. The UK is likely to limit the use of better quality tallow in fuel – while in Europe the use of this type of material will be incentivised as the greenhouse gas reduction achieved with this fat is higher.