GS Caltex Executive Vice President Kim Chang-soo (left) and Korean Air Senior Vice President for Procurement Cho Seong-bae pose for a photo after signing a memorandum of understanding on testing sustainable aviation fuel in Seoul, Thursday. (GS Caltex)

South Korean oil refiner GS Caltex said Friday that it has teamed up with national flag carrier Korean Air to promote the demonstration of Sustainable Aviation Fuel to reduce carbon emissions in the atmosphere.

Through the partnership, GS Caltex will supply SAF -- an alternative to conventional fossil aviation fuel produced with biological and nonbiological resources -- to Korean Air on international flights departing from Incheon.

The two signed a memorandum of understanding at GS Tower in Gangnam-gu, Seoul, where key representatives including GS Caltex Executive Vice President Kim Chang-soo and Korean Air Senior Vice President for Procurement Cho Seong-bae were present.

Under the deal, both companies will jointly establish the necessary infrastructure and environmental conditions for the implementation of SAF. The test flights will take place over a six-month period starting in the second half of 2023.

The partnership is part of joining the government's initiative to boost the supply of biofuels, as announced in a governmental plan announced on June 8. Based on the test outcomes, the South Korean government plans to draw up guidelines for domestic SAF use and set quality standards before full-scale domestic production.

Led by the International Civil Aviation Organization, many efforts have been made to reach carbon neutrality by significantly reducing greenhouse gas emissions from aircraft by 2050. However, the conversion to electric or hydrogen fuel for aircraft lags behind other transportation sectors, as it faces volume and weight limitations.

SAF is expected to play a pivotal role in reducing greenhouse gas emissions in the aviation sector. Unlike nonrenewable fossil fuels, SAF is produced with animal or vegetable oils, algae and solid waste. It can reduce carbon emissions by up to 80 percent compared to conventional fossil fuels.

The European Union has mandated that airlines refueling in its territory use a minimum 2 percent SAF blend from 2025. Many countries, including the United States, are adopting various policies, such as tax incentives, to expand SAF production.

"This partnership with Korean Air will enable us to reaffirm and validate the roles and functions of each company in building the foundation for the introduction of sustainable aviation fuel in South Korea, in line with the global low-carbon trend,” GS Caltex Executive Vice President Kim Chang-soo said.

“We also plan to actively cooperate with the government and public institutions to promote the commercialization of SAF," Kim added.