Japan’s challenge turning waste cooking oil into aviation fuel

After frying eggplant, Mrs. Maki Watanabe (Tokyo) pours the leftover cooking oil into a plastic bottle and waits to bring it to the nearby supermarket. That supermarket is one of 300 participants in the public-private “Fry to Fly” initiative, which aims to turn waste cooking oil into aviation fuel amid an energy squeeze caused by the Middle East conflict.

Japan aims to supply 10% of its total aviation fuel from sustainable sources (SAF), equivalent to 1.7 billion liters by 2030. SAF is one of the aviation sector’s emissions-reduction measures under the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA), which targets net-zero emissions by 2050.

Waste cooking oil is a relatively cheap feedstock for producing sustainable aviation fuel. However, industrial sources of this oil have already been largely collected. As a result, household contributors like Mrs. Watanabe have become important suppliers of input material for SAF production.

A resident brings leftover cooking oil to a collection point in Adachi ward, Tokyo, Japan, on April 18. Photo: Reuters

In reality, Tokyo collected only 160,000 liters of waste cooking oil in 2024. According to Reuters’ calculations, that amount is enough to produce enough SAF for a Boeing 787 Dreamliner to stay aloft for 17 hours.

To speed up collection from 7.8 million households in the capital, authorities have launched various public-private supply chain initiatives and raised public awareness. For example, last year they distributed 13,000 plastic funnels with QR codes instructing residents how to collect oil correctly.

Businesses have also begun participating by collecting oil from staff cafeterias. Fujifilm launched such a program this year. Major retailers Aeon, Ito-Yokado and 7-Eleven have added more waste oil containers on their premises.

However, even if every drop of waste cooking oil were used, the collected volume would still be small compared with demand. For someone who likes to cook like Mrs. Watanabe, the annual leftover oil she accumulates is about 40 liters. UCO Japan, an alliance of companies recycling used cooking oil, says that even at maximum collection rates, total recovered oil would be only about 550 million liters, enough to produce roughly one quarter of the SAF target.

A public official helps collect used cooking oil bottles for the “Fry to Fly” project in Adachi ward, Tokyo, Japan, on April 18. Photo: Reuters

For Eneos, Japan’s leading refining group, collection volume is a key factor when considering a joint venture with Mitsubishi Corp. to produce 400 million liters of SAF after fiscal 2028. Producing SAF requires a complex and costly process, from collection and feedstock treatment to distillation. If feedstock supplies are not secure, committing to SAF production poses substantial risks for companies.

A representative of engineering and industrial group JGC says investors need a clear demand outlook to justify scaling up production. Last year, together with energy group Cosmo Energy and biofuel maker REVO International, they started construction of Japan’s first commercial-scale SAF plant with a capacity of 30 million liters per year.

The effort to use used cooking oil highlights the carbon-reduction challenge facing aviation, one of the world’s largest greenhouse gas emitters. Failure to meet SAF production targets by 2030 would raise costs for refineries and airlines. That could mean refineries importing expensive crude SAF feedstocks, or airlines facing penalties for failing to meet sustainability requirements, with knock-on effects for flight operations.

ANA and Japan Airlines, the country’s two largest carriers, say they are “facing much harsher realities than expected” in the SAF field.

Motoomi Suzuki, a senior economist at the Norinchukin Research Institute, believes that until biojet fuel from ethanol is commercially available, SAF from waste cooking oil is the only viable near-term solution.

Bao Bao (via Reuters)