Sasol Ltd. has begun selling sustainable aviation fuel to a company that organizes luxury trips to Antarctica. This move taps into a new market that may help reduce its environmental footprint.

South African jet-fuel suppliers need to keep higher stock levels in the event of production outages, such as the one that occurred at Sasol Ltd.’s Natref refinery last week and prompted airlines to make backup plans, Chief Executive Officer Simon Baloyi said.

Sasol Ltd. said an unplanned stoppage at its Natref refinery has curtailed jet-fuel supplies to South Africa’s busiest airport, prompting airlines to make contingency plans to avoid disruptions.

Sasol Ltd., the world’s largest producer of fuel from coal, is reaping the benefits of a surge in fuel prices due to the Iran war, while helping shield its home market of South Africa from the resulting supply shock.