S-Oil Targets Next-Year Startup for Shaheen Project Amid Korea's Petrochemical Glut

S-Oil said on August 18 that the Shaheen project, its petrochemical complex under construction in Ulsan, remains on track to begin commercial operation next year — and that the refiner expects the plant to strengthen the global competitiveness of South Korea’s petrochemical industry at a moment when the sector is straining under oversupply. The announcement frames Shaheen not as an expansion for its own sake but as a production base built to compete on cost against newer capacity elsewhere in Asia and the Middle East.

A Startup Date That Doubles as a Message

The timing of the statement matters as much as its content. Korean petrochemical producers have spent the past several years squeezed between weak downstream demand and a wave of new capacity, and the industry’s excess supply has become a standing policy concern in Seoul. Against that backdrop, S-Oil’s confirmation that Shaheen will come online next year reads as a deliberate counterpoint: rather than idling or consolidating, the company is arguing that the answer to a glut is capacity that sits far enough down the cost curve to run profitably when older plants cannot.

That argument rests on integration. Shaheen ties petrochemical production directly into S-Oil’s refining complex in Ulsan, converting a larger share of each barrel into chemical feedstock rather than fuel. Globally, roughly 10 percent of petroleum consumption already goes to synthetic feedstock rather than energy use, and refiners with shrinking fuel demand have been pushing that ratio higher wherever their configuration allows.

Why the Chemistry Favors Integrated Plants

The economics of the project trace back to the basic arithmetic of cracking. Steam cracking of naphtha at furnace temperatures of 700–800°C, with residence times of less than a second and a half, typically yields a slate led by ethylene at about 27 percent, alongside roughly 15 percent propylene, 14 percent methane, an 11 percent C4 fraction, and about 18 percent cracked gasoline. Ethylene is the prize in that slate: close to half of global ethylene output is consumed making polyethylene, the workhorse plastic of packaging and consumer goods.

Because the product mix is largely fixed by the chemistry, the competition between producers comes down to feedstock cost and thermal efficiency — which is precisely where refinery-integrated projects like Shaheen claim their edge. A cracker that draws feedstock from an adjacent refinery, and returns its by-product streams to it, avoids much of the logistics and margin leakage that standalone plants carry.

The Stakes for Ulsan and the Wider Industry

For Ulsan, the country’s petrochemical heartland, a successful startup would anchor the region’s transition from fuel-centric refining toward chemicals at a time when several Korean producers are weighing shutdowns of older naphtha crackers. For the industry as a whole, Shaheen is becoming a test case for the thesis S-Oil laid out in its announcement: that Korea can hold its position in petrochemicals — a sector that grew into a pillar of chemical manufacturing in the decades after the Second World War — not by protecting legacy capacity but by replacing it with plants built for the current cost environment.

The company has staked its guidance on next year. Between now and then, the variables to watch are the ones S-Oil did not address: how quickly the new capacity finds buyers in an oversupplied regional market, and whether the cost advantage of integration proves as decisive in operation as it does on paper.