Promising sustainable aviation fuel developed from Okinawan inedible subtropical plants: 100% biomass derived and compliant with international standards

On January 29, the New Energy and Industrial Technology Development Organization (NEDO) announced that J-Oil Mills, Inc. (Chuo City, Tokyo Prefecture) succeeded in producing 100% biomass-derived sustainable aviation fuel (neat SAF). J-Oil produced this fuel by pressing and refining oils and fats from seeds of Calophyllum inophyllum and Pongamia pinnata, which are wild subtropical plants found in Okinawa Prefecture and other areas and are not suitable for food use, under the "Demonstration Research for the Establishment and Expansion of a SAF Supply Chain Model Using Plant Oils and Fats without Competing with Food" project. The neat SAF produced meets the international quality standard "ASTM D7566 Annex A2."

SAF is a sustainable jet fuel made from waste materials, and its use helps reduce more greenhouse gas emissions than the use of fossil fuels. There is a growing demand for a stable supply of SAF as a concrete measure to reduce CO₂ emissions in the aviation industry. Japan has set a goal of replacing 10% (or 1.72 million kiloliters equivalent) of its jet fuel consumption with SAF by 2030. Currently, SAF made from waste cooking oil is expected to be the fastest to achieve successful large-scale production. However, NEDO estimates that the maximum amount of Japanese waste cooking oil available for fuel purposes is only 130,000 tons (about 140,000 kiloliters) per year, indicating the need to develop new oil and fat sources by 2030.

In this project, J-Oil used C. inophyllum and P. pinnata seeds that fell from roadside trees along Okinawa Prefecture-managed roads and developed an oil pressing and refining process suitable for them. Additionally, J-Oil commissioned Environment Energy (Fukuyama City, Hiroshima Prefecture) to perform hydrogenation, isomerization and distillation processes, and succeeded in producing neat SAF (100% pure jet fuel produced from biomass and other raw materials). The produced neat SAF was confirmed to meet the international quality standard "ASTM D7566 Annex A2" set by ASTM International, a private, non-profit organization in the United States that develops and certifies international standards.

In this NEDO project (August 2023 to March 2025), J-Oil focused on C. inophyllum and P. pinnata, which grow wild in Okinawa Prefecture. Leveraging the knowledge and techniques of oil extraction and refining developed through edible vegetable oil production, J-Oil has been working on a demonstration project to use these inedible plants as raw materials for SAF. Calophyllum inophyllum and P. pinnata are subtropical plants distributed across Southeast Asia and Okinawa Prefecture in Japan. In Okinawa, they are mainly used as roadside trees and windbreaks. Ovules of C. inophyllum and P. pinnata have high oil contents of 40%-50% and 30%-40%, respectively. These plants can be cultivated even on land unsuitable for farming, such as arid or high-salinity environments. In particular, these plants are expected to serve as new SAF feedstocks that do not compete with food production, as they have minimal competition with agricultural land and are generally not suitable for consumption.

Going forward, NEDO and J-Oil will collaborate with oil refiners and other companies with SAF conversion technology to achieve the goal of obtaining both fuel quality certification and environmental certification by registering as a CORSIA-eligible fuel under the International Civil Aviation Organization (ICAO). The two organizations will conduct cultivation demonstration tests to expand the supply of C. inophyllum and P. pinnata as feedstocks.